Ps-c18-2: body mass index trajectory and technique failure or death in patients initiating peritoneal dialysis

Objective: A decreased body mass index (BMI) over time, as a nutritional status marker, is associated with the poor prognosis of patients undergoing hemodialysis; however, this association has not been studied in patients with peritoneal dialysis (PD). Thus, this study aimed to evaluate the association between BMI trajectory and survival of patients initiating PD. Design and Method: BMI trajectory was defined as percent changes in BMI before PD catheter insertion until six months after insertion. The association of BMI trajectory with technique failure or all-cause death at six months after PD catheter insertion until October 2021 was analyzed. Results: This retrospective cohort study included 122 patients (aged 61.1 ± 12.1 years; 90 males) who underwent PD catheter insertion between January 2008 and March 2020. The median follow-up period was 43.1 (interquartile range, 21.2 - 78.8) months. The mean 6-month percent change in BMI was - 1.98% ± 6.91%, and patients were categorized into tertiles based on BMI trajectory. The adjusted Cox regression analysis for age, sex, Charlson comorbidity index, estimated glomerular filtration rate, and geriatric nutritional risk index revealed a significantly higher rate of technical failure or all-cause mortality (hazard ratio, 2.48; 95% confidence interval: 1.41 - 4.37) in patients with the lowest tertile (T1, BMI trajectory: < - 4.13%) compared to patients with middle tertile, the reference group (T2, BMI trajectory: - 4.13 - 0.67%). The risk was not significantly higher in patients with the highest tertile (T3, BMI trajectory: > 0.67%) than T2 group (hazard ratio: 1.18; 95% confidence interval: 0.66 - 2.11). Conclusions: A decreased BMI (not increased) over time is independently associated with technique failure or all-cause death among patients initiating PD, highlighting the importance of BMI trajectory as a novel prognostic marker. Moreover, further studies are warranted to investigate the interventions, including BMI optimization, as a novel therapeutic target to improve technique and patient survival.