Associations of cardiometabolic multimorbidity and sleep duration with depressive symptom onset and reversion: two longitudinal cohort studies.
BACKGROUND The long-term associations between cardiometabolic multimorbidity (CMM) and depressive symptoms (DS) onset and symptom-state reversion, as well as the potential role of sleep duration in these associations, remain unclear. METHODS We analyzed 14,468 participants from the China Health and Retirement Longitudinal Study (CHARLS) and 8551 from the English Longitudinal Study of Ageing (ELSA). DS was assessed using the CES-D scale; reversion was defined as a transition from DS to non-DS based on CES-D thresholds. Multi-state Markov models estimated transitions among non-DS, DS, and death according to baseline CMM and sleep duration (poor sleep duration defined as <6 or ≥9 h). Cox models evaluated associations with DS onset and reversion. RESULTS In 14,468 Chinese participants (age 59.3 ± 9.5 years; 52.3% female), compared with those without CMDs, participants with one CMD or CMM had 13% and 29% higher hazards of transitioning from non-DS to DS (HR = 1.13 [1.05-1.22]; HR = 1.29 [1.09-1.54]) and 10% and 21% lower hazards of transitioning from DS to non-DS (HR = 0.90 [0.84-0.97]; HR = 0.79 [0.67-0.94]). In 8551 UK participants (age 66.1 ± 9.4 years; 56.2% female), the corresponding higher hazards were 10% and 21% (HR = 1.10 [1.02-1.20]; HR = 1.21 [1.04-1.41]), while hazards of symptom-state reversion were 17% and 26% lower (HR = 0.83 [0.76-0.91]; HR = 0.74 [0.63-0.87]). Significant additive interactions between CMM and unhealthy sleep duration were observed (P for additive interaction <0.001). CONCLUSIONS CMM is associated with higher hazards of DS onset and lower hazards of transitioning from DS to non-DS. Compared with individuals with good sleep duration, these associations were stronger among those with poor sleep duration.