Susan L. Norris, MD, MPH; Devan Kansagara, MD; Christina Bougatsos, BS; Rongwei Fu, PhD
Acknowledgment: The following people provided valuable guidance and insights: Mark Helfand, MD, MPH, Evelyn Whitlock, MD, MPH, and Peggy Nygren, MA, of the Oregon Evidence-based Practice Center; Tracy Wolff, MD, MPH, and Mary Barton, MD, MPP, at the Agency for Healthcare Research and Quality; and the U.S. Preventive Services Task Force members Ned Calonge, MD, Russ Harris, MD, MPH, George Isham, MD, MS, and Virginia Moyer, MD, MPH. The authors thank Andrew Hamilton, MLS, MS, for assistance in developing and running search strategies; Peggy Nygren, MA, and Tracy Dana, MLS, for assistance with data abstraction; and Sarah Baird, MS, for technical assistance.
Grant Support: This report was conducted by the Oregon Evidence-based Practice Center under contract to the Agency for Healthcare Research and Quality (contract no. 290-02-0024, Task Order no. 2 for the U.S. Preventive Services Task Force).
Potential Financial Conflicts of Interest: None disclosed.
Requests for Single Reprints: Susan L. Norris, MD, MPH, Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Mail Stop B1CC, Portland, OR 97239.
Current Author Addresses: Drs. Norris and Fu and Ms. Bougatsos: Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Mail Stop BICC, Portland, OR 97239.
Dr. Kansagara: Portland Veterans Administration Medical Center, 3710 SW US Veterans Hospital Road, Portland, OR 97239.
More than 19 million Americans are affected by type 2 diabetes mellitus, which is undiagnosed in one third of these persons. In addition, it is estimated that more than 54 million adults have prediabetes. Debate continues over the benefits and harms of screening and then treating adults who have asymptomatic diabetes or prediabetes.
To update the 2003 U.S. Preventive Services Task Force review on the evidence for potential benefits and harms of screening adults for type 2 diabetes and prediabetes in primary care settings.
MEDLINE and the Cochrane Library for relevant studies and systematic reviews published in English between March 2001 and July 2007.
Trials and observational studies that directly addressed the effectiveness and adverse effects of screening interventions were included. Randomized, controlled trials were used to assess the effectiveness of diabetes and prediabetes treatments. For diabetes interventions, trials of patients with disease for 1 year or less were included, as well as trials comparing outcomes among diabetic and nondiabetic patients.
Relevant data were abstracted in duplicate into a standardized template.
Data were synthesized in a qualitative manner, and a random-effects meta-analysis of the effects of interventions in prediabetes on the incidence of diabetes was performed.
Most of the data on diabetes treatment were not from primary trial data but from subgroup analyses. Participants in intensive lifestyle interventions for prediabetes may not be representative of general prediabetic populations.
Direct evidence is lacking on the health benefits of detecting type 2 diabetes by either targeted or mass screening, and indirect evidence also fails to demonstrate health benefits for screening general populations. Persons with hypertension probably benefit from screening, because blood pressure targets for persons with diabetes are lower than those for persons without diabetes. Intensive lifestyle and pharmacotherapeutic interventions reduce the progression of prediabetes to diabetes, but few data examine the effect of these interventions on long-term health outcomes.
KQ = key question.
Study flow diagram.
KQ = key question. *Cochrane databases were the Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Database of Abstracts of Reviews of Effects. †Other sources were reference lists and expert referrals.
Appendix Table 1. Randomized, Controlled Trials of Hypertension Treatment in Diabetic Populations
Appendix Table 2. Randomized, Controlled Trials of Lipid Interventions in Diabetic and Nondiabetic Populations*
Appendix Table 3. Randomized, Controlled Trials of Interventions in Prediabetes
Diabetes incidence in lifestyle trials.
DPP = Diabetes Prevention Program.
Diabetes incidence in drug trials.
DPP = Diabetes Prevention Program; DREAM = Diabetes Reduction Assessment with Ramipril and Rosiglitazone Medication.
Table 1. Summary of Evidence
Table 2. Number Needed to Screen for Type 2 Diabetes to Prevent 1 Adverse Event after 5 Years of Additional Treatment
Table 3. Number Needed to Screen for Prediabetes to Prevent 1 Case of Diabetes after 3 Years
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.
Norris SL, Kansagara D, Bougatsos C, Fu R. Screening Adults for Type 2 Diabetes: A Review of the Evidence for the U.S. Preventive Services Task Force. Ann Intern Med. ;148:855–868. doi: 10.7326/0003-4819-148-11-200806030-00008
Download citation file:
Published: Ann Intern Med. 2008;148(11):855-868.
Cardiology, Coronary Risk Factors, Diabetes, Endocrine and Metabolism, Guidelines.
Results provided by:
Copyright © 2019 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use