To evaluate the representation of frail older adults in randomized controlled trials (RCTs), and to assess consequences of under representation by analyzing drug discontinuation rates.
A cohort of older adults newly dispensed donepezil in Ontario between September 2001 and March 2002 was constructed using administrative data. A systematic review of the literature identified RCTs of donepezil. Patients dispensed donepezil were then compared to clinical trial subjects. Discontinuation rates were examined for patients with and without potential contraindications to this drug.
There were 6,424 older adults in the Ontario cohort with new claims for donepezil. Ten RCTs evaluating the use of donepezil were identified (n = 3,423). Between 51% and 78% of the Ontario cohort would have been ineligible for RCT enrollment. Patients dispensed donepezil were older (80.3 vs. 73.7 years, p