Dawson-Hughes B, Harris S S, Dallal G E
Jean Mayer US Department Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston 02111, USA.
Am J Clin Nutr. 1997 Jan;65(1):67-71. doi: 10.1093/ajcn/65.1.67.
Wintertime declines in vitamin D lead to increased concentrations of parathyroid hormone (PTH) and accelerated bone loss in postmenopausal women. We conducted this study to compare calcidiol (25-hydroxyvitamin D) concentrations of men and women, to examine the influence of season, travel, vitamin D intake, and other variables on these concentrations, and to compare associations between calcidiol and PTH concentrations in elderly men and women. In this cross-sectional study of 182 men and 209 women aged > 65 y, mean calcidiol concentrations were higher in men than in women overall (mean +/- SD: 82.4 +/- 35.8 compared with 68.9 +/- 32.1 nmol/L, P < 0.001). In the subset measured in winter (February-May), plasma calcidiol concentrations were lower and not significantly different in men (59.4 +/- 21.8, n = 52) and women (57.7 +/- 23.4 nmol/L, n = 83). In a multiple-regression model, calcidiol concentrations were positively influenced by wintertime travel (P = 0.012), vitamin D intake (P = 0.002), and time spent outdoors (P = 0.096) and negatively influenced by weight (P < 0.001) and age (P = 0.039). Plasma calcidiol and serum PTH concentrations were inversely related, with PTH rising slowly as calcidiol concentrations declined below 110 nmol/L (95 CI: 60, 168 nmol/L). More than 90% of the men and women had calcidiol concentrations below this value in the wintertime. The high prevalence of lower wintertime calcidiol values may increase risk of bone loss in elderly men and women.
冬季维生素D水平下降会导致绝经后女性甲状旁腺激素（PTH）浓度升高及骨质流失加速。我们开展本研究以比较男性和女性的骨化二醇（25-羟维生素D）浓度，探讨季节、旅行、维生素D摄入量及其他变量对这些浓度的影响，并比较老年男性和女性骨化二醇与PTH浓度之间的关联。在这项针对182名男性和209名年龄大于65岁女性的横断面研究中，总体而言男性的平均骨化二醇浓度高于女性（均值±标准差：82.4±35.8对比68.9±32.1 nmol/L，P<0.001）。在冬季（2月至5月）测量的亚组中，男性（59.4±21.8，n = 52）和女性（57.7±23.4 nmol/L，n = 83）的血浆骨化二醇浓度较低且无显著差异。在多元回归模型中，骨化二醇浓度受到冬季旅行（P = 0.012）、维生素D摄入量（P = 0.002）和户外活动时间（P = 0.096）的正向影响，受到体重（P<0.001）和年龄（P = 0.039）的负向影响。血浆骨化二醇和血清PTH浓度呈负相关，当骨化二醇浓度降至110 nmol/L以下（95%置信区间：60, 168 nmol/L）时，PTH缓慢上升。超过90%的男性和女性在冬季骨化二醇浓度低于该值。冬季骨化二醇值较低的高患病率可能会增加老年男性和女性骨质流失的风险。
