A combined nutritional index and mortality in patients with peritoneal dialysis

A combination of multiple nutritional indexes may more comprehensively and favorably reflect dialysis patient’s prognosis. In the present study, we aimed to evaluated the association between total cholesterol/(body mass index × serum albumin) (TC/BA) and mortality in patients with continuous ambulatory peritoneal dialysis (CAPD). We conducted a multicenter retrospective cohort study that included 2907 incident Chinese CAPD patients from seven peritoneal dialysis centers in China between January 1, 2005, and May 31, 2023. The primary outcome was all-cause mortality. We used restricted-cubic-spline plots to explore the shape of the association between TC/BA and outcome. Cause-specific hazard models examined the association between TC/BA and mortality. Of 2907 patients, 754 (25.9%) patients died, including 351 (46.6%) deaths due to cardiovascular disease. A positive linear relationship was observed between TC/BA and all-cause mortality (nonlinear, <i>p</i> = 0.374). In the multivariate cause-specific hazard model, a per-1.0 increase of TC/BA had a 1.29-fold (95% confidence interval [CI] 1.19–1.39) risk of all-cause mortality in the total population. Similar trends were observed in subgroup analyses (all P for interactions &gt; 0.05). Notably, the hazard ratio (HR) of TC/BA (per-1.0 increase) was 1.32 (95% CI 1.23–1.41), 1.29 (95% CI 1.19–1.41), and 1.25 (95% CI 1.22–1.27) times higher than the HR of body mass index (per-1.0 decrease), total cholesterol (per-10 increase), and serum albumin (per-1.0 decrease), respectively. TC/BA was positively linearly related to mortality and may outperform each index in assessing CAPD patient prognosis. The combined nutritional index may more comprehensively and favorably evaluate CAPD patients’ prognosis.