PURPOSE We investigated prevalence, determinants, seasonal changes, and time trends in hypovitaminosis D. We derived a desirable serum 25-hydroxy-vitamin D (25OHD) level in adults/elderly by evaluating the 25OHD-parathyroid hormone (PTH) exponential relationship. METHODS We analyzed serum 25OHD data from a large laboratory database (N = 151,705), from a major academic medical center in Lebanon, from 2009 to 2016. We used cross calibration formulas to convert measured 25OHD levels to LC-MS/MS equivalents based on our external quality assurance protocols. RESULTS 6% of the population were children (mean age 11 ± 5 years, 56% girls), 68% were adults (44 ± 13 years, 71% women), and 25% were elderly (74 ± 6 years, 59% women). The prevalence of hypovitaminosis D, in the entire population, was 39%, 29% and 23% at 25OHD cutoffs of 20 ng/ml, 15 ng/ml, and 12 ng/ml, respectively, across all years. Using multivariate analysis, predictors of 25OHD levels below 12, 15 and 20 ng/ml were younger age, male sex, winter months, and inpatient status both in adults and elderly. In children, older age, female sex, winter months, and inpatient status, predicted levels below 15 ng/ml and 20 ng/ml, but only older age, female sex, and winter months predicted levels below 12 ng/ml. There was a significant steady annual increase in 25OHD levels between 2009 and 2016 of 0.9 ng/ml/year (95% CI: 0.7, 1.0) in children, 1.2 ng/ml/year (1.2, 1.3) in adults and 2.6 ng/ml/year (2.6, 2.8) in the elderly. Using best fit non-linear regression models, on a subset of adults and elderly in whom concomitant 25OHD and PTH data was available (N = 4025), PTH levels plateaued at a serum 25OHD level of 26.1 ng/ml. CONCLUSION Secular increase in serum 25OHD levels is observed in Lebanon, but hypovitaminosis D is still prevalent. Our data provides basis for a desirable 25OHD level above 26 ng/ml in adult and elderly Lebanese individuals.

中文翻译：

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整个生命过程中维生素D低水平的时间趋势和预测因子：2009-2016年。

目的我们调查了维生素D缺乏症的患病率，决定因素，季节变化和时间趋势。通过评估25OHD-甲状旁腺激素（PTH）的指数关系，我们得出了成年人/老年人中理想的血清25-羟基维生素D（25OHD）水平。方法我们分析了2009年至2016年来自黎巴嫩主要学术医学中心的大型实验室数据库（N = 151,705）的血清25OHD数据。我们使用交叉校准公式将测得的25OHD水平转换为基于我们的外部质量保证协议。结果人口的6％为儿童（平均年龄11±5岁，女孩56％），68％为成年人（44±13岁，女性71％），25％为老年人（74±6岁，59％女性） ）。在20 ng / ml，15 ng / ml的25OHD临界值下，维生素D缺乏症的总体患病率分别为39％，29％和23％，和所有年份分别为12 ng / ml和12 ng / ml。使用多变量分析，预测25OHD水平低于12、15和20 ng / ml的预测因素是年轻人，男性，冬季和成年人和老年人的住院状况。对于年龄较大，女性，冬季和住院状态的儿童，预测水平低于15 ng / ml和20 ng / ml，但只有年龄较大，女性，冬季的儿童预测水平低于12 ng / ml。在2009年至2016年期间，儿童的25OHD水平每年稳定地显着增加，分别为0.9 ng / ml /年（95％CI：0.7、1.0），成人1.2 ng / ml /年（1.2、1.3）和2.6 ng / ml。毫升/年（2.6，2.8）。使用最佳拟合非线性回归模型，在可获得25OHD和PTH数据（N = 4025）的一部分成年人和老年人中，PTH水平稳定在26.1 ng / ml的血清25OHD水平。结论在黎巴嫩观察到血清25OHD水平的长期增加，但维生素D缺乏症仍很普遍。我们的数据为成人和老年人黎巴嫩人的理想25OHD水平高于26 ng / ml提供了依据。