Longitudinal Changes of Cardiothoracic Ratio and Vascular Pedicle Width as Predictors of Volume Status during One Year in Chinese Peritoneal Dialysis Patients

Abstract

Background: Volume overload is an important contributing factor of cardiovascular disease (CVD) in peritoneal dialysis (PD) patients. Vascular pedicle width (VPW) and cardiothoracic ratio (CTR) in routine chest radiograph are indicators of intravascular volume. Longitudinal changes of VPW and CTR may be important prognostic factors of PD patients. Method: We studied 212 PD patients. Longitudinal changes in VPW (ΔVPW) and CTR (ΔCTR) were calculated. The relationship between radiologic measurements and clinical outcome was analyzed. Results: During the 12 months prior to enrollment, VPW rose from 53.35 ± 5.66 to 55.40 ± 6.30 mm (p < 0.001) and CTR rose from 53.3 ± 7.1 to 56.0 ± 7.8% (p < 0.001). After adjusting for confounding variables by Cox regression model, ΔCTR is an independent predictor of hospitalization-free survival; 1% increase in CTR confers 2.9% higher risk of hospitalization (95% confidence interval 0.2–5.7%, p = 0.034). None of the radiologic measurements correlated with actuarial patient survival. Conclusions: In chronic PD patients, ΔCTR is an independent predictor of hospitalization-free survival. This simple radiological parameter may serve as an important parameter for the risk stratification of PD patients.