Charlton Karen, Ware Lisa J, Menyanu Elias, Biritwum Richard Berko, Naidoo Nirmala, Pieterse Chiné, Madurai Savathree Lorna, Baumgartner Jeannine, Asare George A, Thiele Elizabeth, Schutte Aletta E, Kowal Paul
School of Medicine, University of Wollongong, Wollongong, New South Wales, Australia.
Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa.
BMJ Open. 2016 Nov 30;6(11):e013316. doi: 10.1136/bmjopen-2016-013316.
Attempting to curb the rising epidemic of hypertension, South Africa implemented legislation in June 2016 mandating maximum sodium levels in a range of manufactured foods that contribute significantly to population salt intake. This natural experiment, comparing two African countries with and without salt legislation, will provide timely information on the impact of legislative approaches addressing the food supply to improve blood pressure in African populations. This article outlines the design of this ongoing prospective nested cohort study.
Baseline sodium intake was assessed in a nested cohort of the WHO Study on global AGEing and adult health (WHO-SAGE) wave 2 (2014-2015), a multinational longitudinal study on the health and well-being of adults and the ageing process. The South African cohort consisted of randomly selected households (n=4030) across the country. Spot and 24-hour urine samples are collected in a random subsample (n=1200) and sodium, potassium, creatinine and iodine analysed. Salt behaviour and sociodemographic data are captured using face-to-face interviews, alongside blood pressure and anthropometric measures. Ghana, the selected control country with no formal salt policy, provided a nested subsample (n=1200) contributing spot and 24-hour urine samples from the SAGE Ghana cohort (n=5000). Follow-up interviews and urine collection (wave 3) in both countries will take place in 2017 (postlegislation) to assess change in population-level sodium intake and blood pressure.
SAGE was approved by the WHO Ethics Review Committee (reference number RPC149) with local approval from the North-West University Human Research Ethics Committee and University of the Witwatersrand Human Research Ethics Committee (South Africa), and University of Ghana Medical School Ethics and Protocol Review Committee (Ghana). The results of the study will be published in peer-reviewed international journals, presented at national and international conferences, and summarised as research and policy briefs.
为遏制高血压疫情的不断上升，南非于2016年6月实施立法，规定一系列对人群盐摄入量有重大影响的加工食品中的钠含量上限。这项将两个有和没有盐立法的非洲国家进行对比的自然实验，将及时提供有关通过立法手段解决食品供应问题对非洲人群血压影响的信息。本文概述了这项正在进行的前瞻性嵌套队列研究的设计。
在世界卫生组织全球老龄化与成人健康研究（WHO-SAGE）第2波（2014 - 2015年）的嵌套队列中评估基线钠摄入量，这是一项关于成年人健康、福祉及衰老过程的跨国纵向研究。南非队列由全国随机选取的家庭（n = 4030）组成。在一个随机子样本（n = 1200）中收集即时和24小时尿液样本，并分析其中的钠、钾、肌酐和碘含量。通过面对面访谈获取盐摄入行为和社会人口学数据，同时测量血压和人体测量指标。加纳作为选定的没有正式盐政策的对照国家，提供了一个嵌套子样本（n = 1200），该样本来自SAGE加纳队列（n = 5000），并提供即时和24小时尿液样本。两国将于2017年（立法后）进行随访访谈和尿液收集（第3波），以评估人群钠摄入量和血压的变化。
SAGE获得了世界卫生组织伦理审查委员会（参考编号RPC149）的批准，并得到了西北大学人类研究伦理委员会、威特沃特斯兰德大学人类研究伦理委员会（南非）以及加纳大学医学院伦理与方案审查委员会（加纳）的当地批准。研究结果将发表在同行评审的国际期刊上，在国内和国际会议上展示，并总结为研究和政策简报。
