Low parathyroid hormone levels after parathyroidectomy reduce cardiovascular mortality in chronic hemodialysis patients.

Abstract

The aim of the study is to elucidate whether parathyroid hormone (PTH) levels after parathyroidectomy affect the prognosis of patients with secondary hyperparathyroidism. Two hundred and ninety-five patients, who underwent PTx without autotransplantation from July 1998 to December 2011, were divided into the low (n=148) and high (n=147) PTH groups, using the median value of each mean value of intact PTH after surgery (16.6pg/mL). After observation for 5.00years, we evaluated demographic factors, influences of postoperative mineral metabolism, magnitude of uremia, and vitamin D receptor activators on their prognosis, with the multivariate Cox proportional hazard model. While overall survival rates in the high and low PTH groups were 54.9 and 74.2%, respectively (P=0.1500), cardiovascular survival rates were 71.6 and 94.4%, respectively (P=0.0256). The hazard ratio for cardiovascular mortality in the high PTH group (≥16.6pg/mL) was 3.132 (P=0.0470), and those in groups with the median age more than 59years and with cardiovascular disease were 2.654 (P=0.0589) and 3.377 (P=0.0317), respectively. The intact PTH level 6days after surgery and the mean postoperative intact PTH value showed a strong correlation (Spearman ρ=0.9007, P<0.0001, y=0.4725x+30.395, R 2=0.51798). The present study suggests that maintaining low PTH levels after parathyroidectomy reduces cardiovascular mortality and improves the prognosis. Total parathyroidectomy (more than 4 glands) without autotransplantation seems to be one of the treatment options for managing severe secondary hyperparathyroidism.