Als C, Keller A, Minder C, Haldimann M, Gerber H
Department of Clinical Chemistry, Inselspital, University of Bern, CH-3010 Bern, Switzerland.
Eur J Endocrinol. 2000 Nov;143(5):629-37. doi: 10.1530/eje.0.1430629.
Before a scheduled increase of salt iodide content up to 20 p.p.m. in Switzerland, urinary iodine concentration (UIC, microg/l) of a randomly selected, area-covering, age-stratified population subgroup was sampled in spring 1997. In contrast to former published studies on UIC, we minimized biases by age, gender, rural/urban, socio-economic and cultural influences.
We contacted 750 households in the Bernese region using random telephone numbers. Per household, one proband selected by play dice collected a spot urine sample. We defined seven age categories: infants, children, adolescents, adults I-III and seniors, aged 0-5, 6-12, 13-20, 21-35, 36-50, 51-65 and >65 years respectively. Randomized UIC data were compared with WHO criteria of iodine deficiency (ID) and previous non-randomized, age-dependent Swiss UIC data. To recruit a perfect random group of volunteers proved difficult, as study participation of adolescent and male populations was somewhat lower than that of elder and female (P<0.005) populations respectively. Study participation of inhabitants of rural and suburban regions was comparable (P=0.139). Out of 413 obtained urine spots, 412 (55%) were analyzed statistically (58% women, 42% men, P<0.005).
Ninety per cent of all UIC values ranged between 25 and 200 microg/l. Median UIC showed mild ID (94 microg/l). UIC varied significantly between age categories (P=0. 0006). Women had lower UIC than men (P=0.014). Infants had no ID. Women in child-bearing age (13-35 years), adults II, adults III and seniors had mild ID. Compared with recommended supplies of 150 and 200 microg I/day in children and male adolescents respectively, we consider their UIC (110 and 144 microg/l) as at least borderline deficient. Absolute UIC was lowest in seniors. Probands from rural/suburban households had similar UICs. Our UIC data were comparable to published ones.
Despite long-term national efforts with iodized salt (15 p.p.m. in 1997), mild ID still prevailed in Bern in spring 1997, with rare extreme UIC values. Mild ID with women in child-bearing age (and probably also with children and male adolescents) was a serious concern, as goiter growth with puberty or pregnancy might be the consequence. Mild ID in adults and seniors might be due to restricted NaCl intake. Results of our randomly selected subgroup from a 650 000 population show that age- and gender-dependency are important when comparing our collected data with published UIC data. This fact must be considered with non-randomly selected population subgroups.
在瑞士计划将碘盐含量提高至20ppm之前，于1997年春季对一个随机选取的、覆盖不同地区、按年龄分层的人群亚组进行尿碘浓度（UIC，微克/升）采样。与以往发表的关于UIC的研究不同，我们尽量减少了年龄、性别、城乡、社会经济和文化因素的偏差。
我们使用随机电话号码联系了伯尔尼地区的750户家庭。每户通过掷骰子选出一名被调查者，采集一份即时尿样。我们定义了七个年龄类别：婴儿、儿童、青少年、成年I - III组和老年人，年龄分别为0 - 5岁、6 - 12岁、13 - 20岁、21 - 35岁、36 - 50岁、51 - 65岁和>65岁。将随机化的UIC数据与世界卫生组织的碘缺乏（ID）标准以及之前非随机的、与年龄相关的瑞士UIC数据进行比较。事实证明，招募一个完全随机的志愿者群体很困难，因为青少年和男性人群的研究参与率分别略低于老年人和女性人群（P<0.005）。农村和郊区居民的研究参与率相当（P = 0.139）。在获得的413份尿样中，412份（55%）进行了统计分析（女性占58%，男性占42%，P<0.005）。
所有UIC值的90%在25至200微克/升之间。UIC中位数显示为轻度碘缺乏（94微克/升）。UIC在不同年龄类别之间有显著差异（P = 0.0006）。女性的UIC低于男性（P = 0.014）。婴儿没有碘缺乏。育龄期女性（13 - 35岁）、成年II组、成年III组和老年人有轻度碘缺乏。与儿童和男性青少年分别推荐的每日150微克和200微克碘摄入量相比，我们认为他们的UIC（110微克/升和144微克/升）至少处于临界缺乏状态。老年人的绝对UIC最低。农村/郊区家庭的被调查者的UIC相似。我们的UIC数据与已发表的数据相当。
尽管国家长期致力于碘盐供应（1997年为15ppm），但1997年春季伯尔尼仍普遍存在轻度碘缺乏，极少出现极端UIC值。育龄期女性（可能还有儿童和男性青少年）的轻度碘缺乏是一个严重问题，因为青春期或孕期甲状腺肿可能会增大。成年人和老年人的轻度碘缺乏可能是由于氯化钠摄入量受限。我们从65万人口中随机选取的亚组结果表明，在将我们收集的数据与已发表的UIC数据进行比较时，年龄和性别依赖性很重要。对于非随机选取的人群亚组，必须考虑这一事实。
