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Impact of Age and Comorbidity on Colorectal Cancer Screening Among Older Veterans FREE

Louise C. Walter, MD; Karla Lindquist, MS; Sean Nugent, BA; Tammy Schult, MS; Sei J. Lee, MD, MAS; Michele A. Casadei, BS; and Melissa R. Partin, PhD
[+] Article and Author Information

From the San Francisco Veterans Affairs Medical Center and the University of California, San Francisco, California, and the Minneapolis Veterans Affairs Medical Center, Minneapolis, Minnesota.


Disclaimer: The views expressed in this article are those of the authors and do not necessarily reflect the position or policy of the Department of Veterans Affairs.

Grant Support: Dr. Walter is supported by VA Health Services Research and Development grant IIR-04-427 and is a Robert Wood Johnson Physician Faculty Scholar. Dr. Lee is a Hartford Geriatrics Health Outcomes Research Scholar.

Potential Financial Conflicts of Interest: None disclosed.

Reproducible Research Statement:Study protocol and statistical code: Available from Dr. Walter (louise.walter@ucsf.edu). Data set: Not available.

Requests for Single Reprints: Louise C. Walter, MD, Veterans Affairs Medical Center 181G, 4150 Clement Street, San Francisco, CA 94121; e-mail, louise.walter@ucsf.edu.

Current Author Addresses: Drs. Walter and Lee, Ms. Lindquist, and Ms. Casadei: Veterans Affairs Medical Center 181G, 4150 Clement Street, San Francisco, CA 94121.

Mr. Nugent, Ms. Schult, and Dr. Partin: Minneapolis Veterans Affairs Medical Center, 1 Veterans Drive (152/2E), Minneapolis MN 55417.

Author Contributions: Conception and design: L.C. Walter.

Analysis and interpretation of the data: L.C. Walter, K. Lindquist, S. Nugent, S.J. Lee, M.R. Partin.

Drafting of the article: L.C. Walter, M.R. Partin.

Critical revision of the article for important intellectual content: L.C. Walter, K. Lindquist, S.J. Lee, M.R. Partin.

Final approval of the article: L.C. Walter, S.J. Lee, M.R. Partin.

Provision of study materials or patients: M.R. Partin.

Statistical expertise: K. Lindquist.

Obtaining of funding: L.C. Walter.

Administrative, technical, or logistic support: M.A. Casadei.

Collection and assembly of data: L.C. Walter, S. Nugent, T. Schult, M.R. Partin.


Ann Intern Med. 2009;150(7):465-473. doi:10.7326/0003-4819-150-7-200904070-00006
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Background: The Veterans Health Administration, the American Cancer Society, and the American Geriatrics Society recommend colorectal cancer screening for older adults unless they are unlikely to live 5 years or have significant comorbidity that would preclude treatment.

Objective: To determine whether colorectal cancer screening is targeted to healthy older patients and is avoided in older patients with severe comorbidity who have life expectancies of 5 years or less.

Design: Cohort study.

Setting: Veterans Affairs (VA) medical centers in Minneapolis, Minnesota; Durham, North Carolina; Portland, Oregon; and West Los Angeles, California, with linked national VA and Medicare administrative claims.

Patients: 27 068 patients 70 years or older who had an outpatient visit at 1 of 4 VA medical centers in 2001 or 2002 and were due for screening.

Measurements: The main outcome was receipt of fecal occult blood testing (FOBT), colonoscopy, sigmoidoscopy, or barium enema in 2001 or 2002, on the basis of national VA and Medicare claims. Charlson–Deyo comorbidity scores at the start of 2001 were used to stratify patients into 3 groups ranging from no comorbidity (score of 0) to severe comorbidity (score ≥4), and 5-year mortality was determined for each group.

Results: 46% of patients were screened from 2001 through 2002. Only 47% of patients with no comorbidity were screened despite having life expectancies greater than 5 years (5-year mortality, 19%). Although the incidence of screening decreased with age and worsening comorbidity, it was still 41% for patients with severe comorbidity who had life expectancies less than 5 years (5-year mortality, 55%). The number of VA outpatient visits predicted screening independent of comorbidity, such that patients with severe comorbidity and 4 or more visits had screening rates similar to or higher than those of healthier patients with fewer visits.

Limitations: Some tests may have been performed for nonscreening reasons. The generalizability of findings to persons who do not use the VA system is uncertain.

Conclusion: Advancing age was inversely associated with colorectal cancer screening, whereas comorbidity was a weaker predictor. More attention to comorbidity is needed to better target screening to older patients with substantial life expectancies and avoid screening older patients with limited life expectancies.

Primary Funding Source: VA Health Services Research and Development.

Editors' Notes
Context

  • Guidelines increasingly state that screening for cancer should be targeted to people who will live long enough to benefit from it.

Content

  • The investigators studied receipt of colorectal cancer screening in 27 068 screen-eligible VA patients 70 years or older. Only 47% of patients with no comorbidity (5-year mortality rate, 19%) were screened, whereas 41% with severe comorbidity (5-year mortality rate, 55%) were screened. Rates were somewhat lower for older men but varied only slightly by life expectancy.

Caution

  • Some tests may have been done for diagnosis rather than screening.

Implication

  • In this population of elderly men, screening did not target healthier patients.

—The Editors

Colorectal cancer screening guidelines recommend screening older adults who have substantial life expectancies according to age and comorbid conditions (1). For example, the U.S. Preventive Services Task Force recommends routine screening until age 75 years, whereas the Veterans Health Administration, the American Cancer Society, and the American Geriatrics Society (25) recommend colorectal cancer screening for older adults unless they are unlikely to live 5 years or have significant comorbid conditions that would preclude treatment. Targeting screening to healthy persons who are likely to live at least 5 years is recommended because randomized trials of fecal occult blood testing (FOBT) suggest that a difference in colorectal cancer mortality between screened and unscreened persons does not become noticeable until at least 5 years after screening (68). Therefore, persons with a life expectancy of 5 years or less are not likely to benefit from screening but remain at risk for harms that may occur immediately, such as complications from procedures and the treatment of clinically unimportant disease (910). However, it remains unclear whether screening is being targeted to healthy older persons with substantial life expectancies and avoided in older persons with significant comorbidity, for whom the risks of screening outweigh the benefits.

Previous studies of associations among age, comorbidity, and receipt of cancer screening have found that age is a stronger determinant of screening than comorbidity. For example, whereas advancing age is consistently associated with lower screening rates, worsening comorbidity has had little effect on the use of screening mammography, Papanicolaou smears, or prostate-specific antigen screening (1113). Previous studies of the relationship between colorectal cancer screening and comorbidity have been limited by small sample size, short follow-up times, and focus on FOBT rather than all types of colorectal cancer screening tests (1415). In addition, previous Veterans Affairs (VA) studies have not measured colorectal cancer screening performed outside the VA health care system by means of Medicare (1517). Having a better understanding of how comorbidity and age affect overall screening use is particularly important for colorectal cancer screening because the tests and follow-up procedures are often more invasive than those for other types of cancer and may result in substantial harms, such as major bleeding events, colon perforation, or stroke—especially in elderly persons with limited life expectancies (9, 1819).

To characterize the use of colorectal cancer screening across a prognostic spectrum of advancing age and comorbidity, we examined VA data and Medicare claims for patients 70 years of age or older who were seen at 4 geographically diverse VA facilities. Specifically, we determined 2-year screening incidence and 5-year mortality rate for subgroups of older patients without significant comorbidity for whom guidelines recommend screening, as well as for subgroups of older patients with severe comorbidity for whom most guidelines agree that the risks of screening outweigh the benefits.

Data Sources and Patients

We identified a cohort of screen-eligible patients on 1 January 2001 and followed them for 2 years for the performance of colorectal cancer screening. We obtained data for this cohort study from National VA Data Systems, clinical data extracted from the electronic record system (Veterans Health Information Systems and Technology Architectures) of 4 VA medical centers (Minneapolis, Minnesota; Durham, North Carolina; Portland, Oregon; and West Los Angeles, California), and Medicare claims. National VA data included the National Patient Care Database (which captures all inpatient and outpatient claims within the VA), Fee Basis Files (which capture claims for non-VA services paid for by the VA), and the Vital Status File (which captures mortality data for veterans) (20). Clinical data extracted from the 4 VA centers included text entered by clinicians in response to computerized clinical reminders about colorectal cancer screening (21). We used linked Medicare claims from the VA Information Resource Center to capture services provided to our cohort outside the VA by Medicare (22).

On the basis of these data sources, we identified a cohort of 60 933 patients 70 years of age or older who had at least 1 outpatient visit within the VA health care system or Medicare between 1 January 2000 and 31 December 2000 (the period during which we measured comorbidity) and at least 1 outpatient visit at 1 of the 4 VA centers between 1 January 2001 and 31 December 2002 (the period during which we measured the performance of colorectal cancer screening) (Figure 1). We selected the 4 VA centers for geographic diversity. We excluded 11 817 (19%) patients who were enrolled in Medicare managed care at any point from 1 January 2000 to 31 December 2002, because they lacked Medicare claims. In addition, patients had to be eligible for screening to be included in our cohort. Therefore, we used VA and Medicare inpatient and outpatient claims from the 8-year period before the start of 2001 (dating back to 1 October 1992 for VA claims and 1 January 1999 for Medicare claims) to exclude 11 200 (18%) patients with a history of colorectal cancer, colitis, colorectal polyps, colectomy, or colostomy and 8153 (13%) patients who had any history of a colonoscopy or had had a sigmoidoscopy or barium enema within 5 years and were therefore not due for screening at the start of 2001. We also used claims from the 6 months before their index test to exclude 2695 (4%) of patients who had signs or symptoms that would justify the performance of a test for nonscreening purposes (Figure 1). This left a final screen-eligible cohort of 27 068 patients on 1 January 2001.

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Figure 1.
Study flow diagram.

Eligibility criteria included having been seen in an outpatient clinic at 1 of 4 Veterans Affairs (VA) centers between 1 January 2001 and 31 December 2002, which indicated that the VA was at least partially responsible for medical care, but data on colorectal cancer screening were gathered during the entire 2-year screening interval from both national VA and Medicare claims. Additional eligibility criteria included having at least 1 outpatient visit between 1 January and 31 December 2000 to define comorbidity as of 1 January 2001.

* Defined by searching VA and Medicare inpatient and outpatient claims before 1 January 2001, dating as far back as 1 October 1992 for VA claims and 1 January 1999 for Medicare claims.

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Data Collection and Measurement
Outcome Variables

We assessed receipt of colorectal cancer screening between 1 January 2001 and 31 December 2002 for our cohort across the VA health care system and Medicare, because many elderly veterans use more than 1 VA center and most are enrolled in Medicare (23). We identified colorectal cancer screening in National VA Data Systems and linked Medicare payment data (hospital outpatient and physician/supplier files) by using International Classification of Disease, Ninth Revision (ICD-9), codes; Current Procedural Terminology (CPT) codes; and Level II Healthcare Common Procedure Coding System (HCPCS) codes for FOBT (CPT codes 82270, 82273, and 82274 and HCPCS code G0107), colonoscopy (ICD-9 codes 45.22, 45.23, 45.25, 45.41, 45.42, and 45.43; CPT codes 44388 to 44394, 45355, and 45378 to 45385; and HCPCS codes G0105, G0121), sigmoidoscopy (ICD-9 codes 45.24, 48.22 to 48.24, 48.26, 48.35, and 48.36; CPT codes 45300, 45303, 45305, 45308, 45309, 45315, 45320, 45330 to 45334, and 45337 to 45339; and HCPCS code G0104), or barium enema (ICD-9 code 87.64; CPT codes 74270 and 74280; and HCPCS codes G0106, G0120, and G0122) (2427). We assigned patients to 1 of the 4 screening procedures on the basis of their first test during 2001 through 2002. We chose a 2-year screening period to allow sufficient time for screening tests to be scheduled and performed; this is also the screening interval used in randomized trials of FOBT (67).

We obtained vital status through 31 December 2005 from the VA Vital Status File to determine 5-year mortality rates. The VA Vital Status File is similar to the National Death Index in terms of accuracy and completeness (28). We used 5-year mortality rates descriptively to identify conditions associated with having a life expectancy less than 5 years (5-year mortality rate >50%).

Predictor Variables

We assigned patients to 1 of 3 categories on the basis of their age on 1 January 2001: 70 to 74 years, 75 to 79 years, or 80 years or older. We defined the burden of comorbidity by using the Deyo adaptation of the Charlson Comorbidity Index (2931), a summary measure of 19 chronic disease diagnoses from administrative data that are selected and weighted according to their association with mortality. We calculated Charlson–Deyo scores from VA and Medicare inpatient and outpatient claims during the 12 months before the start of 2001 (3234). We categorized patients as having no significant comorbidity if they had a Charlson–Deyo score of 0, average comorbidity if they had a Charlson–Deyo score of 1 to 3, and severe comorbidity if they had a Charlson–Deyo score of 4 or greater. We chose these cutoffs a priori to assess how extremes in comorbidity influence screening; they have been used in previous studies (13, 31). Another measure of illness included being homebound, defined as enrollment in VA Home-Based Primary Care at the start of 2001. We also measured whether a clinician responded to VA clinical reminders that colorectal cancer screening was refused or contraindicated in 2001 or 2002 (35).

We also ascertained other factors known to influence the use of cancer screening from VA and Medicare administrative data and linkage to the 2000 U.S. Census (Table 1) (36). We based the number of outpatient visits during the 2-year screening interval on primary care, gastroenterology, or general surgery clinic codes from national VA data. We included general medicine, cardiology, endocrinology, diabetes, hypertension, pulmonary, and women's clinics as primary care clinics because they are defined as such by the VA colorectal cancer screening quality indicator (37). The Committee on Human Research at the University of California, San Francisco; the Committee for Research and Development at the San Francisco VA Medical Center; and the institutional review board at the Minneapolis VA Medical Center approved the study.

Table Jump PlaceholderTable 1.  Baseline Characteristics
Statistical Analysis

For all estimates of colorectal cancer screening incidence, we observed patients from baseline (1 January 2001) until their first screening test or death or the end of the screening period (31 December 2002). We did not censor patients for reasons other than death or the end of the screening period; we had no reason to assume that screening would not be recorded otherwise, because we had access to both VA and Medicare claims for all patients up until these times. We first used Kaplan–Meier analysis to estimate the unadjusted 2-year cumulative incidence and 95% CIs of colorectal cancer screening according to baseline characteristics. Next, we used Cox regression models to estimate 2-year cumulative incidence of colorectal cancer screening with bootstrapped 95% CIs that adjusted for age, sex, race, marital status, VA site, education, income, Charlson–Deyo comorbidity category, and an age–site interaction. We chose not to adjust for number of visits or homebound status because these were probably in the causal pathway for how age and comorbidity affect screening. In addition, to describe the association of age and comorbidity combined, we categorized patients into 9 subgroups on the basis of age (3 categories) and Charlson–Deyo score (3 categories) and plotted the Kaplan–Meier estimates of 5-year mortality versus screening incidence for each of the 9 subgroups. We used log rank and trend tests where appropriate when comparing Kaplan–Meier rates across categories. We used SAS, version 9.1 (SAS Institute, Cary, North Carolina), and Stata/SE, version 10.0 (StataCorp, College Station, Texas), for all analyses.

Role of the Funding Source

Dr. Walter is supported by a VA Health Services Research and Development grant. The funding source had no role in the design, conduct, or analysis of this study or in the decision to submit the manuscript for publication.

Patient Characteristics

Table 1 shows the baseline characteristics of the 27 068 patients. Consistent with the elderly veteran population, 96% were men and 87% were white. The median age was 77 years (interquartile range, 73 to 80 years). The median Charlson–Deyo score was 1.0 (interquartile range, 0 to 2), with scores ranging from 0 to 16. Thirty-six percent of patients had a Charlson–Deyo score of 0, and 12% of patients had a Charlson–Deyo score of 4 or greater. Only 261 (1%) patients in our cohort would have been defined as inappropriate for screening by the VA colorectal cancer screening quality indicator, which excludes patients who have cancer of the liver, pancreas, or esophagus or are eligible for hospice (37). On the basis of responses to clinical reminders, only 599 (2%) patients had documentation that screening was refused or contraindicated.

Of the 27 068 patients, 8518 (31%) died within 5 years (19% of patients with no comorbidity and 55% of patients with severe comorbidity). Combining age and Charlson–Deyo score resulted in 5-year mortality rates that ranged from 13% (495 of 3846) for patients age 70 to 74 years without comorbidity to 66% (585 of 893) for patients 80 years or older with severe comorbidity (Figure 2). Patients who had congestive heart failure, dementia, chronic renal failure, or metastatic cancer or were homebound had 5-year mortality rates greater than 50%.

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Figure 2.
Colorectal cancer screening incidence versus 5-year mortality for different age groups as comorbidity increases (n = 27 068).

Within each age group, screening incidence decreased only a small amount as comorbidity worsened. The lines illustrate the relatively flat incidence of screening among patients with no comorbidity, average comorbidity, and severe comorbidity for each age group. If screening was targeted to older patients with substantial life expectancies and away from those with severe comorbidity, all lines would start much higher and slope down more steeply.

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Colorectal Cancer Screening Rates

Of the 27 068 patients, 12 354 (46%) received colorectal cancer screening in 2001 or 2002; 8288 (31%) were screened in the first year. Of those screened, 8346 (68%) had their index screening test during the 2-year period in the VA health care system (5585 [45%] at 1 of the 4 VA centers studied and 2761 [22%] at another VA center), whereas 4008 (32%) had their tests within Medicare. Among the 12 354 patients who were screened, 77% had FOBT as their index screening test, 13% had colonoscopy, 8% had sigmoidoscopy, and 2% had barium enema; 5.4% had both FOBT and sigmoidoscopy.

Advancing age was associated with decreased colorectal cancer screening, whereas worsening comorbidity was a weaker predictor (Table 2). For example, even for elderly patients with severe comorbid conditions, the incidence of screening did not fall below 30%, except among the few patients who were homebound or had dementia. On the other hand, screening incidence was only approximately 50% even among patients with characteristics predictive of living more than 5 years, such as age 70 to 74 years or a Charlson–Deyo score of 0. When we combined age and Charlson–Deyo score, screening incidence ranged from 51% among patients age 70 to 74 years without comorbidity to 34% among patients 80 years or older with severe comorbidity (P < 0.001). Figure 2 shows that screening incidence within each age group varied little with worsening comorbidity, even over a wide range of 5-year mortality rates. For example, screening incidence among persons 80 years or older was similar for those with no comorbidity (5-year mortality rate, 31%) and severe comorbidity (5-year mortality rate, 66%) at 38% and 34%, respectively (P = 0.058). In multivariate analyses, the association of age and comorbidity with colorectal cancer screening incidence remained similar after we adjusted for sex, race, marital status, VA site, education, income, and age–site interaction (P < 0.001), which indicates that the incidence of screening at the Los Angeles site did not differ as much across age groups as it did at the other sites (Table 2).

Table Jump PlaceholderTable 2.  Two-Year Cumulative Colorectal Cancer Screening Incidence Among Persons 70 Years or Older, by Patient Characteristic

The number of VA outpatient visits to primary care, gastroenterology, or general surgery clinics during the study was one of the strongest predictors of screening in unadjusted and adjusted analyses (Table 2). Overall, 22 253 (82%) patients were seen at least once at a VA primary care, gastroenterology, or general surgery clinic from 2001 through 2002. Colorectal cancer screening incidence increased with increasing visits, ranging from 23% for patients with no visits to 58% for patients with 4 or more visits (P for trend < 0.001). However, persons with severe comorbidity had more visits than those without comorbidity. For example, 984 of 3244 (30%) patients with severe comorbidity had 4 or more visits, whereas only 1305 of 9658 (13%) patients without comorbidity had 4 or more visits. Because the number of visits predicted screening independent of comorbidity, screening incidence increased with number of visits even among patients with severe comorbidity (Figure 3). As a result, patients with severe comorbidity and 4 or more visits had a screening incidence of 50%, which was similar or higher than the screening incidence for healthier patients with fewer visits.

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Figure 3.
Patients 70 years or older who had colorectal cancer screening in 2001 or 2002, by comorbidity and number of Veterans Affairs outpatient visits (n = 27 068).

Number of visits was defined by the number of visits between 1 January 2001 and 31 December 2002 to Veterans Affairs primary care, gastroenterology, or general surgery clinics (clinic codes 301, 303, 305, 306, 307, 309, 312, 321 to 323, and 401).

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Fewer than half of veterans 70 years or older received colorectal cancer screening during the 2-year period from 2001 through 2002. Advancing age was strongly and inversely associated with screening, whereas comorbidity was a weaker predictor. As a result, many healthy older patients with substantial life expectancies are not being screened, whereas some patients with severe comorbidity are being screened. For example, only 47% of patients 70 years or older without comorbidity were screened, despite having a high probability of living longer than 5 years (5-year survival rate, 81%). In addition, the number of VA outpatient visits was a strong predictor of screening independent of comorbidity, such that patients without comorbidity who did not attend a primary care, gastroenterology, or general surgery clinic had a lower incidence of screening than patients with severe comorbidity who attended these clinics.

Previous studies of the associations among age, comorbidity, and receipt of cancer screening have found similar problems with the targeting of cancer screening tests to healthy older patients. We identified English-language literature related to cancer screening, age, and comorbidity published between January 1998 and December 2008 by using MEDLINE. Our search terms included cancer screening, aged, and comorbidity or health status. Whereas cancer screening generally decreases with advancing age, increasing comorbidity has been shown to have little effect on the relatively high rates of mammography, Papanicolaou smears, and prostate-specific antigen screening (1113). In contrast, colorectal cancer screening rates have been found to be generally low across the United States, especially among older adults, and the effect of comorbidity on screening is not well described (3841). The incidence of colorectal cancer screening that we report is based on the actual performance of screening and is lower than that reported in national surveys, which frequently overestimate screening because of patients' desire to report behavior in a favorable light (4243). Our screening rates are consistent with those of previous claims-based studies (16, 40, 44). For example, we found that 31% of veterans 70 years or older were screened in 2001, whereas a study of veterans age 49 to 75 years found that annual screening incidence ranged from 19% to 31% between 1998 and 2004 (16). An advantage of our study over previous studies that used national VA databases is that we were able to identify patients who had screening outside the VA that was paid for by Medicare, which accounted for 32% of veterans screened. On the basis of this comprehensive view of colorectal cancer screening in elderly veterans, we found that—as with other cancer screening tests—age was a stronger predictor of colorectal cancer screening than comorbidity.

Our finding that colorectal cancer screening is not optimally targeted to healthy older patients, or is avoided in older patients with severe comorbidity, may be explained in several possible ways. First, consistent with other studies, we found that more frequent medical visits are associated with increased cancer screening independent of a patient's comorbidity (45). This may contribute to underscreening of healthy older patients, who see doctors less frequently, and to overscreening of patients with severe comorbidity. Second, clinicians may have difficulty estimating life expectancy because all available methods for predicting an individual's life expectancy are imperfect. However, even among patients age 70 to 74 years without comorbidity, whom few clinicians would expect to die in 10 years (9), the 2-year cumulative incidence of screening was still only 51%. This may in part be driven by the belief that colorectal cancer screening is more unpleasant and invasive than other cancer screening tests (4647). For example, annual rates of prostate-specific antigen screening, which entails a blood test, are more than double the rates of colorectal cancer screening among male veterans age 70 to 74 years without comorbidity (13). Third, healthy older patients visit clinicians less often and may be less willing to accept recommendations for screening. However, we found that fewer than 2% of patients in our cohort had documentation that screening was refused. Finally, quality indicators, which are used extensively by the VA, promote colorectal cancer screening regardless of comorbidity, which may contribute to the overscreening of patients with severe comorbidity (35, 48). For example, the VA's 2001 to 2002 colorectal cancer screening quality indicator would have encouraged screening all patients in our cohort who were seen in primary care clinics, except for the 1% of patients who had cancer of the esophagus, liver, or pancreas or were eligible for hospice (37). Because almost one third of our cohort died within 5 years, this quality indicator would have encouraged screening in many patients who were unlikely to benefit given their short survival. An upper age limit of 80 years was instituted in fiscal year 2005, which appropriately excludes more patients with limited life expectancies (9, 15). However, it does not encourage clinicians to better target colorectal cancer screening to healthy older patients. A better quality indicator would encourage high screening rates in older patients without comorbidity and low rates in older patients with severe comorbidity (35).

In addition, the colorectal cancer screening guidelines published by the U.S. Preventive Services Task Force in 2008 (49) recommend continuing screening only until age 75 years, on the basis of a decision model that used chronologic age rather than comorbidity-adjusted life expectancy. The strong relationship between comorbidity and life expectancy and our finding that the use of colorectal cancer screening varied little across dramatically different levels of comorbidity suggest that refinements to the guidelines are needed to explicitly encourage or discourage screening on the basis of the severity of comorbidity, rather than solely on the basis of the age of the patient. Similarly, optimizing the targeting of colorectal cancer screening will probably require changes in how preventive care is delivered. The current strategy relies on finding opportunities for screening when patients visit clinicians for a medical illness (5051), which targets screening to patients with worse comorbidity and misses healthy patients.

Our study has several limitations. First, claims data do not indicate the reasons a test was ordered or the purpose of medical visits, which means that some tests may have been performed for nonscreening reasons. However, we used claims data to exclude patients who had received diagnoses or had symptoms that would justify performing a test for a nonscreening purpose (Figure 1) (16). In addition, FOBT is the predominant mode of screening in the VA, and previous studies have found that only 3% of FOBTs ordered by VA clinicians were for nonscreening reasons (52). Second, although our data sources completely capture screening within the VA health care system, we may have missed some tests performed outside the VA. For example, Medicare claims do not capture tests paid for by other sources. Third, although the Deyo adaptation of the Charlson Comorbidity Index is strongly predictive of 5-year mortality, it does not include all factors that may determine life expectancy, such as functional status (31). However, an advantage of our study is that we calculated actual 5-year mortality rates, which confirmed that patients without comorbidity had a life expectancy greater than 5 years and those with severe comorbidity had a life expectancy of less than 5 years. Finally, our cohort primarily comprised men who use the VA, so the generalizability of our findings to persons who do not use the VA is uncertain. However, understanding screening within the VA is important in its own right, because the VA is the largest health care system in the United States and a leader in improving health care quality (53).

In conclusion, colorectal cancer screening could be better targeted among older patients by considering comorbidity in addition to age. Cancer screening guidelines should be more explicit about which combinations of age and comorbidity identify older patients who have substantial life expectancies and those who are likely to die within 5 years (54). Clinicians could then consider such characteristics in concert with clinical judgment to estimate an older individual's potential risks and benefits from screening, and use shared decision making to help older patients arrive at an informed screening decision.

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Gatto NM, Frucht H, Sundararajan V, Jacobson JS, Grann VR, Neugut AI.  Risk of perforation after colonoscopy and sigmoidoscopy: a population-based study. J Natl Cancer Inst. 2003; 95:230-6. PubMed
 
VA Information Resource Center data sources by name. Hines, IL: VA Information Resource Center; 2008. Accessed athttp://www.virec.research.va.gov/DataSourcesName/DataNames.htmon 8 January 2009.
 
Perlin JB, Kolodner RM, Roswell RH.  The Veterans Health Administration: quality, value, accountability, and information as transforming strategies for patient-centered care. Am J Manag Care. 2004; 10:828-36. PubMed
 
VA Information Resource Center.  Research findings from the VA Medicare data merge initiative, report to the under secretary for health, September 2003. Hines, IL: VA Information Resource Center; 2003. Accessed athttp://www.virec.research.va.gov/DataSourcesName/VA-MedicareData/USHreport.pdfon 8 January 2009.
 
Shen Y, Hendricks A, Zhang S, Kazis LE.  VHA enrollees' health care coverage and use of care. Med Care Res Rev. 2003; 60:253-67. PubMed
 
Pham HH, Schrag D, Hargraves JL, Bach PB.  Delivery of preventive services to older adults by primary care physicians. JAMA. 2005; 294:473-81. PubMed
 
Cooper GS, Chak A, Koroukian S.  The polyp detection rate of colonoscopy: a national study of Medicare beneficiaries. Am J Med. 2005; 118:1413. PubMed
 
Freeman JL, Klabunde CN, Schussler N, Warren JL, Virnig BA, Cooper GS.  Measuring breast, colorectal, and prostate cancer screening with medicare claims data. Med Care. 2002; 40:IV-36-42. PubMed
 
Beebe M, Dalton JA, Duffy C, Evans D, Glenn RL, Hayden D. et al.  Current Procedural Terminology 2003. Chicago: American Med Assoc; 2002.
 
Sohn MW, Arnold N, Maynard C, Hynes DM.  Accuracy and completeness of mortality data in the Department of Veterans Affairs. Popul Health Metr. 2006; 4:2. PubMed
 
Deyo RA, Cherkin DC, Ciol MA.  Adapting a clinical comorbidity index for use with ICD-9-CM administrative databases. J Clin Epidemiol. 1992; 45:613-9. PubMed
 
SEER-Medicare Program.  SAS macro for Charlson Comorbidity Index. Bethesda, MD: National Cancer Institute; 2007. Accessed athealthservices.cancer.gov/seermedicare/program/charlson.comorbidity.macro.txton 8 January 2009.
 
Charlson ME, Pompei P, Ales KL, MacKenzie CR.  A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987; 40:373-83. PubMed
 
Kashner TM.  Agreement between administrative files and written medical records: a case of the Department of Veterans Affairs. Med Care. 1998; 36:1324-36. PubMed
 
Szeto HC, Coleman RK, Gholami P, Hoffman BB, Goldstein MK.  Accuracy of computerized outpatient diagnoses in a Veterans Affairs general medicine clinic. Am J Manag Care. 2002; 8:37-43. PubMed
 
Klabunde CN, Legler JM, Warren JL, Baldwin LM, Schrag D.  A refined comorbidity measurement algorithm for claims-based studies of breast, prostate, colorectal, and lung cancer patients. Ann Epidemiol. 2007; 17:584-90. PubMed
 
Walter LC, Davidowitz NP, Heineken PA, Covinsky KE.  Pitfalls of converting practice guidelines into quality measures: lessons learned from a VA performance measure. JAMA. 2004; 291:2466-70. PubMed
 
U.S. Census Bureau.  Census 2000 summary file 3—United States. Washington, DC: U.S. Census Bureau; 2002. Accessed athttp://www2.census.gov/census_2000/datasets/Summary_File_3/0_National/on 8 January 2009.
 
VA Office of Quality and Performance.  FY2001 VHA Performance Measurement System Technical Manual. Washington, DC: Department of Veterans Affairs; 2001. Accessed athttp://www.oqp.med.va.gov/on 8 January 2009.
 
Sirovich BE, Schwartz LM, Woloshin S.  Screening men for prostate and colorectal cancer in the United States: does practice reflect the evidence? JAMA. 2003; 289:1414-20. PubMed
 
Chen X, White MC, Peipins LA, Seeff LC.  Increase in screening for colorectal cancer in older Americans: results from a national survey. J Am Geriatr Soc. 2008; 56:1511-6. PubMed
 
Ananthakrishnan AN, Schellhase KG, Sparapani RA, Laud PW, Neuner JM.  Disparities in colon cancer screening in the Medicare population. Arch Intern Med. 2007; 167:258-64. PubMed
 
Cooper GS, Doug Kou T.  Underuse of colorectal cancer screening in a cohort of Medicare beneficiaries. Cancer. 2008; 112:293-9. PubMed
 
Jones RM, Mongin SJ, Lazovich D, Church TR, Yeazel MW.  Validity of four self-reported colorectal cancer screening modalities in a general population: differences over time and by intervention assignment. Cancer Epidemiol Biomarkers Prev. 2008; 17:777-84. PubMed
 
Partin MR, Grill J, Noorbaloochi S, Powell AA, Burgess DJ, Vernon SW. et al.  Validation of self-reported colorectal cancer screening behavior from a mixed-mode survey of veterans. Cancer Epidemiol Biomarkers Prev. 2008; 17:768-76. PubMed
 
Cooper GS, Koroukian SM.  Geographic variation among Medicare beneficiaries in the use of colorectal carcinoma screening procedures. Am J Gastroenterol. 2004; 99:1544-50. PubMed
 
Fenton JJ, Cai Y, Weiss NS, Elmore JG, Pardee RE, Reid RJ. et al.  Delivery of cancer screening: how important is the preventive health examination? Arch Intern Med. 2007; 167:580-5. PubMed
 
Ling BS, Moskowitz MA, Wachs D, Pearson B, Schroy PC.  Attitudes toward colorectal cancer screening tests. J Gen Intern Med. 2001; 16:822-30. PubMed
 
Walsh JM, Terdiman JP.  Colorectal cancer screening: clinical applications. JAMA. 2003; 289:1297-302. PubMed
 
Fisher DA, Judd L, Sanford NS.  Inappropriate colorectal cancer screening: findings and implications. Am J Gastroenterol. 2005; 100:2526-30. PubMed
 
Zauber AG, Lansdorp-Vogelaar I, Knudsen AB, Wilschut J, van Ballegooijen M, Kuntz KM.  Evaluating test strategies for colorectal cancer screening: a decision analysis for the U.S. Preventive Services Task Force. Ann Intern Med. 2008; 149:659-69. PubMed
 
Smith RA, Cokkinides V, Eyre HJ.  Cancer screening in the United States, 2007: a review of current guidelines, practices, and prospects. CA Cancer J Clin. 2007; 57:90-104. PubMed
 
Boulware LE, Marinopoulos S, Phillips KA, Hwang CW, Maynor K, Merenstein D. et al.  Systematic review: the value of the periodic health evaluation. Ann Intern Med. 2007; 146:289-300. PubMed
 
Fisher DA, Jeffreys A, Coffman CJ, Fasanella K.  Barriers to full colon evaluation for a positive fecal occult blood test. Cancer Epidemiol Biomarkers Prev. 2006; 15:1232-5. PubMed
 
Jha AK, Perlin JB, Kizer KW, Dudley RA.  Effect of the transformation of the Veterans Affairs Health Care System on the quality of care. N Engl J Med. 2003; 348:2218-27. PubMed
 
Gross CP, McAvay GJ, Krumholz HM, Paltiel AD, Bhasin D, Tinetti ME.  The effect of age and chronic illness on life expectancy after a diagnosis of colorectal cancer: implications for screening. Ann Intern Med. 2006; 145:646-53. PubMed
 

Figures

Grahic Jump Location
Figure 1.
Study flow diagram.

Eligibility criteria included having been seen in an outpatient clinic at 1 of 4 Veterans Affairs (VA) centers between 1 January 2001 and 31 December 2002, which indicated that the VA was at least partially responsible for medical care, but data on colorectal cancer screening were gathered during the entire 2-year screening interval from both national VA and Medicare claims. Additional eligibility criteria included having at least 1 outpatient visit between 1 January and 31 December 2000 to define comorbidity as of 1 January 2001.

* Defined by searching VA and Medicare inpatient and outpatient claims before 1 January 2001, dating as far back as 1 October 1992 for VA claims and 1 January 1999 for Medicare claims.

Grahic Jump Location
Grahic Jump Location
Figure 2.
Colorectal cancer screening incidence versus 5-year mortality for different age groups as comorbidity increases (n = 27 068).

Within each age group, screening incidence decreased only a small amount as comorbidity worsened. The lines illustrate the relatively flat incidence of screening among patients with no comorbidity, average comorbidity, and severe comorbidity for each age group. If screening was targeted to older patients with substantial life expectancies and away from those with severe comorbidity, all lines would start much higher and slope down more steeply.

Grahic Jump Location
Grahic Jump Location
Figure 3.
Patients 70 years or older who had colorectal cancer screening in 2001 or 2002, by comorbidity and number of Veterans Affairs outpatient visits (n = 27 068).

Number of visits was defined by the number of visits between 1 January 2001 and 31 December 2002 to Veterans Affairs primary care, gastroenterology, or general surgery clinics (clinic codes 301, 303, 305, 306, 307, 309, 312, 321 to 323, and 401).

Grahic Jump Location

Tables

Table Jump PlaceholderTable 1.  Baseline Characteristics
Table Jump PlaceholderTable 2.  Two-Year Cumulative Colorectal Cancer Screening Incidence Among Persons 70 Years or Older, by Patient Characteristic

References

Walter LC, Lewis CL, Barton MB.  Screening for colorectal, breast, and cervical cancer in the elderly: a review of the evidence. Am J Med. 2005; 118:1078-86. PubMed
CrossRef
 
U.S. Preventive Services Task Force.  Screening for colorectal cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2008; 149:627-37. PubMed
 
Kussman MJ.  VHA Directive 2007-004: Colorectal cancer screening. Washington, DC: Department of Veterans Affairs; 2007. Accessed athttp://www1.va.gov/vhapublications/ViewPublication.asp?pub_ID=1530on 8 January 2009.
 
Smith RA, von Eschenbach AC, Wender R, Levin B, Byers T, Rothenberger D, et al; ACS Prostate Cancer Advisory Committee, ACS Colorectal Cancer Advisory Committee, ACS Endometrial Cancer Advisory Committee.  American Cancer Society guidelines for the early detection of cancer: update of early detection guidelines for prostate, colorectal, and endometrial cancers. Also: update 2001—testing for early lung cancer detection. CA Cancer J Clin. 2001;51:38-75; quiz 77-80. [PMID: 11577479]
 
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Kronborg O, Fenger C, Olsen J, Jørgensen OD, Søndergaard O.  Randomised study of screening for colorectal cancer with faecal-occult-blood test. Lancet. 1996; 348:1467-71. PubMed
 
Hardcastle JD, Chamberlain JO, Robinson MH, Moss SM, Amar SS, Balfour TW. et al.  Randomised controlled trial of faecal-occult-blood screening for colorectal cancer. Lancet. 1996; 348:1472-7. PubMed
 
Mandel JS, Bond JH, Church TR, Snover DC, Bradley GM, Schuman LM. et al.  Reducing mortality from colorectal cancer by screening for fecal occult blood. Minnesota Colon Cancer Control Study. N Engl J Med. 1993; 328:1365-71. PubMed
 
Walter LC, Covinsky KE.  Cancer screening in elderly patients: a framework for individualized decision making. JAMA. 2001; 285:2750-6. PubMed
 
Ko CW, Sonnenberg A.  Comparing risks and benefits of colorectal cancer screening in elderly patients. Gastroenterology. 2005; 129:1163-70. PubMed
 
Burack RC, Gurney JG, McDaniel AM.  Health status and mammography use among older women. J Gen Intern Med. 1998; 13:366-72. PubMed
 
Walter LC, Lindquist K, Covinsky KE.  Relationship between health status and use of screening mammography and Papanicolaou smears among women older than 70 years of age. Ann Intern Med. 2004; 140:681-8. PubMed
 
Walter LC, Bertenthal D, Lindquist K, Konety BR.  PSA screening among elderly men with limited life expectancies. JAMA. 2006; 296:2336-42. PubMed
 
Heflin MT, Oddone EZ, Pieper CF, Burchett BM, Cohen HJ.  The effect of comorbid illness on receipt of cancer screening by older people. J Am Geriatr Soc. 2002; 50:1651-8. PubMed
 
Fisher DA, Galanko J, Dudley TK, Shaheen NJ.  Impact of comorbidity on colorectal cancer screening in the veterans healthcare system. Clin Gastroenterol Hepatol. 2007; 5:991-6. PubMed
 
El-Serag HB, Petersen L, Hampel H, Richardson P, Cooper G.  The use of screening colonoscopy for patients cared for by the Department of Veterans Affairs. Arch Intern Med. 2006; 166:2202-8. PubMed
 
Etzioni DA, Yano EM, Rubenstein LV, Lee ML, Ko CY, Brook RH. et al.  Measuring the quality of colorectal cancer screening: the importance of follow-up. Dis Colon Rectum. 2006; 49:1002-10. PubMed
 
Whitlock EP, Lin JS, Liles E, Beil TL, Fu R.  Screening for colorectal cancer: a targeted, updated systematic review for the U.S. Preventive Services Task Force. Ann Intern Med. 2008; 149:638-58. PubMed
 
Gatto NM, Frucht H, Sundararajan V, Jacobson JS, Grann VR, Neugut AI.  Risk of perforation after colonoscopy and sigmoidoscopy: a population-based study. J Natl Cancer Inst. 2003; 95:230-6. PubMed
 
VA Information Resource Center data sources by name. Hines, IL: VA Information Resource Center; 2008. Accessed athttp://www.virec.research.va.gov/DataSourcesName/DataNames.htmon 8 January 2009.
 
Perlin JB, Kolodner RM, Roswell RH.  The Veterans Health Administration: quality, value, accountability, and information as transforming strategies for patient-centered care. Am J Manag Care. 2004; 10:828-36. PubMed
 
VA Information Resource Center.  Research findings from the VA Medicare data merge initiative, report to the under secretary for health, September 2003. Hines, IL: VA Information Resource Center; 2003. Accessed athttp://www.virec.research.va.gov/DataSourcesName/VA-MedicareData/USHreport.pdfon 8 January 2009.
 
Shen Y, Hendricks A, Zhang S, Kazis LE.  VHA enrollees' health care coverage and use of care. Med Care Res Rev. 2003; 60:253-67. PubMed
 
Pham HH, Schrag D, Hargraves JL, Bach PB.  Delivery of preventive services to older adults by primary care physicians. JAMA. 2005; 294:473-81. PubMed
 
Cooper GS, Chak A, Koroukian S.  The polyp detection rate of colonoscopy: a national study of Medicare beneficiaries. Am J Med. 2005; 118:1413. PubMed
 
Freeman JL, Klabunde CN, Schussler N, Warren JL, Virnig BA, Cooper GS.  Measuring breast, colorectal, and prostate cancer screening with medicare claims data. Med Care. 2002; 40:IV-36-42. PubMed
 
Beebe M, Dalton JA, Duffy C, Evans D, Glenn RL, Hayden D. et al.  Current Procedural Terminology 2003. Chicago: American Med Assoc; 2002.
 
Sohn MW, Arnold N, Maynard C, Hynes DM.  Accuracy and completeness of mortality data in the Department of Veterans Affairs. Popul Health Metr. 2006; 4:2. PubMed
 
Deyo RA, Cherkin DC, Ciol MA.  Adapting a clinical comorbidity index for use with ICD-9-CM administrative databases. J Clin Epidemiol. 1992; 45:613-9. PubMed
 
SEER-Medicare Program.  SAS macro for Charlson Comorbidity Index. Bethesda, MD: National Cancer Institute; 2007. Accessed athealthservices.cancer.gov/seermedicare/program/charlson.comorbidity.macro.txton 8 January 2009.
 
Charlson ME, Pompei P, Ales KL, MacKenzie CR.  A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987; 40:373-83. PubMed
 
Kashner TM.  Agreement between administrative files and written medical records: a case of the Department of Veterans Affairs. Med Care. 1998; 36:1324-36. PubMed
 
Szeto HC, Coleman RK, Gholami P, Hoffman BB, Goldstein MK.  Accuracy of computerized outpatient diagnoses in a Veterans Affairs general medicine clinic. Am J Manag Care. 2002; 8:37-43. PubMed
 
Klabunde CN, Legler JM, Warren JL, Baldwin LM, Schrag D.  A refined comorbidity measurement algorithm for claims-based studies of breast, prostate, colorectal, and lung cancer patients. Ann Epidemiol. 2007; 17:584-90. PubMed
 
Walter LC, Davidowitz NP, Heineken PA, Covinsky KE.  Pitfalls of converting practice guidelines into quality measures: lessons learned from a VA performance measure. JAMA. 2004; 291:2466-70. PubMed
 
U.S. Census Bureau.  Census 2000 summary file 3—United States. Washington, DC: U.S. Census Bureau; 2002. Accessed athttp://www2.census.gov/census_2000/datasets/Summary_File_3/0_National/on 8 January 2009.
 
VA Office of Quality and Performance.  FY2001 VHA Performance Measurement System Technical Manual. Washington, DC: Department of Veterans Affairs; 2001. Accessed athttp://www.oqp.med.va.gov/on 8 January 2009.
 
Sirovich BE, Schwartz LM, Woloshin S.  Screening men for prostate and colorectal cancer in the United States: does practice reflect the evidence? JAMA. 2003; 289:1414-20. PubMed
 
Chen X, White MC, Peipins LA, Seeff LC.  Increase in screening for colorectal cancer in older Americans: results from a national survey. J Am Geriatr Soc. 2008; 56:1511-6. PubMed
 
Ananthakrishnan AN, Schellhase KG, Sparapani RA, Laud PW, Neuner JM.  Disparities in colon cancer screening in the Medicare population. Arch Intern Med. 2007; 167:258-64. PubMed
 
Cooper GS, Doug Kou T.  Underuse of colorectal cancer screening in a cohort of Medicare beneficiaries. Cancer. 2008; 112:293-9. PubMed
 
Jones RM, Mongin SJ, Lazovich D, Church TR, Yeazel MW.  Validity of four self-reported colorectal cancer screening modalities in a general population: differences over time and by intervention assignment. Cancer Epidemiol Biomarkers Prev. 2008; 17:777-84. PubMed
 
Partin MR, Grill J, Noorbaloochi S, Powell AA, Burgess DJ, Vernon SW. et al.  Validation of self-reported colorectal cancer screening behavior from a mixed-mode survey of veterans. Cancer Epidemiol Biomarkers Prev. 2008; 17:768-76. PubMed
 
Cooper GS, Koroukian SM.  Geographic variation among Medicare beneficiaries in the use of colorectal carcinoma screening procedures. Am J Gastroenterol. 2004; 99:1544-50. PubMed
 
Fenton JJ, Cai Y, Weiss NS, Elmore JG, Pardee RE, Reid RJ. et al.  Delivery of cancer screening: how important is the preventive health examination? Arch Intern Med. 2007; 167:580-5. PubMed
 
Ling BS, Moskowitz MA, Wachs D, Pearson B, Schroy PC.  Attitudes toward colorectal cancer screening tests. J Gen Intern Med. 2001; 16:822-30. PubMed
 
Walsh JM, Terdiman JP.  Colorectal cancer screening: clinical applications. JAMA. 2003; 289:1297-302. PubMed
 
Fisher DA, Judd L, Sanford NS.  Inappropriate colorectal cancer screening: findings and implications. Am J Gastroenterol. 2005; 100:2526-30. PubMed
 
Zauber AG, Lansdorp-Vogelaar I, Knudsen AB, Wilschut J, van Ballegooijen M, Kuntz KM.  Evaluating test strategies for colorectal cancer screening: a decision analysis for the U.S. Preventive Services Task Force. Ann Intern Med. 2008; 149:659-69. PubMed
 
Smith RA, Cokkinides V, Eyre HJ.  Cancer screening in the United States, 2007: a review of current guidelines, practices, and prospects. CA Cancer J Clin. 2007; 57:90-104. PubMed
 
Boulware LE, Marinopoulos S, Phillips KA, Hwang CW, Maynor K, Merenstein D. et al.  Systematic review: the value of the periodic health evaluation. Ann Intern Med. 2007; 146:289-300. PubMed
 
Fisher DA, Jeffreys A, Coffman CJ, Fasanella K.  Barriers to full colon evaluation for a positive fecal occult blood test. Cancer Epidemiol Biomarkers Prev. 2006; 15:1232-5. PubMed
 
Jha AK, Perlin JB, Kizer KW, Dudley RA.  Effect of the transformation of the Veterans Affairs Health Care System on the quality of care. N Engl J Med. 2003; 348:2218-27. PubMed
 
Gross CP, McAvay GJ, Krumholz HM, Paltiel AD, Bhasin D, Tinetti ME.  The effect of age and chronic illness on life expectancy after a diagnosis of colorectal cancer: implications for screening. Ann Intern Med. 2006; 145:646-53. PubMed
 

Letters

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

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Hemoglobin values and age are significant predictors of positive faecal occult blood test.
Posted on April 14, 2009
Giuseppe Lippi
Sezione di Chimica Clinica e Microscopia Clinica
Conflict of Interest: None Declared

TO THE EDITOR:

Population based mass screening for colorectal cancer (CRC) has been a matter of debate for decades (1). We read with interest the article of Walter et al, who concluded that advancing age was inversely associated with colorectal cancer screening, whereas comorbidity was a weaker predictor, so that more attention to comorbidity is needed to better target screening (2). In order to establish the main determinants of positive tests for CRC screening at our laboratory, we retrieved results of faecal occult blood tests (FOBT) performed at the Laboratory Medicine department of the University Hospital of Verona, which serves an area with a population of 270,000 inhabitants and a hospital with 750 beds and specialized care units. Results of FOBT tests performed between March 2007 and March 2009 were retrieved from the databases of our Laboratory Information System for 886 outpatients, excluding subjects who underwent this testing for non-screening reasons, as indicated by cancer-specific medications, diagnoses, and procedures. Overall, we identified 306 positive FOBT tests (35%). In multivariate linear regression analysis, age (standardized beta coefficient=0.178; p=0.004) and hemoglobin values (standardized beta coefficient=-0.313; p<0.001), but not sex (standardized beta coefficient = -0.099; p=0.781), were significant predictors of FOBT positive test. After stratifying the study population according to the hemoglobin thresholds for anemia (<132 g/L in men and <122 g/L in women) (3), the prevalence of positive tests was significantly higher among anemic subjects (86% versus 55%; p<0.001 by ÷2 test). Taken together our results further support the suggestion of Walter et al, that CRC screening should be better targeted among older patients by considering comorbidity. Moreover, we have also shown that unexplained anemia is an important determinant of positive FOBT tests, especially among older subjects, so that more attention to this condition is needed to guide CRC screening.

References.

1. Lippi G, Brocco G, Guidi GC. The appropriateness of colorectal cancer screening by fecal occult blood tests. Am J Gastroenterol. 2008;103:800-1.

2. Walter LC, Lindquist K, Nugent S, Schult T, Lee SJ, Casadei MA, Partin MR. Impact of age and comorbidity on colorectal cancer screening among older veterans. Ann Intern Med. 2009;150:465-73.

3. Beutler E, Waalen J. The definition of anemia: what is the lower limit of normal of the blood hemoglobin concentration? Blood. 2006;107:1747-50.

Conflict of Interest:

None declared

Colon Cancer Oncological Terrain-Dependent Inherited Real Risk
Posted on April 15, 2009
Sergio Stagnaro
Researcher, Quantum-Biophysical Semeiotics
Conflict of Interest: None Declared

The paper's conclusions were that advancing age was inversely associated with colorectal cancer screening, whereas comorbidity was a weaker predictor. More attention to comorbidity is needed, to better target screening for older patients with substantial life expectancies and avoid screening older patients with limited life expectancies. I fear that neither the Editors of Annals of Internal Medicine nor the authors know that Oncological Terrain as well as Colon Cancer Oncological Terrain- Dependent Inherited Real Risk, conditio sine qua non of colon cancer, do really exist. Why do doctors have to prescribe colon cancer screening if these congenital pathological conditions, recognized since birth, are absent? (1-7).

References. 1. Stagnaro-Neri M., Stagnaro S. Introduzione alla Semeiotica Biofisica. Il Terreno Oncologico. Travel Factory, Roma, 2004. www.travelfactory.it

2. Stagnaro S. Newborn-pathological Endoarteriolar Blocking Devices in Diabetic and Dislipidaemic Constitution and Diabetes Primary Prevention. The Lancet. March 06 2007. http://www.thelancet.com/journals/lancet/article/PIIS0140673607603316/comments?totalcomments=1

3. Stagnaro S. Rimodellamento Microvascolare, Costituzioni Semeiotico - Biofisiche e Reale Rischio Semeiotico-Biofisico. Ruolo dei Dispositivi Endoarteriolari di Blocco neoformati-patologici www.clicmedicina.it, 10/4/2007, http://www.clicmedicina.it/pagine%20n%2028/rimodellamento.htm

4. Stagnaro S., Stagnaro-Neri M., Le Costituzioni Semeiotico- Biofisiche.Strumento clinico fondamentale per la prevenzione primaria e la definizione della Single Patient Based Medicine. Ed. Travel Factory, Roma, 2004. http://www.travelfactory.it/

5. 1Stagnaro S., Stagnaro-Neri M., Oncological Terrain, conditio sine qua non of Oncogenesis, 2004: http://www.gutjnl.com/cgi/eletters?lookup=by_date&days=60

6. Stagnaro Sergio. Bed-Side Prostate Cancer Detecting, even in early stages ("Real Risk" of Cancer): BMC Family Practice, 2005, 6:24 doi:10.1186/1471-2296-6-24 http://www.biomedcentral.com/1471- 2296/6/24/comments#202466

7. Stagnaro Sergio. Clinical tool reliable in bedside early recognizing pancreas tumour, both benign and malignant. World Journal of Surgical Oncology 2005, 3:62 doi:10.1186/1477-7819-3-62; http://www.wjso.com/content/3/1/62/comments

Conflict of Interest:

None declared

The effect of race and gender on colorectal cancer screening among older veterans
Posted on April 24, 2009
Yu Han
Xijing Hospital, Fourth Military Medical University
Conflict of Interest: None Declared

To the editor:

We read carefully the study by Walter LC and his collegues [1]. They made a conclusion that advancing age was inversely associated with colorectal cancer screening, whereas comorbidity was a weaker predictor. Since they were studying veterans, the patients were predominantly men (96%), and extrapolation of their findings to women must be done with caution. In addition, 87% of the subjects were white. Could the authors comment on the effect of race on colorectal cancer screening among older veterans?

References

1 Walter LC, Lindquist K, Nugent S, Schult T, Lee SJ, Casadei MA, Partin MR. Impact of age and comorbidity on colorectal cancer screening among older veterans. Ann Intern Med. 2009;150:465-73.

Conflict of Interest:

None declared

Submit a Comment

Summary for Patients

How Do Age and Comorbidity Affect the Likelihood of Being Screened for Colorectal Cancer?

The summary below is from the full report titled “Impact of Age and Comorbidity on Colorectal Cancer Screening Among Older Veterans.” It is in the 7 April 2009 issue of Annals of Internal Medicine (volume 150, pages 465-473). The authors are L.C. Walter, K. Lindquist, S. Nugent, T. Schult, S.J. Lee, M.A. Casadei, and M.R. Partin.

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Clinical Slide Sets

Terms of Use

The In the Clinic® slide sets are owned and copyrighted by the American College of Physicians (ACP). All text, graphics, trademarks, and other intellectual property incorporated into the slide sets remain the sole and exclusive property of the ACP. The slide sets may be used only by the person who downloads or purchases them and only for the purpose of presenting them during not-for-profit educational activities. Users may incorporate the entire slide set or selected individual slides into their own teaching presentations but may not alter the content of the slides in any way or remove the ACP copyright notice. Users may make print copies for use as hand-outs for the audience the user is personally addressing but may not otherwise reproduce or distribute the slides by any means or media, including but not limited to sending them as e-mail attachments, posting them on Internet or Intranet sites, publishing them in meeting proceedings, or making them available for sale or distribution in any unauthorized form, without the express written permission of the ACP. Unauthorized use of the In the Clinic slide sets will constitute copyright infringement.

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