Postoperative changes in 25-hydroxy vitamin D and parathyroid hormone levels in obese patients / 中华临床营养杂志

ABSTRACT

Objective:To investigate the postoperative changes in levels of 25-hydroxy vitamin D (25-[OH]D], parathyroid hormone (PTH) and other relevant biomarkers in obese patients receiving metabolic surgery and analyze the dynamic changes in relevant biomarkers in the short term (after 3-6 months) and the long term (after 12-24 months).Methods:A total of 96 obese patients who underwent metabolic surgery and received follow-up examinations from January 2018 to January 2020 were included. Baseline and postoperative data were collected, including anthropometric data (height, weight, neck circumference, waistline and hipline) and laboratory test results (fasting glucose, glycated hemoglobin, 25-[OH)D, PTH, serum calcium and serum phosphorus). Body mass index (BMI) and waist-hip ratio were calculated. The anthropometric data were analyzed by repeated measures analysis of variance and laboratory data were compared between groups using t test and Kruskal-Wallis test. Results:96 patients (33 males and 63 females) were included, of whom 49 were complicated with diabetes. Prior to surgery, 79 (79.17%) of the patients had 25-(OH)D deficiency (< 20 μg/L), 16 (16.67%) had 25-(OH)D insufficiency (≥ 20 μg/L and < 30 μg/L) and 23 (23.96%) had high PTH levels (> 70 ng/L). After the surgery, 25-(OH)D level was transiently increased in the short term ( P = 0.01) but declined thereafter in the long term ( P < 0.01) to levels lower than baseline ( P = 0.023). Long-term PTH level was higher than baseline ( P = 0.012), with 11 patients showing PTH levels higher than normal (> 70 ng/L). Serum phosphorus level was increased in both the short term and the long term ( P < 0.01). Conclusions:Obese patients have 25-(OH)D deficiency/insufficiency before metabolic surgery and experience further decrease in the long term after surgery, despite a transient increase. Secondary increase in PTH level occurs in some of the patients after surgery. Long-term nutritional supplements and comprehensive nutritional management play important roles in postoperative management of obese patient.