碘盐预防碘缺乏病效果的Cochrane系统评价

A Cochrane systematic review of iodised salt for preventing iodine deficiency disorders

目的 比较碘盐与其它补碘形式或空白食盐预防碘缺乏病的效果。检索策略 检索了Cochrane Library,Med-line,和中国Cochrane中心RCT文献库;手检了《中国地方病学杂志》、《中国地方病防治杂志》、《中华流行病学杂志》、《中华预防医学杂志》、《微量元素与健康杂志》;检索杂志的最近日期至2001年2月;检索资料库的参考文献目录和正进行的研究至2001年11月。纳入标准 试验组为碘盐、对照组为其它供碘方式或空白食盐的前瞻性对照研究,其观察对象为居住在碘缺乏病区的人群,以地甲肿率、尿碘排量、甲状腺激素和甲状腺球蛋白为测量指标。资料收集和分析 由于收集的资料的相似性和质量低,本系统评价未作Meta-分析,但以叙述形式进行总结。主要结果 找到六个符合目的的前瞻性研究,其中,四个为随机照试验,一个为前瞻性的、但未叙述对照组的分配情况,一个为与不同干预措施对照的前瞻性大样本研究。作对照的干预措施包括无碘食盐、碘化水、碘油,以及碘酸钾与碘化钾。观察对象样本量从35到334,大样本量的前瞻性研究大于20000例。虽然不是所有的研究都得到同样的结果,但总的趋势是由于供应了碘盐,地甲肿的发病率减少;虽然从尿碘排量水平反映出并不总是达到了世界卫生组织制定的标准,但在大多数研究中,碘营养状况获得了?

Backgroud Iodine deficiency is the main cause for potentially preventable mental retardation in childhood and is still prevalent in large parts of the world. Objectives To assess the effects of iodised salt in comparison with other forms of iodine supplementation or placebo in the prevention of iodine deficiency disorders. Search strategy We searched the Cochrane Library, Medline, the Register of Chinese trials developed by the Chinese Cochrane Centre, and the Chinese Med Database. We performed handsearching of a number of journals (Chinese Journal of Control of Endemic Diseases, Chinese Journal of Epidemiology, Chinese Journal of Preventive Medicine, and Studies of Trace Elements and Health up to February 2001), and searched reference lists, databases of ongoing trials and the Internet. Date of latest search: November 2001. Selection Criteria We included prospective controlled studies of iodised salt versus other forms of iodine supplementation or placebo in people living in areas of iodine deficiency. Studies reported mainly goitre rates and urinary iodine excretion as outcome measures. Data collection & analysis As the studies identified were not sufficiently similar and not of sufficient quality, we did not do a meta-analysis but summarised the data in a narrative format. Main results We found six prospective controlled trials relating to our question. Four of these were described as randomised controlled trials, one was a prospective trial that did not specify allocation to comparison groups, and one was a large population-based study comparing different interventions. Comparison interventions included non-iodised salt, iodised water, iodised oil, iodation with potassium iodide versus potassium iodate. Numbers of participants in the trials ranged from 35 to 334; over 20 000 people were included in the population-based study. There was a tendency towards goitre reduction with iodised salt, although this was not significant in all studies. There was also an improved iodine status in most studies (except in small children in one of the studies), although urinary iodine excretion did not always reach the levels recommended by the WHO. Reviewers' conclusions The results suggest that iodised salt is an effective and safe means of improving iodine status. However, high quality controlled studies are needed to address questions of dosage and best means of iodine supplementation in different population groups.