title: A cross-sectional comparison study on the iodine nutritional status between rural and urban residents in Zhejiang Province, China.
abstract: OBJECTIVE
  To evaluate the difference of iodine nutritional status between rural and urban residents under the universal salt iodisation policy.
  
  
  METHODS
  A multistage cluster sampling technique was employed in the present cross-sectional study. In total, 3300 rural and 3300 urban households were selected where the investigation was conducted.
  
  
  METHODS
  A total of 8553 rural and 8909 urban residents participated in this provincial survey.
  
  
  METHODS
  Spot urine samples were collected and the iodine concentration in urine was determined by the modified acid-digestion method.
  
  
  RESULTS
  The median urinary iodine concentration of rural residents was 170.1 μg/L, which was higher than that of urban residents with 153.5 μg/L. For school-aged children, middle-aged people and older people, the median urinary iodine concentration of rural residents was 191.2, 160.2 and 154.0 μg/L, respectively, which was higher than that of urban residents with 166.2, 153.8 and 129.5 μg/L, respectively. Risk factors for urinary concentration of rural residents were age (OR=0.99), terrain (OR=0.83), usual intake of pickled products (OR=1.45) and non-iodised salt intake (OR=0.39), while those for urban residents were age (OR=0.99), terrain (OR=0.83), usual intake of aquatic products (OR=1.24) and non-iodised salt intake (OR=0.27) compared with iodised table salt intake.
  
  
  CONCLUSIONS
  The median urinary iodine concentration of rural residents was higher than that of urban residents although they were both falls in optimal iodine status as recommended by WHO/UNICEF/International Council for the Control of Iodine Deficiency Disorders. Iodised salt intake is the major factor which influences the iodine nutritional status mostly for rural and urban residents. The ongoing monitoring of population iodine status remains crucially important.
authors: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
authors: Yan
authors: Y
authors: Zou
authors: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
authors: Xiaoming
authors: X
authors: Lou
authors: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
authors: Gangqiang
authors: G
authors: Ding
authors: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
authors: Zhe
authors: Z
authors: Mo
authors: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
authors: Wenming
authors: W
authors: Zhu
authors: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
authors: Guangming
authors: G
authors: Mao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002681:China; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007455:Iodine / Q000652:urine*; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D012424:Rural Population; D017673:Sodium Chloride, Dietary; D014505:Urban Population; D055815:Young Adult
chemical_list: D017673:Sodium Chloride, Dietary; C034024:iodized salt; D007455:Iodine
keywords: EPIDEMIOLOGY; NUTRITION & DIETETICS; PUBLIC HEALTH