Insomnia as risk factor for brain, mental and general health consequences: an umbrella systematic review

SUMMARY (200 words) Sleep quality is a determinant of health, and insomnia could be a key factor for preserving brain health. We searched MEDLINE and EMBASE (last search August 2025) to identify systematic reviews with meta-analysis (SMRAs) that evaluated insomnia as a predictive factor of dementia, stroke, depression, suicide, death, occupational injuries, and hospitalization. Sixteen SMRA were included, and three additional original systematic reviews were conducted for stroke, occupational injuries and hospitalization, as no published SMRAs were found on these topics. SRMAs consistently identified insomnia as a predictor of dementia, depression, suicide, while death was not associated with this disorder. Our two original SMRAs revealed that insomnia as a predictor of stroke (9 studies, 1,343,164 participants, HR= 1.26, 95%CI 1.05-1.53) and hospitalization for any reason (5 studies, 517,620 participants, OR=1.28, 95%CI 1.14-1.43). With regard to occupational injuries, it was not possible to perform a meta-analysis of the results of the two studies retrieved (143,942 participants). Although an association was found with unintentional fatal injuries and with commuting injuries, data should be considered insufficient to draw a conclusion on this outcome. This work contributes in better defining the association between insomnia and the key descriptors of brain health and possible links to general health.