Background: Knowledge about treatment status can influence effects measured in trials when subjective scales are used.
Objective: The aim of this study was to compare subjective outcomes with objective outcomes of conventional and atypical antipsychotics for neuropsychiatric symptoms (NPS) in dementia.
Methods: We performed a meta-epidemiological study of 38 randomized, placebo-controlled trials. For effectiveness, we used change in NPS and response rate as subjective outcomes, while overall dropout and additional psychotropic use were used as objective outcomes. For side effects, extrapyramidal symptoms (EPS) and somnolence were used as subjective outcomes, while dropout due to adverse events, medication use for EPS, and participants falling were used as objective outcomes.
Results: Conventional antipsychotics reduced NPS more than placebo (standardized mean difference [SMD] - 0.36, 95% confidence interval [CI] - 0.49 to - 0.23), as did atypical antipsychotics (SMD - 0.14, 95% CI - 0.19 to - 0.08). Response rates in the drug groups were also higher. Overall dropout did not differ between conventional antipsychotics and placebo (odds ratio [OR] 1.03, 95% CI 0.77-1.37) or atypical antipsychotics and placebo (OR 1.01, 95% CI 0.89-1.14). Furthermore, additional psychotropic use did not differ. The risk of EPS was higher for conventional (OR 2.93, 95% CI 2.04-4.22) and atypical antipsychotics (OR 1.52, 95% CI 1.23-1.88) versus placebo, as was the risk of somnolence and dropout due to adverse events, but medication use for EPS, as well as risk of falls, was not.
Conclusions: The effectiveness of antipsychotics for NPS in dementia based on subjective scales was not confirmed using objective outcomes, in contrast to the increased risk of side effects.