Correlation between cognitive impairment and body composition indicators in patients with chronic kidney disease after hemodialysis.

Objective: To examine the relationship between cognitive impairment and body composition indicators in chronic kidney disease (CKD) patients post-hemodialysis.

Methods: This retrospective study included 110 CKD patients admitted to Beijing Luhe Hospital, Capital Medical University between January 2019 and January 2023. General clinical data and body composition indicators were compared between patients with and without cognitive impairment. Multiple logistic regression and ROC curve analysis were used to identify influencing factors and to develop a predictive model.

Results: Cognitive impairment occurred in 50% of the patients post-hemodialysis. No significant differences were found in demographics, disease duration, comorbidities, or hemodialysis duration between the groups (all P > 0.05). However, significant differences were observed in body mass index (BMI) (P < 0.001), lean body mass index (LTI) (P = 0.007), fat tissue index (FTI) (P = 0.024), and total body water (TBW) (P < 0.001). Multiple logistic regression identified TBW (OR 4.900, 95% CI 3.062-7.511, P < 0.001), the TBW/extracellular water (ECW) ratio (OR 7.244, 95% CI 5.092-8.7613, P = 0.016), and the ECW/body cell mass (BCM) ratio (OR 6.720, 95% CI 4.564-8.692, P = 0.030) as independent risk factors for cognitive impairment post-hemodialysis. ROC analysis confirmed their predictive capacity, with AUC values of 0.840, 0.840, and 0.850 respectively. A predictive model incorporating these indicators was developed, showing good calibration (Hosmer-Lemeshow test, P = 0.912) and discrimination (C-index 0.974, 95% CI 0.952-0.997).

Conclusion: Total body water, the TBW/ECW ratio, and the ECW/BCM ratio are independently associated with cognitive impairment in CKD patients post-hemodialysis. Body composition analysis serves as a valuable tool for predicting cognitive impairment in this population, guiding clinicians in assessing cognitive function and planning interventions for these patients.