Öberg Johanna, Jorde Rolf, Figenschau Yngve, Thorsby Per Medbøe, Dahl Sandra Rinne, Winther Anne, Grimnes Guri
Tromso Endocrine Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, Tromso, Norway.
Diagnostic Clinic, University Hospital of North Norway, Tromso, Norway.
Endocr Connect. 2022 Mar 31;11(3):e210395. doi: 10.1530/EC-21-0395.
Combined hormonal contraceptive (CHC) use has been associated with higher total 25-hydroxyvitamin D (25(OH)D) levels. Here, we investigate the relation between CHC use and vitamin D metabolism to elucidate its clinical interpretation.
The cross-sectional Fit Futures 1 included 1038 adolescents. Here, a subgroup of 182 girls with available 25(OH)D, 1,25-dihydroxyvitamin D (1,25(OH)2D), 24,25-dihydroxyvitamin D (24,25(OH)2D), vitamin D-binding protein (DBP) and measured free 25(OH)D levels, in addition to parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23), was investigated. Vitamin D metabolites were compared between girls using (CHC+) and not using CHC (CHC-). Further, the predictability of CHC on 25(OH)D levels was assessed in a multiple regression model including lifestyle factors. The ratios 1,25(OH)2D/25(OH)D and 24,25(OH)2D/25(OH)D (vitamin D metabolite ratio (VMR)) in relation to 25(OH)D were presented in scatterplots.
CHC+ (n = 64; 35% of the girls) had higher 25(OH)D levels (mean ± s.d., 60.3 ± 22.2) nmol/L) than CHC- (n = 118; 41.8 ± 19.3 nmol/L), P -values <0.01. The differences in 25(OH)D levels between CHC+ and CHC- were attenuated but remained significant after the adjustment of lifestyle factors. CHC+ also had higher levels of 1,25(OH)2D, 24,25(OH)2D, DBP and calcium than CHC-, whereas 1,25(OH)2D/25(OH)D, PTH, FGF23 and albumin were significantly lower. Free 25(OH)D and VMR did not statistically differ, and both ratios appeared similar in relation to 25(OH)D, irrespective of CHC status.
This confirms a clinical impact of CHC on vitamin D levels in adolescents. Our observations are likely due to an increased DBP-concentration, whereas the free 25(OH)D appears unaltered.
联合激素避孕药（CHC）的使用与较高的总25-羟基维生素D（25(OH)D）水平相关。在此，我们研究CHC使用与维生素D代谢之间的关系，以阐明其临床意义。
横断面研究“健康未来1”纳入了1038名青少年。在此，对182名女孩的亚组进行了研究，这些女孩可获取25(OH)D、1,25-二羟基维生素D（1,25(OH)2D）、24,25-二羟基维生素D（24,25(OH)2D）、维生素D结合蛋白（DBP）以及测量的游离25(OH)D水平，此外还包括甲状旁腺激素（PTH）和成纤维细胞生长因子23（FGF23）。比较了使用CHC（CHC+）和未使用CHC（CHC-）的女孩之间的维生素D代谢物。此外，在包含生活方式因素的多元回归模型中评估了CHC对25(OH)D水平的预测能力。以散点图展示了1,25(OH)2D/25(OH)D和24,25(OH)2D/25(OH)D比值（维生素D代谢物比值（VMR））与25(OH)D的关系。
CHC+组（n = 64；占女孩的35%）的25(OH)D水平（均值±标准差，60.3±22.2 nmol/L）高于CHC-组（n = 118；41.8±19.3 nmol/L），P值<0.01。在调整生活方式因素后，CHC+组和CHC-组之间25(OH)D水平的差异有所减弱，但仍具有统计学意义。CHC+组的1,25(OH)2D、24,25(OH)2D、DBP和钙水平也高于CHC-组，而1,25(OH)2D/25(OH)D、PTH、FGF23和白蛋白则显著较低。游离25(OH)D和VMR在统计学上无差异，并且无论CHC状态如何，两种比值与25(OH)D的关系看起来相似。
这证实了CHC对青少年维生素D水平具有临床影响。我们的观察结果可能是由于DBP浓度增加，而游离25(OH)D似乎未改变。
