BACKGROUND: General practitioners (GP) play an important role in detecting cognitive impairment among their patients. OBJECTIVES: To explore factors associated with GPs' judgment of their elderly patients' cognitive status. DESIGN: Cross-sectional data from an observational cohort study (AgeCoDe study); General practice surgeries in six German metropolitan study centers; home visits by interviewers. PARTICIPANTS: 138 GPs, 3,181 patients (80.13 +/- 3.61 years, 65.23% female). MEASUREMENTS: General practitioner questionnaire for each patient: familiarity with the patient, patient morbidity, judgment of cognitive status. Home visits by trained interviewers: sociodemographic and clinical data, psychometric test performance. Multivariate regression analysis was used to identify independent associations with the GPs' judgment of "cognitively impaired" vs. "cognitively unimpaired." RESULTS: Less familiar patients (adjusted odds ratio [aOR] 2.42, 95% CI 1.35-4.32, for poor vs. very high familiarity), less mobile patients (aOR 1.29, 95% CI 1.13-1.46), patients with impaired hearing (aOR 5.46, 95% CI 2.35-12.67 for serious vs. no problems), and patients with greater comorbidity (aOR 1.15, 95% CI 1.08-1.22) were more likely to be rated as "cognitively impaired" by their GPs. CONCLUSIONS: The associations between GPs' assessments of cognitive impairment and their familiarity with their patients and patients' mobility, hearing, and morbidity provide important insights into how GPs make their judgments.
