Gunnarsson O, Indridason O S, Franzson L, Sigurdsson G
Department of Endocrinology and Metabolism, Landspitali-University Hospital, University of Iceland, Reykjavik, Iceland.
J Intern Med. 2009 Apr;265(4):488-95. doi: 10.1111/j.1365-2796.2008.02044.x. Epub 2008 Nov 15.
The purpose of this study was to examine factors associated with high or low parathyroid hormone (PTH) levels in relationship to vitamin D insufficiency.
This was a cross-sectional study consisting of 516 healthy men and women, aged 30-85, all Caucasians with vitamin D insufficiency [serum 25(OH)D<45 nmol L(-1)]. The group was divided into quartiles by PTH levels and the highest and lowest quartiles were compared with regard to various factors likely to affect calcium metabolism. We used stepwise multivariable logistic regression to determine the independent association between PTH levels and other variables for men and women separately.
We found that men in the lowest PTH quartile were significantly younger, had less energy intake, lower body mass index (BMI) and better kidney function compared with the highest PTH quartile. They had also higher ionized calcium, insulin-like growth factor (IGF1) and testosterone and were more likely to smoke. Women within the lowest PTH quartile were younger, had lower BMI and magnesium values and higher IGF1 levels and were more likely to smoke. Stepwise multivariate regression showed that IGF1, testosterone and BMI were significantly associated with PTH in men (R(2)=0.472) but smoking, BMI and kidney function in women (R(2)=0.362).
Our results indicate that during vitamin D insufficiency, factors other than calcium and vitamin D may modify PTH response. These factors may be different between sexes and we have identified novel factors, IGF1 and testosterone in men which may be compensatory in nature and confirmed previous factors such as smoking, BMI and kidney function in women.
本研究旨在探讨与甲状旁腺激素（PTH）水平高低相关的因素，及其与维生素D缺乏的关系。
这是一项横断面研究，纳入了516名年龄在30 - 85岁之间的健康白种男性和女性，他们均存在维生素D缺乏[血清25(OH)D<45 nmol/L(-1)]。根据PTH水平将研究对象分为四分位数组，比较最高和最低四分位数组在各种可能影响钙代谢的因素方面的差异。我们分别使用逐步多变量逻辑回归来确定男性和女性PTH水平与其他变量之间的独立关联。
我们发现，与PTH最高四分位数组相比，PTH最低四分位数组的男性明显更年轻，能量摄入更少，体重指数（BMI）更低，肾功能更好。他们的离子钙、胰岛素样生长因子（IGF1）和睾酮水平也更高，且吸烟的可能性更大。PTH最低四分位数组的女性更年轻，BMI和镁值更低，IGF1水平更高，且吸烟的可能性更大。逐步多变量回归显示，IGF1、睾酮和BMI与男性的PTH显著相关（R(2)=0.472），而吸烟、BMI和肾功能与女性的PTH显著相关（R(2)=0.362）。
我们的结果表明, 在维生素D缺乏期间，除钙和维生素D外的其他因素可能会改变PTH反应。这些因素在性别之间可能有所不同，我们已经确定了男性中的新因素IGF1和睾酮，它们可能具有代偿性质，并证实了女性中先前发现的因素，如吸烟、BMI和肾功能。
