P1406A CASE-CONTROL STUDY ON RISK FACTORS OF CALCIPHYLAXIS: DATA FROM CHINESE HEMODIALYSIS PATIENTS

Abstract

Abstract Background and Aims Calciphylaxis (CUA) is a rare but potentially fatal disease that is commonly occurred in dialysis patients. Since there is no data based on Chinese population, the study is aimed to investigate risk factors of CUA in Chinese hemodialysis patients. Method We retrospectively evaluated medical records of 20 hemodialysis patients who were newly diagnosed with CUA by skin biopsy admitted to Zhongda Hospital Southeast University from Oct.2017 to Dec.2018. Non-CUA dialysis patients with the same age and duration of dialysis were randomly selected as controls (Ratio=1:2). Results Most of CUA patients were male (80%) and elderly (55%), while 50% had a body mass index higher than 24. The mean time interval since start of dialysis to CUA diagnosis was 114.65±81.32 months, and the median time from appearance of skin lesion to diagnosis was 6 (2, 15) months. The incidence of hyperparathyroidism was higher in patients with CUA (80% vs 62.5%), but the differences of duration of elevated serum intact parathyroid hormone (iPTH) and its highest value were not significant compared with the controls. Warfarin therapy had no significant difference between two groups (15% vs 5%). Univariate logistic regression analysis indicated that male (OR 3.619, 95%CI 1.027-12.748), each 1 point increase in score of use of vitamin D and its analogues (OR 1.505, 1.029-2.201), each 1 mmol/L increase in corrected serum calcium level (OR 24.486, 1.570-381.873), each 1 mmol/L increase in serum phosphate level (OR 5.382, 1.767-16.389), each 1 pg/mL increase in iPTH level (OR 1.002, 1.000-1.003), each 1 g/L decline in serum albumin level (OR 1.181, 1.041-1.340), each 1 IU/L increase in serum alkaline phosphatase (ALP) level (OR 1.005, 1.000-1.009) and each 1 mg/L increase in hypersensitive c-reactive protein level (OR 1.029, 1.000-1.059) were significantly associated with CUA. Serum phosphate, albumin and ALP were still significant risk factors after multivariate analysis. Conclusion This is the first report of risk factors of CUA based on Chinese population. The results show that high levels of serum phosphate and ALP, low level of serum albumin are independent risk factors of CUA in Chinese hemodialysis patients. Unlike previous research from western countries, warfarin therapy didn’t show an increased risk in this study, propably because of the low exposure rate of it in China.