The effectof weather on peritoneal dialysis (PD) prescription: Seasonal variation in PD dialysate utilization

Background: There have been no reports on peritoneal dialysis (PD) solution utilization since this treatment was developed in the 1920s. The aim of the present investigation was to investigate if weather affects PD prescription. Study Design and Methods: This 10-year observational study used the Taiwan National Health Insurance Research Database. Setting and Participants: Claims for different concentrate PD dialysate were analyzed monthly. 2.5% and 4.25% PD solutes were defined as hypertonic solutions. Predictor: Monthly outdoor mean temperature. Outcome and Measurement: The relationship between monthly mean of PD dialysate utilization and monthly outdoor temperature was analyzed by linear regression. Monthly mean PD dialysate utilization amount in 4 quarters was analyzed by ANOVA. Results: During the 10-year study period, a clear seasonal variation in PD dialysate was observed. This seasonal variation was present regardless of age, gender, and the presence of hypertension, diabetes, and dyslipidemia. Monthly mean temperature was positively correlated to 1.5% dialysate utilization amount (r = 0.559, p <0.001) and negatively correlated to 2.5% (r = -0.533, p <0.001) and 4.25% (r = -0.410, p <0.001) dialysate utilization amount. In longitudinal follow-up, hypertonic PD fluid utilization was higher in diabetic patients than in nondiabetic patients from the beginning of treatment. Thereafter, it increased rapidly and reached a plateau within 1 year. Limitations: Analysis of ultrafiltration amount, blood pressure, and body weight was unfeasible due to the nature of the database. Conclusion: The utilization of differential strengths of PD solutions has a seasonal cyclic pattern, with more hypertonic PD solution utilized in winter and more hypotonic PD solution in summer.