Published online by Cambridge University Press: 13 January 2010
Background: Relatively few studies of mental illness in Africa have focused on dementia. The primary aim of this study was to determine the prescribing patterns and cost of drugs for Alzheimer's disease in a private health care sector patient population.
Methods: A retrospective, exposure-cohort pharmacoepidemiological study was conducted. Data were obtained from a South African private pharmacy group for 2008. The database consisted of 1,578,346 medicine records.
Results: A total of 588 patients (326 females and 262 males) received 2623 medicine items for Alzheimer's disease at a cost of R1,563,701.18 (average cost per item R596.15). The average age of the patients was 75.54 (SD = 10.48) years. Donepezil was the most frequently prescribed active ingredient (37.09%), followed by galantamine (36.94%). Donepezil accounted for 39.50% of the cost of Alzheimer medication. The average cost per prescription was R634.76 for donepezil and R551.35 for memantine. Only 5.27% of patients were prescribed more than one active ingredient for Alzheimer's disease during the year (mostly donepezil or galantamine, and memantine). Average prescribed daily doses (PDDs) of all active ingredients were generally lower than their respective defined daily doses (DDDs). The average PDD for donepezil was 7.45 mg (DDD = 7.5 mg), for galantamine 13.56 mg (DDD = 16 mg), for memantine 17.46 mg (DDD = 20 mg) and for rivastigmine 6.89 mg (DDD = 9 mg).
Conclusions: A small number of patients were prescribed medicine for Alzheimer's disease. It is recommended that qualitative studies be undertaken to determine the cost-effectiveness of the different treatment options according to family members and carers.