The relationship between body mass index changes and mortality in geriatric peritoneal dialysis patients: a case-control study

BACKGROUND: The prevalence of chronic kidney disease (CKD) is increasing, reflecting the rising incidence of chronic diseases. With the continuous growth of the global geriatric population, a significant portion of individuals with CKD consists of those aged over 65. Regardless of the chosen treatment method, protein-energy loss in patients undergoing renal replacement therapy (RRT) has been associated with elevated morbidity and mortality rates. METHODS: This is a retrospective, single-center study of incident adult PD patients on peritoneal dialysis (PD) from 1998 to 2022. We aimed to compare the survival outcomes of geriatric patients on PD with changing BMI measurements. RESULTS: In the geriatric patient group exhibiting a reduced BMI after dialysis initiation, BMI significantly and negatively influenced survival (p = 0.01). The negative effect of BMI on survival was independent of known risk factors such as diabetes mellitus, a history of cardiovascular disease, gender, residual renal function, and history of hemodialysis before peritoneal dialysis (HD before PD) (p = 0.04). CONCLUSION: Although BMI is easy and extensively measured, it is not considered the perfect monitoring parameter for dialysis patients. However, regular follow-up of BMI, especially in geriatric cases, can be a guiding tool for estimating patients' prognoses.