Persistently low intact parathyroid hormone levels predict a progression of aortic arch calcification in incident hemodialysis patients

Recent observational studies have found that low intact parathyroid hormone (iPTH) is related with mortality in hemodialysis patients and these findings may be considered to be the result of accelerated cardiovascular calcifications in adynamic bone disease. This study was aimed to determine the relationship between persistently low iPTH and aortic arch calcification (AAC) in incident hemodialysis patients. From January 2004 to December 2008, a total of 94 incident hemodialysis patients were enrolled in this study. They were divided into three groups according to the changing patterns of iPTH during the first year of hemodialysis. ACC was scored on posterior-anterior plain chest X-rays using a specific scale at the initiation of dialysis and followed till May 2011. The median follow-up periods were 46.9 months. The prevalence of baseline AAC and its progression were the highest in the persistently low iPTH group. Also, all-cause mortality was the highest in this group. Age, baseline calcification score and persistently low iPTH independently contributed to the progression of calcification by multivariate logistic regression analyses (HR 1.083, 95% CI 1.023-1.147, P = 0.006; HR 3.320, 95% CI 1.023-10.789, P = 0.046; HR 5.207, 95% CI 1.027-26.412, P = 0.046, respectively). Also, mortality was relatively higher in calcification progressor compared to non-progressor (39.3, 18.2%, P = 0.030). Persistently low iPTH was an independent risk factor for both AAC and mortality in incident hemodialysis patients.