Effects of climatic region on peritonitis risk, microbiology, treatment, and outcomes: a multicenter registry study

Abstract

Background: The impact of climatic variations on peritoneal dialysis (PD)-related peritonitis has not been studied in detail. The aim of the current study was to determine whether various climatic zones influenced the probability of occurrence or the clinical outcomes of peritonitis.

Methods: Using ANZDATA registry data, the study included all Australian patients receiving PD between 1 October 2003 and 31 December 2008. Climatic regions were defined according to the Köppen classification.

Results: The overall peritonitis rate was 0.59 episodes per patient-year. Most of the patients lived in Temperate regions (65%), with others residing in Subtropical (26%), Tropical (6%), and Other climatic regions (Desert, 0.6%; Grassland, 2.3%). Compared with patients in Temperate regions, those in Tropical regions demonstrated significantly higher overall peritonitis rates and a shorter time to a first peritonitis episode [adjusted hazard ratio: 1.15; 95% confidence interval (CI): 1.01 to 1.31]. Culture-negative peritonitis was significantly less likely in Tropical regions [adjusted odds ratio (OR): 0.42; 95% CI: 0.25 to 0.73]; its occurrence in Subtropical and Other regions was comparable to that in Temperate regions. Fungal peritonitis was independently associated with Tropical regions (OR: 2.18; 95% CI: 1.22 to 3.90) and Other regions (OR: 3.46; 95% CI: 1.73 to 6.91), where rates of antifungal prophylaxis were also lower. Outcomes after first peritonitis episodes were comparable in all groups.

Conclusions: Tropical regions were associated with a higher overall peritonitis rate (including fungal peritonitis) and a shorter time to a first peritonitis episode. Augmented peritonitis prophylactic measures such as antifungal therapy and exit-site care should be considered in PD patients residing in Tropical climates.

Figure 1

— Kaplan-Meier survival curve for peritonitis-free survival for all Australian patients receiving peritoneal dialysis between 1 October 2003 and 31 December 2008, according to climatic region. The difference between the groups was statistically significant (log rank score: 46.8; p < 0.001).

Figure 2

— Cox-adjusted survival curve for peritonitis-free survival for all Australian patients receiving peritoneal dialysis between 1 October 2003 and 31 December 2008, according to climatic region. Compared with temperate-region patients (reference group), tropical-region patients experienced a significantly shorter time to a first peritonitis episode (hazard ratio: 1.18; 95% confidence interval: 1.05 to 1.34).