成人碘营养状况评价以及与甲状腺结节的相关性

Correlation between adult iodine nutrition and thyroid nodules

目的：调查成人尿碘水平和膳食碘摄入情况，分析尿碘、膳食碘摄入与甲状腺结节的相关性。方法前瞻性招募2015年1月至3月上海地区健康营养专业人员30名，在自然饮食和生活状态下以“称重法”连续记录3d膳食情况，于膳食第2、3天收集空腹及三餐后2h清洁中段尿（n＝240），检测尿碘含量并计算膳食碘摄入量。完成近3个月食物频率表和甲状腺超声检查。结果空腹及三餐后2 h尿碘中位数为137．56μg／L （91．4～211．5μg／L），碘缺乏、碘充足、碘超足量或过量者分别为20．0％、56．7％和23．3％。个体间尿碘中位数差异较大36．31～359．20μg／L，但空腹与三餐后2 h 尿碘值无显著性差异（ P ＝0．389）。膳食碘摄入量平均值为（197．2±74．2）μg／d，其中食盐和饮用水所提供的碘元素所占比例分别为70．2％和5．4％。膳食碘摄入量与当天尿碘值中位数之间呈显著正相关（r＝0．426， P＝0．019）。甲状腺结节检出组尿碘均值明显高于未检出组[（194．0±101．5）μg／L比（135．7±72．9）μg／L， P＜0．001）]。结论在自然饮食和生活状态下，不同个体碘营养状况差异明显。尿碘值升高与甲状腺结节的发生有关。重复随机尿碘检测结合膳食记录能够减少单一尿碘检测产生的误差，适用个体碘营养状况评价。

Objective To investigate urinary iodine and dietary iodine intake in adults, and to ana-lyze the relationship of urinary iodine and daily dietary iodine intakes with thyroid nodules.Methods To-tally 30 participants with nutritional background were enrolled prospectively from January to March 2015 in Shanghai.The 3-day survey of 24-hour＆#39;s diet record was made using weighting method to evaluate the daily nutrient intakes.On the second and third days of dietary records, urine samples in fasting status and 2 hours after meals were collected from all the participants （n=240）.The levels of urine iodine were meas-ured, and dietary iodine intake calculated.3-month food frequency questionnaire was completed and thy-roid ultrasonography performed.Results The median urinary iodine （ MUI） of fasting and 2 h postprandi-al urine samples was 137.56 μg/L （ 91.4-211.5 μg/L） .The portions of participants with iodine insuf-ficiency, iodine adequate, and iodine above requirements or excess were 20.2%, 56.7%, and 23.3%, respectively.Inter-individual MUI varied from 36.31 μg/L to 359.20 μg/L.No significant difference was found between the fasting urinary iodine and 2 h postprandial urinary iodine （ P=0.389 ） .The average di-etary iodine intake was （197.2 ±74.2） μg/d, and the proportions from iodine salt and drinking water were 70.2% and 5.4%, respectively.There was a significant positive correlation between dietary iodine intake and urinary iodine value of the same day （r=0.426, P=0.019）.Participants with thyroid nod-ules had higher urinary iodine than participants without thyroid nodules [ （ 194.0 ±101.5 ） μg/L vs.＆amp;nbsp;（135.7 ±72.9） μg/L, P〈0.001].Conclusions Inter-individual iodine nutritional status are signifi-cantly different under natural living status.Increased urinary iodine may be related with thyroid nodules. Repeat random urine iodine test combined dietary assessment may reduce the error in evaluating individual iodine nutritional status.