Abstract: Objective To investigate the influence factors for serum iPTH (intact parathyroid hormone, 1-84 PTH), and the relationship between low serum PTH,malnutrition, inflammation, and adynamic bone disease in hemodialysis patients. Methods A total of 162 maintenance hemodialysis patients were divided into low PTH group (iPTH≤150 pg/ml; n=77) and control PTH group (150 pg/ml＜iPTH ≤600 pg/ml;n=85). Anthropometrical parameters including triceps skin fold (TSF), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC) and body mass index (BMI) were collected. Serological markers including iPTH, Creactive protein (CRP), prealbumin (PA), albumin (ALB), total iron binding capacity (TIBC), serum calcium, serum phosphorus, triglyceride (TG), low density lipoprotein (LDL), total cholesterol (TC), interleukin 1β (IL-1β), interleukin 6 (IL-6) and bone alkaline phosphatase (BALP) were assayed. Albumin corrected calcium and calcium phosphorus product (Ca×P) were calculated. Malnutrition inflammation score (MIS) was assessed for nutritional status. Results Serum iPTH was negatively correlated with CRP (r=-0.297, P＜0.05), IL-1β (r=-0.334, P＜0.05) and albumin corrected calcium (r=-0.393, P＜0.01), and positively correlated with
PA (r=0.426, P＜0.01), serum phosphorus (r=0.579, P＜0.01) and Ca×P (r=0.432, P＜0.01). PA was significantly lower in low PTH group than in control PTH group (349.75±78.29 g/L vs. 393.47±75.02 g/L, P＜0.05), while CRP, IL- 1β and MIS were significantly higher in low PTH group than in control PTH group [4.99 ± 3.40 mg/l vs. 3.28 ± 1.79 mg/l, P＜0.05 for CRP; 1476.09 (563.63～4020.16) pg/ml vs. 659.31 (466.79～1888.53) pg/ml, P＜0.05 for IL-1β; 12.23±5.59 vs. 9.0±4.23, P＜0.05 for MIS], indicating that low serum PTH is associated with malnutrition inˇammation complex syndrome (MICS). Serum BALP was generally low within 0.61～5 μg/L, indicating the lower bone metabolism rate in all hemodiaysis patients. Conclusion Serum iPTH was related to serum CRP, IL-1β, PA, albumin corrected calcium, serum phosphorus and Ca×P product. Low serum PTH was associated with MICS. Low serum BALP found in all hemodiaysis patients indicated lower bone metabolism rate. Appropriate intervention to improve nutritional status and to inhibit inflammation may be helpful in patients with low serum PTH and adynamic bone disease.

Key words: Hemodiaysis, Low serum PTH, Malnutrition Inflammation Complex Syndrome（MICS）, Adynamic bone disease