Cardiothoracic ratio association with mortality in patients on maintenance peritoneal dialysis

The cardiothoracic ratio (CTR) indicates the left ventricular size; however, the significance of the CTR in patients on maintenance peritoneal dialysis (PD) remains unclear. In this study, 335 PD patients were enrolled and demographic, biochemical, co-morbidity, and dialysis-related data were obtained. The factors determining CTR were further analyzed. All patients were followed up for two years to investigate the mortality risks. We defined a normal CTR as less than the mean CTR value, mild cardiomegaly as a CTR between the mean and mean + 1 SD, and moderate-to-severe cardiomegaly as more than the mean CTR + 1 SD. Among the 335 patients, 163 patients were classified as having a normal CTR (<49.2%), 112 patients as having mild cardiomegaly (CTR 49.2-55.7%), and 60 patients as having moderate-to-severe cardiomegaly (CTR > 55.7%). χ(2) -analysis showed that the incidences of malnutrition and anemia were significantly higher in patients with severe cardiomegaly than in patients of the other groups. The CTR was positively correlated with age, but negatively correlated with albumin and hemoglobin levels. Twenty-six patients (7.7%) had died by the end of the study. Cox multivariate analysis revealed that the CTR significantly predicts all-cause two-year mortality in PD patients on maintenance PD; therefore, the CTR correlates with the nutritional and anemic status of PD patients and is a reliable predictor for all-cause two-year mortality. The analytical results of this study support continued efforts to reduce the CTR and treat underlying causes in patients with cardiomegaly.