Bone Mineral Research Center, New York University Winthrop Hospital, Mineola, New York.
Adena Health System, Chillicothe, Ohio.
J Am Geriatr Soc. 2019 Jan;67(1):81-86. doi: 10.1111/jgs.15607. Epub 2018 Oct 25.
To examine the effect of 25-hydroxyvitamin D (25(OH)D) levels recommended by Endocrine Society guidelines (>30 ng/mL) on cognition in healthy older African-American women over 3 years.
Randomized, double-blind, placebo-controlled clinical trial.
Bone Mineral Research Center at New York University Winthrop Hospital.
Healthy postmenopausal African American women aged 65 and older (N=260; mean age 68.2 ± 4.9; 46% college education or higher).
Half of the women were randomized to receive vitamin D (adjusted to achieve a serum level > 30 ng/mL) with calcium (diet and supplement total of 1,200 mg), and half were randomized to receive placebo with calcium (1,200 mg).
Cognitive assessments every 6 months using the Mini-Mental State Examination (MMSE) to detect cognitive decline. Mean MMSE scores were calculated over time for both groups. Those with MMSE scores less than 21 at baseline were excluded.
The average dose of vitamin D was 3,490 ± 1,465 IU per day, and average serum 25(OH)D at 3 years was 46.8 ± 1.2 ng/mL in the active group and 20.7 ± 1.1 ng/mL in the placebo group. Serum 25(OH)D concentration was maintained at greater than 30 ng/mL in 90% of the active group. Over the 3-year period, MMSE scores increased in both groups (p < .001), although change over time was not significantly different between the groups. No adverse events associated with vitamin D were observed.
There was no difference in cognition over time between older African-American women with serum concentrations of 25(OH)D of 30 ng/mL and greater than those taking placebo. There is no evidence to support vitamin D intake greater than the recommended daily allowance in this population for preventing cognitive decline. J Am Geriatr Soc 67:81-86, 2019.
研究内分泌学会指南推荐的 25-羟维生素 D（25(OH)D）水平（>30ng/mL）对超过 3 年的健康老年非裔美国女性认知功能的影响。
随机、双盲、安慰剂对照临床试验。
纽约大学温思罗普医院的骨矿物质研究中心。
健康绝经后年龄在 65 岁及以上的非裔美国女性（N=260；平均年龄 68.2±4.9；46%受过大学教育或以上）。
一半女性被随机分配接受维生素 D（调整血清水平>30ng/mL）和钙（饮食和补充剂共 1200mg），另一半被随机分配接受钙（1200mg）安慰剂。
每隔 6 个月使用简易精神状态检查（MMSE）进行认知评估，以检测认知能力下降。为两组计算随时间推移的平均 MMSE 评分。基线 MMSE 评分低于 21 的人被排除在外。
维生素 D 的平均剂量为每天 3490±1465IU，活性组 3 年后血清 25(OH)D 平均水平为 46.8±1.2ng/mL，安慰剂组为 20.7±1.1ng/mL。活性组中 90%的人维持血清 25(OH)D 浓度大于 30ng/mL。在 3 年期间，两组的 MMSE 评分均增加（p<0.001），但组间随时间的变化无显著差异。未观察到与维生素 D 相关的不良事件。
血清 25(OH)D 浓度为 30ng/mL 及以上的老年非裔美国女性与服用安慰剂的女性相比，认知功能随时间的变化无差异。没有证据支持该人群摄入超过推荐的每日允许量的维生素 D 来预防认知能力下降。J Am Geriatr Soc 67:81-86, 2019.
