Trends of elevated parathormone serum titers in hemodialysis patients on intensive therapy for bone disease: a multicenter study

To determine the prevalence of controlled parathyroid hormone (PTH) serum levels with intensified therapy for chronic kidney disease mineral and bone disorder (CKD-MBD) in the dialysis population, we studied 563 chronic hemodialysis patients recruited from three different dialysis centers from three different major cities in the Kingdom of Saudi Arabia. The trend of the routine monthly chemistries related to CKD-MBD was evaluated besides the whole-molecule PTH serum levels over 28 months (January 2011 to April 2013). The cost ratios of the medications to the estimated dialysis total cost were calculated. There were 323 (57.4%) males in the study, and the mean age of the patients was 50.2±15.2 years; 371 (65.9%) patients were initiated on dialysis before 2011. The causes of the original kidney disease included diabetes mellitus in 163 (29%) patients. Parathyroidectomy was performed in 23 (4.1%) patients and only six (23%) patients underwent the operation during the study period; most of the parathyroidectomies (69%) were performed before 2011. The trend of the medians of monthly serum levels of calcium, phosphorus, albumin, bicarbonate, alkaline phosphatase, serum levels of PTH and vitamin D25 assays showed better control of the levels with time. The added cost of cinacalcet was more significant than the other drugs, including vitamin D and phosphate binders, but the cost was minimal in comparison with the whole dialysis bill. The ratios of the discontinuation rates to the total patient-months of treatment for the different drugs were in the range of 3-4% and mostly due to transient overdosing of medications. We conclude that the trends of the median serum levels of PTH and related minerals in the CKD patients in our dialysis patients suggested a good inclination toward control and prevention of the vascular calcifications prevalent in the CKD-MBD. The popularity of use of new drugs such as cinacalcet is promising and does not seem to add much to the current out-patient cost of chronic dialysis.