Vitamin D status and its association with parathyroid hormone in 23, 134 outpatients. Issue 220 (June 2022)

• Record Type: Journal Article
• Authors: Chen, Xin; Chu, Chang; Doebis, Cornelia; Xiong, Yingquan; Cao, Yaochen; Krämer, Bernhard K.; von Baehr, Volker; Hocher, Berthold
• Is Part Of: Journal of steroid biochemistry and molecular biology. Issue 220(2022)
• Publication Date: 2022-06
• Subjects: 25-hydroxyvitamin D -- 1, 25-dihydroxyvitamin D -- Parathyroid hormone; Steroid hormones -- Periodicals; Biochemistry -- Periodicals; Hormones -- Periodicals; Molecular Biology -- Periodicals; Hormones stéroïdes -- Périodiques; Steroid hormones; Periodicals; 572.579
• DOI: 10.1016/j.jsbmb.2022.106101
• Languages: English
• ISSNs: 0960-0760

Abstract

Abstract: In vitro studies indicate that 25-hydroxyvitamin D3 (25(OH)D3) and 1, 25-dihydroxyvitamin D3 (1, 25(OH)2D3) inhibits the synthesis of parathyroid hormone (PTH). The degree of PTH inhibition in humans by circulating 25(OH)D and 1, 25(OH)2D may be different. Moreover, age and sex as well as confounding factors like calcium and phosphate may likewise affect the relationship between vitamin D and PTH in humans. However, this was not done so far in adequately powered studies. We investigated the relationship between 25(OH)D as well as 1, 25(OH)2D and intact parathyroid hormone (iPTH) in 23, 134 outpatients (age mean: 59.81 years) from the Berlin-Brandenburg area of Germany with normal serum creatinine considering confounding factors like age, sex, calcium and phosphate. 25(OH)D and iPTH were inversely correlated (r = −0.17, p < 0.0001). The inverse linear correlation was observed over the entire spectrum of 25(OH)D concentrations - from low 25(OH)D concentrations to very high 25(OH)D concentrations. Multiple linear regression analysis revealed that this correlation was independent of age, sex, creatinine, calcium and phosphate (unstandardized coefficients B: −0.16, p < 0.0001). However, 1, 25(OH)2D was only positively associated with iPTH in women (r = 0.05, p = 0.033) and in the subgroup of patients with lower 25(OH)D (25(OH)D< 40 ng/ml) (r = 0.09, p < 0.0001), which was also presented in multiple linear regression analysis (unstandardized coefficients B: 0.20, p = 0.001). Circulating 1, 25(OH)2D does not contribute substantially to the regulation of PTH in middle aged and vitamin D sufficient outpatients from the Berlin-Brandenburg area of Germany with normal kidney function. Presumably, serum 25(OH)D that is converted to 1, 25(OH)2D after uptake in the parathyroid chief cells plays the critical role. Highlights: 25(OH)D and iPTH were inversely correlated across sex and different stages of age in outpatients with normal kidney function. The correlation of 25(OH)D and iPTH was independent of age, sex, creatinine, calcium and phosphate. The inverse correlation of 25(OH)D and iPTH was observed over the entire spectrum of 25(OH)D concentrations. Serum 1, 25(OH)2D was positively associated with iPTH only in the 25(OH)D<40ng/ml subgroup and in women.