title: Waist-to-height ratio is more closely associated with alanine aminotransferase levels than body mass index and waist circumference among population-based children: a cross-sectional study in Japan.
abstract: BACKGROUND
  An association between anthropometric measurements, including waist circumference (WC), and alanine aminotransferase (ALT) levels has been reported among adults. However, studies conducted among population-based elementary schoolchildren to date have been limited, especially in Japan, where the measurement of WC and blood collection are not usually performed in the annual health examination at elementary schools. The present study investigated the association between anthropometric measurements and ALT levels among population-based elementary schoolchildren in Japan.
  
  
  METHODS
  Subjects were fourth-grade schoolchildren (aged 9 or 10) from the town of Ina in Saitama Prefecture, Japan during 2004-2009. The height, weight, and WC of each subject were measured, and blood samples were drawn to measure ALT levels. Childhood overweight or obesity was defined according to the age- and sex-specific cut-off points proposed by the International Obesity Task Force. Spearman's correlation coefficients between anthropometric measurements (body mass index (BMI), WC, and waist-to-height ratio (WHtR)) and ALT levels were calculated.
  
  
  RESULTS
  Data from 2499 subjects (1293 boys and 1206 girls) were analyzed. BMI, WC, and WHtR were significantly positively correlated with ALT levels; the correlation coefficient of ALT levels with WHtR was higher than that with BMI and WC in boys and girls. In the analysis stratified by physique (non-overweight/obesity, overweight, or obesity), all anthropometric measurements were significantly positively correlated with ALT levels among boys, while only WHtR was significantly positively correlated with ALT levels among girls. Moreover, the correlation coefficient of ALT levels with WHtR was more pronounced than that with BMI and WC in the non-overweight/obesity group, in the overweight group, and in the obesity group for each sex.
  
  
  CONCLUSIONS
  The present study showed that WHtR was more closely associated with ALT levels than BMI and WC. Furthermore, only WHtR was significantly positively associated with ALT levels regardless of sex and physique. This study suggests that it is more useful to monitor WHtR than BMI and WC as a surrogate for ALT levels among population-based elementary schoolchildren.
authors.affiliation: Department of Public Health, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan. h-ochiai@med.showa-u.ac.jp.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Ochiai
authors.affiliation: Department of Public Health, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan. shirasawa@med.showa-u.ac.jp.
authors.forename: Takako
authors.initials: T
authors.lastname: Shirasawa
authors.affiliation: Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan. rimei@jikei.ac.jp.
authors.forename: Rimei
authors.initials: R
authors.lastname: Nishimura
authors.affiliation: Department of Public Health, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan. nanrih@med.showa-u.ac.jp.
authors.forename: Hinako
authors.initials: H
authors.lastname: Nanri
authors.affiliation: Department of Public Health, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan. tohtsu@med.showa-u.ac.jp.
authors.forename: Tadahiro
authors.initials: T
authors.lastname: Ohtsu
authors.affiliation: Department of Public Health, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan. hhiromi@med.showa-u.ac.jp.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Hoshino
authors.affiliation: Jikei University School of Medicine, Tokyo, Japan. ntajima@jikei.ac.jp.
authors.forename: Naoko
authors.initials: N
authors.lastname: Tajima
authors.affiliation: Department of Public Health, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan. akokaze@med.showa-u.ac.jp.
authors.forename: Akatsuki
authors.initials: A
authors.lastname: Kokaze
mesh_terms: D000410:Alanine Transaminase / Q000097:blood*; D001827:Body Height; D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D009765:Obesity / Q000201:enzymology / Q000453:epidemiology; D050177:Overweight / Q000201:enzymology / Q000453:epidemiology; D012737:Sex Factors; D055105:Waist Circumference
chemical_list: D000410:Alanine Transaminase