Body Roundness Index on the Clinical Outcome of Patients on Peritoneal Dialysis: Analysis of Two Cohorts

Background: Central obesity is common among patients undergoing peritoneal dialysis (PD) and may have important metabolic consequences. The Body Roundness Index (BRI) is a convenient anthropometric measurement that represents central adiposity and visceral fat. However, its prognostic value in PD patients has not yet been explored. Methods: We conducted a retrospective study involving two cohorts of PD patients: an exploratory cohort of 249 prevalent PD patients and a validation cohort of 162 incident ones. In addition to BRI, we performed bioimpedance spectroscopy and other routine clinical and biochemical tests. Outcome measures included patient survival, technique survival, peritonitis-free survival, and hospitalization rates. Results: In the exploratory cohort, the baseline BRI was an independent risk factor for all-cause mortality, with an adjusted hazard ratio of 1.346 (95% CI: 1.094 to 1.655, p = 0.005), and for technique failure, with an adjusted hazard ratio of 1.279 (95% CI: 1.079 to 1.517, p = 0.004). A high BRI was also associated with a higher frequency of hospitalizations (p = 0.001) and longer hospital stays (p = 0.002). In the validation cohort, baseline BRI was also associated with patient survival by univariate Cox regression analysis, but the result became insignificant after adjusting for confounding clinical factors by multi-variable Cox regression. Conclusion: A high BRI is associated with increased rates of all-cause mortality and hospitalization. However, the results from the exploratory and validation cohorts were somewhat inconsistent, indicating the necessity for further research to validate our findings.