Time trend in Alzheimer diagnoses and the association between distance to an Alzheimer clinic and Alzheimer diagnosis.

BACKGROUND Centralization of specialized health care in Denmark has caused increased geographical distance to health-care providers, which may be a barrier for Alzheimer patients to seek health care. We examined the incidence of Alzheimer diagnosis in Denmark between 2000 and 2009 and investigated the association between patients' distance to Alzheimer clinics and Alzheimer diagnoses. METHODS Data of all individuals aged 65+ years were collected from Danish national registers. Incidences of Alzheimer diagnoses were analysed with joinpoint regression and hazard ratios (HRs) for Alzheimer diagnoses were analysed with Cox regressions. RESULTS The annual incidence of Alzheimer diagnoses increased with 32.5% [95% confidence interval (CI): 7.1-63.8] among individuals aged 65-74 years from 2000 to 2002 and with 29.1% (95% CI: 11.0-50.2) among individuals aged 75+ years from 2000 to 2003. For both groups, incidence during subsequent years stagnated (0.4%, 95% CI: -1.7 to 2.6; 2.3%, 95% CI: 1.5-6.). From 2008 to 2009, 8605 individuals got an Alzheimer diagnosis. These individuals had a shorter distance to Alzheimer clinics (16.6 vs. 19.1 km, P < 0.001), higher mean age (80.7 vs. 73.7 years, P < 0.001) and were more often women (63.1 vs. 55.9%, P < 0.001). There were inverse associations between distance to Alzheimer clinics and Alzheimer diagnoses (0-19 km: reference; 20-39 km: HR = 0.80, 95% CI: 0.70-0.92; 40-59 km: HR = 0.65, 95% CI: 0.52-0.81). CONCLUSIONS The incidence of Alzheimer diagnoses stagnated from 2002/03 to 2009 in Denmark--a period during which distances to health-care providers in general increased. The inverse association between geographical distance to Alzheimer clinics and Alzheimer diagnoses suggests that distance exclude a segment of the elderly population from an appropriate diagnostic workup and treatment.