Psychiatry Research · Mar 20, 2026

Multimorbidity and risk of cognitive impairment: A systematic review and meta-analysis of cohort studies

By Bai J, Li F, Chen Y et al.

BACKGROUND: The long-term relationship between multimorbidity and cognitive impairment remains unclear, and a quantitative synthesis comparing cognitive impairment risks across different multimorbidity patterns is still lacking. This review aimed to systematically synthesize longitudinal evidence on the association between multimorbidity and cognitive impairment, as well as the risk of cognitive impairment across different multimorbidity patterns. METHODS: Six databases were systematically searched from inception to 9 July 2025. Longtitudinal studies examining multimorbidity or multimorbidity patterns in relation to cognitive impairment risk were eligible. Meta-analyses generated pooled HRs and 95% CIs for cognitive impairment across disease counts and multimorbidity patterns. The review followed the PRISMA 2020 guidelines for abstracts. RESULTS: Eighteen cohort studies were included in the review. Multimorbidity was associated with a 49% higher risk of cognitive impairment (95% CI 1.22-1.82). The risk increased steadily with the number of chronic conditions, with HRs ranging from 1.38 (95% CI 1.26-1.51) to 3.57 (95% CI 2.84-4.47) for individuals with two to six or more diseases. Among multimorbidity patterns, the mental health pattern showed the highest risk (HR 2.07, 95% CI 1.86-2.32), followed by the cardiometabolic pattern (HR 2.05, 95% CI 1.92-2.19). Within cardiometabolic disease combinations, coexisting diabetes, stroke, and heart disease conferred the greatest risk. CONCLUSIONS: Multimorbidity is linked to a substantially increased risk of cognitive impairment, underscoring the need for life-course prevention strategies that emphasize early management of chronic conditions, particularly in midlife. Future research should identify optimal management approaches for different multimorbidity patterns and tailor strategies to individual needs.

doi.org/10.1016/j.psychres.2026.117107PubMed 41895026Populations