Use of specific drugs for Alzheimer's disease

Objetive. To evaluate the consumption evolution and financial impact of specific treatments for Alzheimer's disease (AD) in Aragon (Spain), analyzing consumption patterns and trends, and to estimate the proportion of AD patients treated with these drugs. Methods. Descriptive study of outpatient utilization of cholinesterase inhibitors and memantine (1996-2004), obtained from the drug packages dispensed by community pharmacists through prescriptions charged to the National Health Service. According to the defined daily doses (DDD) and expenditure data available, data were expressed in DDD per 1,000 inhabitants per day (DHD), DDD per 1,000 inhabitants older than 64 (DHD65), first-last year increase (%), drug consumption pattern, annual cost per inhabitant and daily treatment cost (DTC). To estimate the proportion of treated patients we compared the DHD65 data with the estimated AD prevalence. Results. Overall consumption of these drugs has increased from 0.026 DHD (1996) to 3.235 DHD (2004). Donepezil remains as the most prescribed, though it is proportionally decreasing as a result of the quick introduction of newer alternatives. Overall cost of the DHD dispensed in 2004 reached nearly 6 million euros. DTC decreased about 30% over the study period, but the total cost increased ninety-fold (sixty-fold when non-variable euros from 2004 were considered). According to our estimates, 34% of people with AD were receiving specific treatment. Conclusions. There is a significant increase in the consumption and economical burden of these drugs, whose cost-effectiveness has been questioned in some studies. More studies including specific patient data are needed in order to identify individual characteristics and evaluate treatment appropriateness.