Risk factors associated with secondary hyperparathyroidism in patients with chronic kidney disease

Secondary hyperparathyroidism (SHPT) is common in patients with chronic kidney disease (CKD), and its development and progression are affected by various factors. The aim of the present study was to identify the risk factors for SHPT in patients with CKD. A retrospective study was performed in 498 patients (305 males and 193 females) with CKD, observed in the The First Hospital of Jilin University between January 2008 and December 2012. The demographic, clinical and laboratory data were collected. Patients were divided into the SHPT group (n=424) with elevated serum parathyroid hormone (PTH) expression levels and the control group (n=74) with normal serum PTH expression levels. Univariate and multivariate regression analyses were employed to explore the risk factors for SHPT. Serum PTH expression levels in women with CKD were significantly higher than in men (P=0.047). Serum PTH expression levels were positively correlated with the expression levels of serum creatinine (P<0.01), phosphorus (P<0.01), C-reactive protein (P<0.05), triglyceride (P<0.05), cholesterol (P<0.05) and low-density lipoprotein cholesterol (P<0.05), but were negatively correlated with the expression levels of hemoglobin (P<0.05), calcium (P<0.01) and CO₂ combining power (P<0.01) in patients with CKD. Multivariate analysis showed that the serum expression levels of creatinine [µmol/l; odds radio (OR), 1.003; 95% confidence interval (CI), 1.002-1.004; P=0.001] and phosphorus (mmol/l; OR, 2.19; 95% CI, 1.254-3.826; P=0.006) in patients with CKD significantly influenced serum PTH expression levels. The SHPT risk factors include female gender, low calcium, high phosphorus, acidosis, anemia, hypertension, hyperlipidemia and micro-inflammation, with blood phosphorus and creatinine being independent risk factors.