Lönnroos Eija, Ylilauri Maija, Lamberg-Allardt Christel, Manson JoAnn E, Nurmi Tarja, Uusitupa Matti, Voutilainen Ari, Hantunen Sari, Tuomainen Tomi-Pekka, Virtanen Jyrki K
Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland.
Department of Food and Nutrition, University of Helsinki, Helsinki, Finland.
J Gerontol A Biol Sci Med Sci. 2025 Jun 10;80(7). doi: 10.1093/gerona/glaf077.
Some short-term vitamin D supplementation trials suggest benefits on cognitive performance, but apart from observational studies, there is little evidence whether long-term vitamin D supplementation can prevent development of dementia. We investigated whether vitamin D3 supplementation could affect the incidence of diagnosed dementia in a generally healthy population.
The study included 2 492 participants from the Finnish Vitamin D Trial, free of diagnosed dementia at baseline. They were randomized to placebo, 1 600 IU/d, or 3 200 IU/d of vitamin D3 arm for up to 5 years. Incident diagnoses of dementia were obtained from the national care registries.
The mean age of the participants at baseline was 68.2 years and 42.8% were female. During the mean follow-up of 4.2 years, 18 participants in the placebo arm, 14 participants in the 1 600 IU/d arm (compared to placebo, hazard ratio [HR] = 0.77, 95% confidence interval [CI]: 0.38-1.55), and 13 participants in the 3 200 IU/d arm (HR = 0.72, 95% CI: 0.35-1.48) were diagnosed with dementia. Of the diagnoses, 29 were Alzheimer's disease, without statistically significant differences in the event rates between the 3 arms. Age, sex, or body mass index did not modify the effects. In the subgroup of 550 participants, the mean baseline serum 25-hydroxyvitamin D concentration was 74.8 nmol/L. After 12 months, the mean concentrations were 73.0, 99.7, and 120.4 nmol/L in the placebo, 1 600 IU/d, and 3 200 IU/d arms, respectively.
Five-year, medium-dose or high-dose vitamin D3 supplementation did not affect the dementia incidence in this largely vitamin D-sufficient older population.
ClinicalTrials.gov: NCT01463813, https://clinicaltrials.gov/ct2/show/NCT01463813.
一些短期维生素D补充试验表明其对认知能力有益，但除观察性研究外，几乎没有证据表明长期补充维生素D能否预防痴呆症的发生。我们调查了补充维生素D3是否会影响一般健康人群中已确诊痴呆症的发病率。
该研究纳入了来自芬兰维生素D试验的2492名参与者，他们在基线时未被诊断出患有痴呆症。他们被随机分为安慰剂组、每日1600国际单位组或每日3200国际单位的维生素D3组，为期5年。痴呆症的确诊病例来自国家医疗登记处。
参与者在基线时的平均年龄为68.2岁，42.8%为女性。在平均4.2年的随访期间，安慰剂组有18名参与者、每日1600国际单位组有14名参与者（与安慰剂组相比，风险比[HR]=0.77，95%置信区间[CI]：0.38 - 1.55）、每日3200国际单位组有13名参与者（HR=0.72，95%CI：0.35 - 1.48）被诊断出患有痴呆症。在这些诊断病例中，29例为阿尔茨海默病，三组之间的事件发生率无统计学显著差异。年龄、性别或体重指数并未改变这些影响。在550名参与者的亚组中，基线时血清25 - 羟基维生素D的平均浓度为74.8纳摩尔/升。12个月后，安慰剂组、每日1600国际单位组和每日3200国际单位组的平均浓度分别为73.0、99.7和120.4纳摩尔/升。
在这个维生素D水平总体充足的老年人群中，为期五年的中剂量或高剂量维生素D3补充并未影响痴呆症的发病率。
ClinicalTrials.gov：NCT01463813，https://clinicaltrials.gov/ct2/show/NCT01463813 。
