Cognitive reserve and cognition in mood disorders: A systematic review and meta-analysis

•Cognitive functioning heterogeneity is a well-recognized phenomenon in individuals diagnosed with mood disorders.•Cognitive reserve has been linked to multiple positive outcomes, including cognitive performance in these patients.•Cognitive reserve was found to be associated with performance in all cognitive domains, and meta-regression analyses unveiled that the duration of illness, sex, and severity of depression may play a substantial role in shaping the association between CR and cognitive functioning.•CR emerges as a possible protective factor for cognitive functioning in adult individuals with mood disorders, potentially helping to mitigate the cognitive impairments associated with the disorder. Cognitive functioning heterogeneity is a well-recognized phenomenon in individuals diagnosed with mood disorders. Cognitive Reserve (CR) has been linked to multiple positive outcomes, including cognitive performance in these patients. This systematic review and meta-analysis aim to provide a comprehensive analysis of the relationship between CR and cognitive functioning in individuals with mood disorders, including bipolar disorder and depressive disorders. Following PRISMA guidelines, a systematic review and meta-analysis was conducted of original research exploring the relationship between CR and cognitive performance in adult individuals with mood disorders. The literature search was conducted on PubMed, Scopus, and Web of Science, from 2002 to September 2023, and the Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of studies. Overall, 17 studies met the inclusion criteria for the systematic review and 11 for the meta-analysis. Both qualitative and quantitative findings suggested a positive relationship between CR measures and cognitive domains. CR emerges as a possible protective factor for cognitive functioning in adult individuals with mood disorders, potentially helping to mitigate the cognitive impairments associated with the disorder. These findings underscore the importance of the fact that promoting and enhancing CR could help in the cognitive prognosis of this population.