Fourteen relevant studies were identified: two RCTs (n=56); one pseudo-RCT cohort study (n=111); one matched cohort study (n=36); and 10 non-comparative trials (n=106). The non-comparative trials included four case reports (n=14), two single-subject studies (n=10) and four case series (n=82). Both RCTs reported double blinding and one carried out a power analysis. When reported, attrition rates were low.
Comparative studies (four studies): One RCT reported a significant benefit for donepezil compared to routine treatment (effect size 0.86, 95% CI 0.18 to 1.53) using the Mini-Mental State Examination (a general cognitive measure). The second RCT reported a significant benefit for donepezil compared to placebo for general cognitive outcomes using different scales (results for individual cognitive outcomes were reported in the review and showed a significant improvement in short-term memory and attention). The two other studies showed no significant differences between treatment groups, although one study reported a possible benefit with donepezil when administered early in the rehabilitation period.
Noncomparative studies (10 studies): Seven of the 10 studies reported a small to moderate improvement for several cognitive outcomes following treatment with donepezil.
Adverse effects were reported in the review.