Apathy secondary to stroke: a systematic review and meta-analysis.

BACKGROUND Apathy is a disturbance of motivation, frequent in survivors of stroke. Several studies have evaluated the rate of apathy secondary to stroke and risk factors. Different conclusions and contradictory findings have been published. We aimed to perform a systematic review and meta-analysis of all studies evaluating apathy secondary to stroke to better estimate its rate and risk factors, and explore associations with poorer outcomes. METHODS We searched PubMed, Cochrane Library, PsychINFO and PsycBITE databases and screened references of included studies and review articles for additional citations. Search results and data extraction was performed independently. We systematically reviewed available publications reporting investigations on ischemic and intracerebral hemorrhagic stroke and apathy. Quality assessment of the studies was performed independently. Subgroup analyses were performed according to stroke phase (acute and post-acute), stroke past history (first-ever and any-stroke) and patient age (younger and older patients). Pooled odds ratios (OR) and standardized mean difference, and 95% confidence intervals (CI), were derived by random-effects meta-analysis. Heterogeneity was assessed with I(2) test. RESULTS From the initial 1,399 publications, we included 19 studies (2,221 patients). The pooled rate of apathy was 36.3% (95% CI 30.3-42.8; I(2) = 46.8), which was similar for acute [39.5% (95% CI 28.9-51.1)] and post-acute phase [34.3% (95% CI 27.8-41.4)], and about three times higher than the rate of depression [12.1% (95% CI 8.2-17.3)]. Apathetic patients were on average 2.74 years older (95% CI 1.25-4.23; I(2) = 0%). No gender differences were found. Depression (OR 2.29; 95% CI 1.41-3.72; I(2) = 44%) and cognitive impairment (OR 2.90; 95% CI 1.09-7.72; I(2) = 14%) were more frequent and severe in apathetic patients. Apathy rate was similar for ischemic and hemorrhagic stroke type and for left- and right-sided hemispheric lesions. Clinical global outcome was similar between apathetic and nonapathetic patients. CONCLUSION Apathy secondary to stroke is a more frequent neuropsychiatric disturbance than depression. Apathetic patients are more frequently and severely depressed and cognitively impaired. A negative impact of apathy secondary to stroke on clinical global outcome cannot be ascribed. Future research should properly address its predictor factors and evaluate the impact of apathy treatment options in stroke patients.