Serum globulin is a novel predictor of mortality in patients undergoing peritoneal dialysis

Abstract

Serum globulin, which is composed mainly of immunoglobulins and acute phase proteins, can be considered as reflecting the inflammatory state. We conducted the present study to investigate the role of globulin in mortality risk in patients undergoing peritoneal dialysis (PD). The study participants were categorized by the median globulin value (2.8 g/dL) as the high globulin group (≥ 2.8 g/dL), and low globulin group (< 2.8 g/dL). Serum globulin is calculated by the equation: (serum total protein-serum albumin). The area under the curve (AUC) by the receiver operating characteristics curve analysis was calculated to compare the mortality prediction capacity of globulin with that of ferritin, and WBC counts. Among the 554 patients, 265 (47.83%) were men, the mean age was 52.91 ± 15.54 years and the body mass index was 23.44 ± 3.88 kg/m². Multivariate Cox models showed the high globulin group had higher mortality risks of all-cause and cardiovascular disease (CVD), compared with the low globulin group with adjusted HRs of 2.06 (95% CI 1.39–3.05) and 1.94 (95% CI 1.18–3.16), respectively. The AUC of univariate and multivariate models for all-cause mortality resulted in higher AUC values for globulin than for ferritin and white blood cell (WBC) counts. In patients undergoing PD, the serum globulin can serve as a novel and independent determinant of predicting overall and CVD- associated mortality.