Cognitive Impairment Predicts Adverse Outcomes in CKD

Cognitive impairment (CI) affects self-management in chronic diseases, leading to poor decision-making, delayed care, and increased mortality. The specific impact of CI on adverse outcomes in chronic kidney disease (CKD) remains poorly explored.

The French CKD - Renal Epidemiology and Information Network (CKD-REIN) cohort included 3033 patients with CKD stage 2 to 5 and 5 years of follow-up. CI was assessed using the Mini-Mental State Examination (MMSE), and estimated glomerular filtration rate (eGFR) was estimated using the CKD Epidemiology Collaboration creatinine equation. Cox models evaluated the risks of all-cause mortality, kidney replacement therapy (KRT) initiation, and major adverse cardiovascular (CV) events (MACEs).

A total of 3004 patients were included in the analysis (mean age: 67 years, mean eGFR: 34 ml/min per 1.73 m²), and 64%, 23%, and 13%, respectively had MMSE scores > 26, from 24 to 26, and < 24 at baseline. During the follow-up period (mean: 3.87 years), 21.5% of patients initiated KRT, 13.4% died, and 15.3% experienced a MACE before KRT or non-CV death. In adjusted Cox models, patients with a MMSE < 24 had a higher risk of clinical adverse outcome, relative to those with a MMSE > 26: hazard ratio (HR) [95% confidence interval] was 1.42 [1.12-1.81], 1.57 [1.19-2.07], and 1.32 [1.02-1.70] for KRT initiation, all-cause mortality, and MACE, respectively. In addition, CI was associated with all-cause mortality in the MMSE of 24 to 26 group (HR: 1.45, 95% confidence interval: 1.15-1.83).

In CKD, a baseline MMSE score < 24 predicts higher overall-death, KRT initiation, and MACEs, relative to a baseline score > 26. These results highlight CI's prognostic value, and suggest that earlier detection could better personalize management, particularly for kidney and CV complications.