Primary care expenditures before the onset of Alzheimer’s disease

OBJECTIVE: To investigate primary care expenditures in the period before diagnosis of AD. METHODS: In a population-based sample of Medicare enrollees in New York City, person-level 1996 Medicare claims, summed over primary care encounters, were examined for people who developed AD in 1997 to 1998 and those who did not. RESULTS: People who developed AD were more likely to use Medicare outpatient and ambulatory care 1 to 2 years before diagnosis. Compared with respondents who did not develop AD, the excess cost for men was 1, 167 (85% higher) and for women 239 (26% higher). Among elderly people > or = 75 years in the United States, the prodromal period of AD was associated with an excess Medicare-based primary care cost of 128. 5 to 194. 7 million. CONCLUSION: In addition to huge costs associated with AD after diagnosis, prediagnosis costs are an unrecognized source of expenditures related to the disease.