High prevalence and mortality risk of nocturia in cardiovascular-kidney-metabolic syndrome: a national cohort study and clinical validation.

BACKGROUND: Nocturia is increasingly recognized as a manifestation of systemic cardiovascular, renal, and metabolic dysfunction, yet its prevalence and prognostic significance within the cardiovascular-kidney-metabolic (CKM) syndrome framework remain unclear. METHODS: We analyzed 11,910 participants from NHANES (2005-2018) and 865 individuals from a hospital-based cohort. Logistic regression assessed associations between CKM stages and nocturia, while Cox proportional hazards models evaluated relationships between nocturia and all-cause and cardiovascular mortality in CKM stages 1-4. Restricted cubic spline analyses explored dose-response relationships. RESULTS: In NHANES, nocturia prevalence increased with CKM stage, from 17.6% in stage 0 to 45.97% in stages 3-4 (P < 0.0001). Compared with stage 0, CKM stages 1-2 and 3-4 were associated with higher odds of nocturia (OR 2.05, 95% CI 1.59-2.64; OR 4.52, 95% CI 3.34-6.10). Nocturia was linked to increased all-cause (HR 1.54, 95% CI 1.34-1.78) and cardiovascular mortality (HR 1.88, 95% CI 1.37-2.57), with significant dose-response relationships. Similar findings were observed in the hospital-based cohort, where CKM stages 1-2 and 3-4 were associated with 2.79-fold and 4.77-fold higher odds of nocturia, respectively. CONCLUSION: Nocturia is common in CKM syndrome and independently associated with increased all-cause and cardiovascular mortality. These findings highlight nocturia as a clinically relevant marker associated with adverse outcomes in CKM populations.