The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.
Department of Physiotherapy, Jehangir Hospital, Pune, Maharashtra, 411001, India.
Osteoporos Int. 2019 Jan;30(1):93-101. doi: 10.1007/s00198-018-4705-4. Epub 2018 Sep 25.
Three hundred eighty-seven home-dwelling older women were divided into quartiles based on mean serum 25-hydroxyvitamin D (S-25(OH)D) levels. The rates of falls and fallers were about 40% lower in the highest S-25(OH)D quartile compared to the lowest despite no differences in physical functioning, suggesting that S-25(OH)D levels may modulate individual fall risk.
Vitamin D supplementation of 800 IU did not reduce falls in our previous 2-year vitamin D and exercise RCT in 70-80 year old women. Given large individual variation in individual responses, we assessed here effects of S-25(OH)D levels on fall incidence.
Irrespective of original group allocation, data from 387 women were explored in quartiles by mean S-25(OH)D levels over 6-24 months; means (SD) were 59.3 (7.2), 74.5 (3.3), 85.7 (3.5), and 105.3 (10.9) nmol/L. Falls were recorded monthly with diaries. Physical functioning and bone density were assessed annually. Negative binomial regression was used to assess incidence rate ratios (IRRs) for falls and Cox-regression to assess hazard ratios (HR) for fallers. Generalized linear models were used to test between-quartile differences in physical functioning and bone density with the lowest quartile as reference.
There were 37% fewer falls in the highest quartile, while the two middle quartiles did not differ from reference. The respective IRRs (95% CI) for falls were 0.63 (0.44 to 0.90), 0.78 (0.55 to 1.10), and 0.87 (0.62 to 1.22), indicating lower falls incidence with increasing mean S-25(OH)D levels. There were 42% fewer fallers (HR 0.58; 040 to 0.83) in the highest quartile compared to reference. Physical functioning did not differ between quartiles.
Falls and faller rates were about 40% lower in the highest S-25(OH)D quartile despite similar physical functioning in all quartiles. Prevalent S-25(OH)D levels may influence individual fall risk. Individual responses to vitamin D treatment should be considered in falls prevention.
387 名居家老年女性根据血清 25-羟维生素 D（S-25（OH）D）平均水平分为四等份。尽管身体机能没有差异，但最高 S-25（OH）D 四分位组的跌倒率和跌倒者比例比最低四分位组低约 40%，这表明 S-25（OH）D 水平可能调节个体跌倒风险。
我们之前的一项为期 2 年、针对 70-80 岁女性的维生素 D 和运动随机对照试验中，补充 800IU 维生素 D 并未降低跌倒发生率。鉴于个体对个体反应的个体差异很大，我们在此评估了 S-25（OH）D 水平对跌倒发生率的影响。
不论原始分组如何，对 387 名女性的数据按 6-24 个月期间 S-25（OH）D 水平的四分位数进行探索；平均值（SD）分别为 59.3（7.2）、74.5（3.3）、85.7（3.5）和 105.3（10.9）nmol/L。每月使用日记记录跌倒情况。每年评估身体机能和骨密度。使用负二项式回归评估跌倒的发病率比（IRR），并使用 Cox 回归评估跌倒者的风险比（HR）。使用广义线性模型以最低四分位数为参考检验身体机能和骨密度的四分位间差异。
最高四分位组的跌倒率降低了 37%，而中间两个四分位组与参考值无差异。相应的跌倒发生率 IRR（95%CI）分别为 0.63（0.44 至 0.90）、0.78（0.55 至 1.10）和 0.87（0.62 至 1.22），表明 S-25（OH）D 水平升高与跌倒发生率降低相关。与参考值相比，最高四分位组的跌倒者减少了 42%（HR 0.58；0.40 至 0.83）。四个四分位组之间的身体机能无差异。
尽管所有四分位组的身体机能相似，但最高 S-25（OH）D 四分位组的跌倒率和跌倒者比例仍降低了约 40%。普遍的 S-25（OH）D 水平可能会影响个体跌倒风险。在预防跌倒时应考虑个体对维生素 D 治疗的反应。
