Objective: To describe the prevalence of cognitive impairment among elderly primary care patients and to compare diagnostic evaluations and use of health services among patients with and those without cognitive impairment.
Design: Prospective cohort study.
Setting: Academic primary care group practice.
Patients: 3954 patients aged 60 years and older who completed the Short Portable Mental Status Questionnaire during routine office visits.
Measurements: Demographics and comorbid illness at baseline, diagnostic evaluations for cognitive impairment, use of standard and preventive health services, use of psychoactive drugs, and death in the year after the screening date.
Results: The prevalence of cognitive impairment among all patients aged 60 years and older at baseline was 15.7%; 10.5% had mild impairment and 5.2% had moderate to severe impairment. Patients with moderate to severe impairment were significantly older than patients with no impairment (76.2 years and 67.4 years, respectively), were more likely to be black (85.8% and 61.3%), had fewer years of education (7.3 years and 9.2 years), and were more likely to have cerebrovascular disease (20.4% and 6.3%) and evidence of undernutrition (30.6% and 16.9%). Dementia was recorded as a diagnosis for less than 25% of patients with moderate to severe cognitive impairment, but patients with documented impairment were more likely to have been evaluated for reversible causes. In the year after screening, patients with moderate to severe impairment were more likely than those with no impairment both to be hospitalized (29.1% and 16.5%) and to visit the emergency department (55.8% and 38.5%) but had fewer outpatient visits (6.0 and 7.6) and greater mortality (8.2% and 2.8%).
Conclusions: Cognitive impairment is associated with increased use of health services and increased mortality. Patients with undocumented cognitive impairment were significantly less likely to be evaluated for reversible causes. Research is needed to determine if better documentation of cognitive impairment would improve not only diagnostic evaluations but also patient management, counseling, and outcomes.