O'Dowd K J, Clemens T L, Kelsey J L, Lindsay R
Division of Epidemiology, Columbia University School of Public Health, New York, New York.
J Am Geriatr Soc. 1993 Apr;41(4):414-21. doi: 10.1111/j.1532-5415.1993.tb06950.x.
To determine the role and relative importance of sources of exogenous calciferol (vitamin D) in maintaining vitamin D endocrine status in the mid-winter and early spring in a representative sample of institutionalized elderly persons in the New York City area.
Cross-sectional survey.
A privately-run urban nursing home and the long-term care unit of a suburban public hospital.
Residents aged 60 years and older scheduled for a routine annual physical examination and an additional group of individuals ascertained by random sampling. Those with a history of anti-convulsant or glucocorticoid use, liver disease, chronic renal disease (or serum creatinine > 1.5 mg/dL), parathyroid disease, Paget's disease, gastric surgery, or pharmacological vitamin D use were excluded. Of 301 sampled individuals, 221 were found eligible to participate, and 109 were successfully enrolled.
The average vitamin D intake was 379 IU/day (range 55-1006 IU/day) and total vitamin D intake was below the Recommended Dietary Allowance in 16% of subjects. Fifty percent of total vitamin D intake came from fortified milk, and 26% came from vitamin supplements. Vitamin supplement use was not associated with low dietary intake. Among subjects taking a supplement containing 400 IU/day, none had serum calcidiol levels below 15 ng/mL, while among subjects with vitamin D intake between 200 and 400 IU/day, 46% had serum calcidiol levels below 15 ng/mL and 14% had calcidiol levels below 10 ng/mL. Vitamin D intake from non-supplement sources (but not from supplements) appeared to have a negative association with serum calcitriol levels.
Many nursing home residents may require vitamin supplements in order to achieve optimal levels of calciferol replacement. The choice of a vehicle for calciferol replacement may affect calcitriol levels.
在纽约市地区有代表性的一组机构养老老年人样本中，确定外源性骨化醇（维生素D）来源在维持冬末和早春维生素D内分泌状态中的作用及相对重要性。
横断面调查。
一家私立城市疗养院和一家郊区公立医院的长期护理病房。
计划进行年度常规体检的60岁及以上居民，以及通过随机抽样确定的另一组个体。排除有抗惊厥药或糖皮质激素使用史、肝病、慢性肾病（或血清肌酐>1.5mg/dL）、甲状旁腺疾病、佩吉特病、胃部手术或使用药理维生素D史的个体。在301名抽样个体中，发现221名符合参与条件，109名成功入组。
维生素D平均摄入量为379IU/天（范围55 - 1006IU/天），16%的受试者总维生素D摄入量低于推荐膳食摄入量。总维生素D摄入量的50%来自强化牛奶，26%来自维生素补充剂。使用维生素补充剂与低膳食摄入量无关。在每天服用含400IU补充剂的受试者中，无人血清骨化二醇水平低于15ng/mL，而在维生素D摄入量为200至400IU/天的受试者中，46%的人血清骨化二醇水平低于15ng/mL，14%的人骨化二醇水平低于10ng/mL。非补充剂来源（而非补充剂）的维生素D摄入量似乎与血清骨化三醇水平呈负相关。
许多疗养院居民可能需要维生素补充剂以达到最佳的骨化醇替代水平。骨化醇替代载体的选择可能会影响骨化三醇水平。
