Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Department of Community and Health Systems, University of Pittsburgh School of Nursing, Pittsburgh, PA, USA.
BMC Geriatr. 2022 Apr 10;22(1):312. doi: 10.1186/s12877-022-02888-w.
Low serum 25-hydroxyvitamin D [25(OH)D] level is associated with a greater risk of frailty, but the effects of daily vitamin D supplementation on frailty are uncertain. This secondary analysis aimed to examine the effects of vitamin D supplementation on frailty using data from the Study To Understand Fall Reduction and Vitamin D in You (STURDY).
The STURDY trial, a two-stage Bayesian, response-adaptive, randomized controlled trial, enrolled 688 community-dwelling adults aged ≥ 70 years with a low serum 25(OH)D level (10-29 ng/mL) and elevated fall risk. Participants were initially randomized to 200 IU/d (control dose; n = 339) or a higher dose (1000 IU/d, 2000 IU/d, or 4000 IU/d; n = 349) of vitamin D3. Once the 1000 IU/d was selected as the best higher dose, other higher dose groups were reassigned to the 1000 IU/d group and new enrollees were randomized 1:1 to 1000 IU/d or control group. Data were collected at baseline, 3, 12, and 24 months. Frailty phenotype was based on number of the following conditions: unintentional weight loss, exhaustion, slowness, low activity, and weakness (≥ 3 conditions as frail, 1 or 2 as pre-frail, and 0 as robust). Cox proportional hazard models estimated the risk of developing frailty, or improving or worsening frailty status at follow-up. All models were adjusted for demographics, health conditions, and further stratified by baseline serum 25(OH)D level (insufficiency (20-29 ng/mL) vs. deficiency (10-19 ng/mL)).
Among 687 participants (mean age 77.1 ± 5.4, 44% women) with frailty assessment at baseline, 208 (30%) were robust, 402 (59%) were pre-frail, and 77 (11%) were frail. Overall, there was no significant difference in risk of frailty outcomes comparing the pooled higher doses (PHD; ≥ 1000 IU/d) vs. 200 IU/d. When comparing each higher dose vs. 200 IU/d, the 2000 IU/d group had nearly double the risk of worsening frailty status (HR = 1.89, 95% CI: 1.13-3.16), while the 4000 IU/d group had a lower risk of developing frailty (HR = 0.22, 95% CI: 0.05-0.97). There were no significant associations between vitamin D doses and frailty status in the analyses stratified by baseline serum 25(OH)D level.
High dose vitamin D supplementation did not prevent frailty. Significant subgroup findings might be the results of type 1 error.
ClinicalTrials.gov: NCT02166333 .
血清 25-羟维生素 D [25(OH)D] 水平较低与衰弱风险增加相关，但每日维生素 D 补充对衰弱的影响尚不确定。本二次分析旨在使用来自了解跌倒减少和维生素 D 研究（STURDY）的数据来研究维生素 D 补充对衰弱的影响。
STURDY 试验是一项两阶段贝叶斯、反应适应性、随机对照试验，纳入了 688 名居住在社区、年龄≥70 岁、血清 25(OH)D 水平较低（10-29ng/ml）和跌倒风险较高的成年人。参与者最初随机分为 200IU/d（对照剂量；n=339）或较高剂量（1000IU/d、2000IU/d 或 4000IU/d；n=349）的维生素 D3。一旦选择 1000IU/d 为最佳较高剂量，其他较高剂量组将重新分配到 1000IU/d 组，新入组者以 1:1 的比例随机分为 1000IU/d 或对照组。数据在基线、3、12 和 24 个月时收集。衰弱表型基于以下情况的数量：非故意体重减轻、疲劳、缓慢、活动减少和虚弱（≥3 项为衰弱，1 项或 2 项为衰弱前期，0 项为稳健）。Cox 比例风险模型估计了在随访时发生衰弱或改善或恶化衰弱状态的风险。所有模型均根据人口统计学、健康状况进行调整，并进一步按基线血清 25(OH)D 水平分层（不足（20-29ng/ml）与缺乏（10-19ng/ml））。
在基线评估有衰弱的 687 名参与者（平均年龄 77.1±5.4 岁，44%为女性）中，208 名（30%）为稳健，402 名（59%）为衰弱前期，77 名（11%）为衰弱。总体而言，与 200IU/d 相比，较高剂量（PHD；≥1000IU/d）对衰弱结局的风险无显著差异。与 200IU/d 相比，比较每个较高剂量时，2000IU/d 组衰弱状态恶化的风险几乎增加了一倍（HR=1.89，95%CI：1.13-3.16），而 4000IU/d 组发生衰弱的风险降低（HR=0.22，95%CI：0.05-0.97）。按基线血清 25(OH)D 水平分层的分析中，维生素 D 剂量与衰弱状态之间无显著关联。
高剂量维生素 D 补充并不能预防衰弱。显著的亚组发现可能是 1 类错误的结果。
ClinicalTrials.gov：NCT02166333。
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