Neale R E, Armstrong B K, Baxter C, Duarte Romero B, Ebeling P, English D R, Kimlin M G, McLeod D S A, O Connell R L, van der Pols J C, Venn A J, Webb P M, Whiteman D C, Wockner L
Population Health Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
School of Public Health, University of Sydney, Sydney, Australia.
Contemp Clin Trials. 2016 May;48:83-90. doi: 10.1016/j.cct.2016.04.005. Epub 2016 Apr 14.
Vitamin D, specifically serum 25(OH)D has been associated with mortality, cancer and multiple other health endpoints in observational studies, but there is a paucity of clinical trial evidence sufficient to determine the safety and effectiveness of population-wide supplementation. We have therefore launched the D-Health Trial, a randomized trial of vitamin D supplementation for prevention of mortality and cancer. Here we report the methods and describe the trial cohort.
The D-Health Trial is a randomized placebo-controlled trial, with planned intervention for 5years and a further 5years of passive follow-up through linkage with health and death registers. Participants aged 65-84years were recruited from the general population of Australia. The intervention is monthly oral doses of 60,000IU of cholecalciferol or matching placebo. The primary outcome is all-cause mortality. Secondary outcomes are total cancer incidence and colorectal cancer incidence.
We recruited 21,315 participants to the trial between February 2014 and May 2015. The participants in the two arms of the trial were well-balanced at baseline. Comparison with Australian population statistics shows that the trial participants were less likely to report being in fair or poor health, to be current smokers or to have diabetes than the Australian population. However, the proportion overweight or with health conditions such as arthritis and angina was similar.
Observational data cannot be considered sufficient to support interventions delivered at a population level. Large-scale randomized trials such as the D-Health Trial are needed to inform public health policy and practice.
在观察性研究中，维生素D，特别是血清25(OH)D与死亡率、癌症及其他多种健康指标相关，但缺乏足够的临床试验证据来确定全人群补充维生素D的安全性和有效性。因此，我们开展了D-Health试验，这是一项关于补充维生素D预防死亡和癌症的随机试验。在此，我们报告该试验的方法并描述试验队列。
D-Health试验是一项随机安慰剂对照试验，计划干预5年，并通过与健康和死亡登记册联动进行另外5年的被动随访。65至84岁的参与者从澳大利亚普通人群中招募。干预措施为每月口服60,000IU胆钙化醇或匹配的安慰剂。主要结局是全因死亡率。次要结局是总癌症发病率和结直肠癌发病率。
2014年2月至2015年5月期间，我们招募了21,315名参与者进入试验。试验两组的参与者在基线时均衡良好。与澳大利亚人口统计数据相比，试验参与者报告健康状况为一般或较差、为当前吸烟者或患有糖尿病的可能性低于澳大利亚人口。然而，超重或患有诸如关节炎和心绞痛等健康问题的比例相似。
观察性数据不足以支持在人群层面开展干预措施。需要像D-Health试验这样的大规模随机试验为公共卫生政策和实践提供依据。
