Estimation of urinary iodine excretion by iodine/creatinine ratio from morning spot urine in school-

• 作 者: Wanqi Zhang Wen Chen Xiaohui Guo Jun Shen Long Tan Laixiang Lin Yan Ye Yalan Wu Wei Wang Wenqiang Wang Wen Jiang Jianchao Bian
• 机 构: Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University,Tianji
• 出 处: 第七届全国中西医结合营养学术会议
• 发表日期: 2016年9期
• 关键词: 24-h urine urinary iodine urinary creatinine iodine/creatinine ratio children

　　Objective: To evaluate the validity of iodine/ereatinine ratio (UI/Cr) from spot urines in estimating 24-h urinary iodine excretion (24-h UIE) in school-age children.Design: A cross-sectional survey.Twice repeated collections of 24-h urine and morning spot urine samples were obtained within one month.24-h urinary iodine concentration (24-h UIC), 24-h urinary creatinine concentration (24-h U-Cr), 24-h urinary volume (24-h U-vol), morning spot urinary iodine concentration (MUIC) and morning spot urinary creatinine concentration (MU-Cr) were measured in all samples.Measured 24-h UIE was calculated by 24-h UIC multiplying 24-h U-vol, while estimated 24-h UIE was calculated by morning spot urinary iodine/creatinine ratio (MUI/Cr) multiplying 24-h urinary creatinine excretion (24-h UCrE).Setting: Ningjin and Lingxian Counties, Shandong, China.Subjects: 981 healthy school-age children Results: No significant differences were observed in MUI/Cr, 24-h UIC and measured 24-h UIE between twice repeated collections.MUI/Cr, 24-h UI/Cr and estimated 24-h UIE were strongly correlated with measured 24-h UIE.The Kappa value α was 0.615 in first collection and 0.599 in second one,demonstrating a good agreement between estimated and measured 24-h UIE.Estimated 24-h UIE was slightly lower than measured 24-h UIE in both collections.Measured 24-h UIE and estimated 24-h UIE were significantly correlated with age.However, no differences were observed in MUI/Cr and 24-h UI/Cr among different ages.Conclusions: Estimated 24-h UIE from morning spot urine could be a valid and reliable alternative for measured 24-h UIE from 24-h urine sample in evaluating individual iodine intake, even though there was 10%~14% underestimation.