Departments of 1Geriatrics.
Centre on Aging and Mobility, University Hospital Zurich, Waid City Hospital, and University of Zurich, Zurich, Switzerland.
Am J Clin Nutr. 2019 Jul 1;110(1):246-253. doi: 10.1093/ajcn/nqz081.
Findings on the effects of vitamin D on cognitive performance have been inconsistent and no clinical trials with detailed cognitive testing in healthy older adults have been reported.
We tested whether 2000 IU is superior to 800 IU vitamin D3/d for cognitive performance among relatively healthy older adults.
We analyzed data on cognitive performance as the secondary outcome of a 2-y double-blind randomized controlled trial that originally investigated the effect of vitamin D3 on knee function and pain in seniors with osteoarthritis. Participants were randomly assigned to either 2000 or 800 IU vitamin D3/d. Capsules had identical appearances and taste. A total of 273 community-dwelling older adults aged ≥60 y were enrolled 6-8 wk after unilateral joint replacement. Inclusion required a baseline Mini Mental State Examination (MMSE) score of 24. We implemented a detailed 2-h cognitive test battery. The primary cognitive endpoint was the score achieved in the MMSE. Secondary endpoints included a composite score of 7 executive function tests, auditory verbal and visual design learning tests, and reaction times.
At baseline, mean age was 70.3 y, 31.4% were vitamin D-deficient [25(OH)D <20 ng/mL], and mean ± SD MMSE score was 28.0 ± 1.5. Although the mean ± SD 25(OH)D concentrations achieved differed significantly between treatment groups at 24-mo follow-up (2000 IU = 45.1 ± 10.2 ng/mL; 800 IU = 37.5 ± 8.8 ng/mL; P < 0.0001), none of the primary or secondary endpoints of cognitive performance differed between treatment group. Results by treatment were similar for predefined subgroups of baseline 25(OH)D status (deficient compared with replete) and age (60-69 y compared with ≥70 y).
Our study does not support a superior cognitive benefit of 2000 IU compared with 800 IU vitamin D/d among relatively healthy older adults over a 24-mo treatment period. This trial was registered at clinicaltrials.gov as NCT00599807.
关于维生素 D 对认知表现影响的研究结果一直不一致，也没有报道过在健康老年人中进行的详细认知测试的临床试验。
我们测试了 2000IU 是否优于 800IU 维生素 D3/d 对相对健康的老年人的认知表现。
我们分析了认知表现作为一项为期 2 年的双盲随机对照试验的次要结果的数据，该试验最初调查了维生素 D3 对老年人骨关节炎膝关节功能和疼痛的影响。参与者被随机分配到 2000IU 或 800IU 维生素 D3/d。胶囊具有相同的外观和味道。共有 273 名年龄在 60 岁以上的社区居住的老年人在单侧关节置换后 6-8 周内入组。入组要求基线 Mini 精神状态检查（MMSE）得分为 24 分。我们实施了详细的 2 小时认知测试组合。主要认知终点是 MMSE 得分。次要终点包括 7 项执行功能测试、听觉言语和视觉设计学习测试以及反应时间的综合评分。
基线时，平均年龄为 70.3 岁，31.4%为维生素 D 缺乏症[25(OH)D<20ng/mL]，平均±SD MMSE 评分为 28.0±1.5。尽管在 24 个月随访时，治疗组之间的平均±SD 25(OH)D 浓度差异显著（2000IU=45.1±10.2ng/mL；800IU=37.5±8.8ng/mL；P<0.0001），但认知表现的主要和次要终点在治疗组之间均无差异。根据基线 25(OH)D 状态（缺乏与充足）和年龄（60-69 岁与≥70 岁）的预设亚组的治疗结果相似。
在 24 个月的治疗期间，我们的研究结果不支持 2000IU 维生素 D 与 800IU 维生素 D/d 相比对相对健康的老年人有更好的认知益处。该试验在 clinicaltrials.gov 上注册为 NCT00599807。
