Epidemiology of Developmental Dysplasia of the Hip: Analysis of Japanese National Database.

BACKGROUND: Developmental dysplasia of the hip (DDH) is a cluster of hip development disorders that affects infants. The incidence of DDH-related dislocation (DDH-dislocation) is reportedly 0.1-0.3%; however, the nationwide incidence of DDH-dislocation in Japan has not been previously reported. The primary aim of this study was to report the nationwide incidence of DDH-dislocation in Japan using the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB), and to examine its regional variation across Japan. METHODS: This was a retrospective birth cohort study using the NDB. Data on patients born between 2011 and 2013 and assigned DDH-dislocation-related disease codes during 2011-2018 were extracted. Among these, patients who underwent treatment for DDH-dislocation between 2011 and 2018 were defined as patients with DDH-dislocation. RESULTS: Across the 2011, 2012, and 2013 birth cohorts, 2,367 patients were diagnosed with DDH-dislocation, yielding the nationwide incidence of 0.076%. Region-specific incidence rates were almost similar across Japan. Secondary analyses revealed that 273 (11.5%) patients were diagnosed at the age of ≥1 year. The effect of birth during the cold months on the incidence of DDH-dislocation was significant (relative risk [RR] = 1.89, 95% confidence interval [CI]: 1.75-2.06). The risk of DDH-dislocation among girls was approximately seven times higher than that among boys. CONCLUSION: This is the first study to report the nationwide incidence of DDH-dislocation in Japan, which was estimated at 0.076%. The regional variation was trivial and unlikely to be clinically significant. Thus, the incidence rates were approximately equal across all regions in Japan.

Mathematical model estimation of dengue fever transmission risk from Southeast and South Asia into Japan between 2016 and 2018.

BACKGROUND: Dengue fever is a viral infection transmitted to humans through the bite of a mosquito infected with the dengue virus. Dengue is one of the most common infectious diseases in the world, and its incidence is rapidly increasing. We estimated the risk of dengue importation from endemic countries to Japan and the transmission risk within Japan using data collected between 2016 and 2018. METHODS: We conducted simulations that included the number of reported dengue infections and travelers per month in ten countries in Southeast and South Asia. RESULTS: The estimated importation risks for Japanese returnees and international travelers from each of the ten endemic countries was approximately 1.0 every month from 2016 to 2018. The autochthonous transmission risk in Japan from any target country was 1.0 from June to September yearly. The estimated number of Japanese dengue cases returning to Japan is approximately 25 times higher than that of imported cases reported in Japan. CONCLUSIONS: The risk of dengue importation into Japan can be sufficiently high. Attention should be paid to autochthonous transmission spread between June and September when mosquitoes are active in Japan. Estimates of seasonal risk variation from each dengue virus-endemic country can be used to inform preventive and control measures for dengue in Japan.

Experience using donor human milk: A single-center cohort study in Japan.

BACKGROUND: Donor human milk (DHM) became available in Japan when the first human milk bank was established in 2017. This study investigated the effects of DHM on enteral nutrition (EN) in very low birth weight (VLBW) infants in the single center in Japan. METHODS: Seventy-six VLBW infants hospitalized between April 2017 and March 2020 at Showa University Hospital were included in the study. We retrospectively evaluated age (hours) at which EN was initiated and age (days) until complete feeding (EN > 100 mL/kg/day) was achieved. We compared the DHM and non-DHM groups, or the early human milk (EHM) and non-EHM groups. The EHM group was defined as those in which EN was initiated with the mother's own milk or DHM within 12 h of birth. RESULTS: In 30 extremely low birth weight (ELBW) infants, EN was initiated at significantly earlier postnatal hours in the DHM group compared to those in the non-DHM group. Complete feeding was achieved at significantly earlier ages in the EHM group after adjusting for gastrointestinal complications and gestational age. Additionally, the changes in body weight z-scores from birth to term-equivalent age were significantly greater in the EHM group after adjusting for exclusive breastfeeding and small for gestational age, compared to the non-EHM group. Statistical significance was not noted in 46 subjects (birth weight, 1000-1500 g). CONCLUSION: The use of DHM may contribute to earlier initiation and achievement of EN, resulting in greater early postnatal growth in ELBW infants in Japan.

Predictors of resignation and sick leave after cancer diagnosis among Japanese breast cancer survivors: a cross-sectional study.

BACKGROUND: In Japan, 55.5% of breast cancer survivors (BCSs) are of working age, so various perspectives regarding return to work (RTW) after cancer diagnosis need to be considered. Therefore, this study aimed to clarify the risk factors for resignation and taking sick leave (SL) among BCSs in continued employment at the time of diagnosis. METHODS: A web-based retrospective cross-sectional survey was conducted on BCSs using data from a 2018 Japanese national research project (Endo-Han) commissioned by the Ministry of Health, Labour and Welfare of Japan. The subjects were women aged 18-69 years who had been diagnosed with breast cancer for the first time at least 1 year previously. The risk factors for resignation and taking SL after breast cancer diagnosis, including age at diagnosis, education level, cancer stage, surgery, chemotherapy, radiotherapy, employment status, and occupational type, were then analyzed using a logistic regression model. RESULTS: In total, 40 (14.9%) of 269 BCSs quit their jobs at least 1 year after being diagnosed with breast cancer. The results of the multivariable analysis indicated that lower education level (odds ratio [OR]: 3.802; 95% confidence interval [CI]: 1.233-11.729), taking SL (OR: 2.514; 95%CI: 1.202-5.261), and younger age at diagnosis (OR: 0.470; 95%CI: 0.221-0.998) were predictors of resignation. Of 229 patients who continued working, SL was taken by 72 (31.4%). In addition, undergoing surgery was found to be a predictor of taking SL (OR: 8.311; 95%CI: 1.007-68.621). CONCLUSIONS: In total, 40 (14.9%) of 269 BCSs quit their jobs at least 1 year after being diagnosed with breast cancer. The results of this study indicated that younger age, lower education level, and taking SL were predictors of resignation after breast cancer diagnosis.

Eating Fast and Until Full Is Associated with Elevated Alanine Aminotransferase Activity in Japanese Schoolchildren: A Cross-Sectional Study.

Alanine aminotransferase (ALT) activity has been recognized as a marker for monitoring the risk of metabolic syndrome, diabetes and non-alcoholic fatty liver disease in children. Higher ALT activity was reported to be associated with eating fast in Japanese adults, but the association in children is unclear. Moreover, eating fast and eating until full are reported to be associated with being overweight. This study examined the association between elevated ALT and eating behaviors (eating fast and eating until full) among population-based schoolchildren (aged 9-10 years) in Ina Town, Saitama, Japan. Data for eating behaviors were obtained from a self-written questionnaire. Blood samples were drawn to measure ALT. Elevated ALT was defined as > 30 U/L in boys and > 19 U/L in girls. Logistic regression models and structural equation models were used to calculate the effect of eating behaviors on elevated ALT. Final data analysis was carried out for 1,870 boys and 1,739 girls. "Eating fast and eating until full" was significantly associated with elevated ALT in each sex. "Eating fast and not eating until full" was significantly associated with elevated ALT in boys, but after adjusting for exercise and body mass index, this association was not significant. In conclusion, "eating fast and eating until full" was associated with elevated ALT in schoolchildren. A sex difference in the association of "eating fast and not eating until full" with elevated ALT was observed. Modifying the behaviors of eating fast and eating until full is important for schoolchildren to prevent ALT elevation.

Correction to: Cross-sectional study of associations between normal body weight with central obesity and hyperuricemia in Japan.

After publication of this article [1], it was brought to our attention that there is an error in the Table 5, which "Cases" should be revised to "HU" in Table 5. The original publication has been corrected.

Cross-sectional study of associations between normal body weight with central obesity and hyperuricemia in Japan.

BACKGROUND: Several studies have shown that normal weight with central obesity (NWCO) is associated with cardiovascular disease risk factors such as hypertension, dyslipidemia and diabetes. However, the relationship between NWCO and hyperuricemia has not been studied in detail. METHODS: We investigated the association between NWCO and hyperuricemia among Japanese adults aged 40-64 years who had undergone periodic health examinations between April 2013 and March 2014. Obesity was defined as a body mass index (BMI) ≥25 kg/m2 and central obesity was determined as a waist-to-height ratio (WHtR) ≥0.5. We classified the participants into the following groups based according to having obesity and central obesity: normal weight (BMI 18.5-24.9 kg/m2) without (NW; WHtR < 0.5) and with (NWCO) central obesity, and obesity without (OB) and with (OBCO) central obesity. Hyperuricemia was defined as serum uric acid > 7.0 and ≥ 6.0 mg/dL in men and women, respectively, or under medical treatment for hyperuricemia. Alcohol intake was classified as yes (daily and occasional consumption) and none (no alcohol consumption). Odds ratios (OR) and 95% confidence intervals (CI) for hyperuricemia were calculated using a logistic regression model. RESULTS: We analyzed data derived from 96,863 participants (69,241 men and 27,622 women). The prevalences of hyperuricemia in men and women were respectively, 21.4 and 11.0%, and of participants with NWCO respectively 15.6 and 30.0%. The adjusted OR for hyperuricemia was significantly increased in OBCO compared with NW, regardless of sex (men: OR, 2.12; 95%CI; 2.03-2.21; women: OR, 3.54; 95%CI, 3.21-3.90) and were statistically significant in NWCO compared with NW (men: OR, 1.44; 95%CI, 1.36-1.52; women: OR, 1.41; 95%CI, 1.27-1.57). The results were similar regardless of alcohol consumption. CONCLUSIONS: We found that NWCO and OBCO were associated with hyperuricemia in middle-aged Japanese men and women. Middle-aged Japanese adults with normal weight but having central obesity should be screened using a combination of BMI and WHtR and educated about how to prevent hyperuricemia.

Elevated alanine aminotransferase and low aspartate aminotransferase/alanine aminotransferase ratio are associated with chronic kidney disease among middle-aged women: a cross-sectional study.

BACKGROUND: Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) to ALT ratio (AST/ALT ratio) have been shown to be related to non-alcoholic fatty liver disease or insulin resistance, which was associated with chronic kidney disease (CKD). However, it is unclear whether ALT and AST/ALT ratio are associated with CKD. In this study, we examined the relationship of ALT and AST/ALT ratio to CKD among middle-aged females in Japan. METHODS: The present study included 29,133 women aged 40 to 64 years who had an annual health checkup in Japan during April 2013 to March 2014. Venous blood samples were collected to measure ALT, AST, gamma-glutamyltransferase (GGT), and creatinine levels. In accordance with previous studies, ALT > 40 U/L and GGT > 50 U/L were determined as elevated, AST/ALT ratio < 1 was regarded as low, and CKD was defined as estimated glomerular filtration rate < 60 mL/min/1.73 m2 and/or proteinuria. Logistic regression model was used to calculate the odds ratio (OR) and 95% confidence interval (CI) for CKD. RESULTS: "Elevated ALT and elevated GGT" and "elevated ALT and non-elevated GGT" significantly increased the OR for CKD when compared with "non-elevated ALT and non-elevated GGT" (OR: 2.56, 95% CI: 2.10-3.12 and OR: 2.24, 95% CI: 1.81-2.77). Compared with "AST/ALT ratio ≥ 1 and non-elevated GGT", "AST/ALT ratio < 1 and elevated GGT" and "AST/ALT ratio < 1 and non-elevated GGT" significantly increased the OR for CKD (OR: 2.73, 95% CI: 2.36-3.15 and OR: 1.68, 95% CI: 1.52-1.87). These findings still remained after adjustment for confounders. CONCLUSIONS: Elevated ALT was associated with CKD regardless of GGT elevation. Moreover, low AST/ALT ratio was also associated with CKD independent of GGT elevation.

Changes in overweight/obesity and central obesity status from preadolescence to adolescence: a longitudinal study among schoolchildren in Japan.

BACKGROUND: Little is known about changes in overweight/obesity and central obesity status among schoolchildren from preadolescence to adolescence in Japan, where waist circumference (WC) is generally not measured in annual health examinations at elementary and junior high schools. This study examined changes of overweight/obesity and central obesity status among schoolboys and schoolgirls from preadolescence to adolescence in Japan. METHODS: Study subjects were fourth-grade school children (9 or 10 years of age) from all four of Ina town's elementary schools in Japan. Measurement of each participant's height, weight, and WC were made at baseline and 3 years later. Childhood overweight/obesity was determined according to the age- and sex-specific body mass index cut-off points proposed by the International Obesity Task Force. Central obesity was defined as waist-to-height ratio ≥ 0.5. Kappa (κ) statistic was calculated to examine the tracking of overweight/obesity and central obesity. RESULTS: Data from 1436 participants (boys: n = 720, girls: n = 716) were analyzed. Overweight/obesity status tracked substantially from fourth grade to seventh grade in both boys (κ = 0.614, P value < 0.001) and girls (κ = 0.619, P value < 0.001). Among participants who were overweight/obese in fourth grade, 55.2% of boys and 63.2% of girls were still overweight/obese in seventh grade. Tracking of central obesity from fourth graders to seventh graders was substantial in boys (κ = 0.651, P value < 0.001) and moderate in girls (κ = 0.544, P value < 0.001). Among participants who had central obesity in fourth grade, 54.1% of boys and 52.6% of girls still had central obesity in seventh grade. CONCLUSIONS: The present study showed that the tracking of overweight/obesity from preadolescence to adolescence was substantial in boys and girls. Moreover, more than half of those who had central obesity in preadolescence had central obesity in adolescence. This study suggests that it is important to implement a primary prevention program for overweight/obesity and central obesity in elementary schools before fourth grade.

Survey of a nutrition management method for very low birthweight infants: Status before wide use of breast milk banks in Japan.

BACKGROUND: The importance of breast-feeding for very low birthweight (VLBW) infants has been pointed out. Some overseas studies suggested that the standardization of enteral nutrition (EN) leads to improved prognosis in VLBW infants. In Japan, however, physicians in charge of infants are responsible for making nutrition management decisions on an individual basis. We conducted an online survey to clarify the course of nutrition management of VLBW infants currently implemented in Japan. METHODS: We mailed a notice to 300 representative neonatologists throughout Japan requesting their participation in the online survey. On the survey website, neonatologists responded to questions regarding the nutritional strategy for five birthweight groups (less than 500 g, 500-749 g, 750-999 g, 1,000-1,249 g and 1,250-1,499 g). RESULTS: Responses were recieved from 137 neonatologists. The first choice for EN up to 1 week after birth was breast milk regardless of birthweight (92.0% for 1,250-1,499 g to 95.6% for 500-999 g). More than 30% of the respondents answered that they fast infants who weigh <750 g at birth or feed them with other mothers' breast milk until their own mother's milk becomes available. The lower the birthweight, the later EN is started, and the greater the number of days to establish EN. CONCLUSION: The lower the birthweight, the more difficult it is to feed infants their own mother's milk and the later the EN is started. If donor milk is supplied in a stable manner, it takes fewer days to establish EN.

Prognostic Value of Left Atrial Size and Functional Indices Measured by 3-Dimensional Speckle-Tracking Analysis.

BACKGROUND: The prognostic value of indices for left atrial volumes (LAV) and reservoir function measured by 3D speckle-tracking analysis (3DSTA) has not been determined. Methods and Results: LA maximal and minimal volume indices (LAVImax, LAVImin), and LA emptying fraction (LAEmpF) were measured via 2D echocardiography (2DE) and 3DSTA in 514 patients (62% male, mean age: 66±15 years) with various cardiovascular diseases. Two cutoff values using normal±2SD (cutoff criterion 1) and receiver-operating characteristic analysis (cutoff criterion 2) were evaluated. During a mean follow-up of 720±383 days, MACE (cardiac death, nonfatal myocardial infarction, stroke and admission for heart failure) occurred in 98 patients. Kaplan-Meier survival analysis showed both cutoff criteria measured by 2DE and 3DSTA had significant predictive power for MACE (P<0.001). For cutoff criterion 1, 3DSTA measurements yielded higher hazard ratios than 2DE by Cox proportional hazard model. Cutoff criterion 2 using 3DSTA had higher average treatment effect values than 2DE by matching propensity scores on the outcome. Further, a regression model that included clinical variables, left ventricular ejection fraction and cutoff criterion 2 using 3DSTA-derived LAEmpF had significantly higher prognostic power than 2DE. CONCLUSIONS: LA indices measured by 3DSTA had greater prognostic power for future MACE than 2DE. In particular, 3DSTA-derived LAEmpF has the potential to be a valuable prognostic tool in clinical settings.

Association between serum lipids and low back pain among a middle-aged Japanese population: a large-scale cross-sectional study.

BACKGROUND: Abnormal lipid levels have been suggested as a mechanism leading to atherosclerosis of the lumbar vessels, resulting in low back pain (LBP). This study examined whether abnormal lipid levels were associated with LBP among middle-aged adults in Japan. METHODS: The present study included adults between 40 and 64 years old who underwent an annual health checkup. A total of 258,367 eligible participants were analyzed to investigate associations of LBP with low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and LDL-C/HDL-C ratio. Participants were categorized into two groups according to each of LDL-C, HDL-C, and LDL-C/HDL-C ratio (LDL-C: ≥ 140 vs. < 140 mg/dL; HDL-C: ≥ 40 vs. < 40 mg/dL; LDL-C/HDL-C ratio: ≥ 2.5 vs. < 2.5). Information on LBP was obtained using a self-administered questionnaire. Logistic regression modeling was used to calculate the odds ratio (OR) and 95% confidence interval (CI) for LBP. RESULTS: The prevalence of LBP was 2.2% in men and 2.1% in women. Multivariable analysis adjusting for age, body mass index, and lifestyle factors found significant associations for HDL-C <  40 mg/dL (OR, 1.34; 95%CI, 1.20-1.48 in men; OR, 1.32; 95%CI, 1.02-1.72 in women) and LDL-C/HDL-C ratio ≥ 2.5 (OR, 1.17; 95%CI, 1.09-1.26 in men; OR, 1.15; 95%CI, 1.03-1.29 in women) with LBP. CONCLUSIONS: Low HDL-C and high LDL-C/HDL-C ratio were significantly associated with LBP in a middle-aged Japanese population. These findings might support the atherosclerosis-LBP hypothesis.

Effects of eating dinner alone on overweight in Japanese adolescents: a cross-sectional survey.

BACKGROUND: The decrease in the frequency of family meals among Asian youth is often lamented. In Japan, adolescents who eat breakfast alone might have an unhealthy diet, which increases the risk of overweight or obese. However, there are few studies on the relationship between eating dinner alone and overweight in Japanese adolescents. Here, we investigated if eating dinner alone is associated with being overweight in Japanese adolescents of each sex. METHODS: The participants consisted of 890 seventh graders (12-13 years of age) from the junior high schools of Ina, Japan who were recruited from 2011 to 2012. Information about eating dinner alone was obtained using a self-reported questionnaire, which was given to each participant. The participants were classified into the following three groups: does not eat alone, eats alone 1-2 times/week, or eats alone ≥3 times/week. A logistic regression model was used to examine the relationship between eating dinner alone and being overweight. The height and weight of each participant were measured. Childhood overweight status was defined using the body mass index cutoff points proposed by the International Obesity Task Force. RESULTS: When compared with girls who did not eat dinner alone, a significantly increased odds ratio (OR) was observed among girls who ate dinner alone ≥1 time/week (adjusted OR = 2.78; 95% confidence interval = 1.21-6.38). In contrast, there was no statistically significant difference between eating dinner alone and being overweight among boys. CONCLUSION: The present study found that eating dinner alone is associated with being overweight among adolescent girls in this community in Japan. Therefore, reducing the frequency of eating dinner alone might contribute to decreasing the risk for becoming overweight or obese among adolescent girls.

Relationship between Eating Quickly and Overweight : A Cohort Study of Schoolchildren in Japan.

Several cross-sectional studies have shown that eating quickly is associated with overweight in children and adolescents. However, few cohort studies have examined this relationship. Here we investigated the relationship between eating quickly and overweight in a cohort study of fourth-grade schoolchildren (aged 9 or 10 years) who attended elementary schools in Ina-town, Japan. The children were followed for 3 years from 2001-2004 (at baseline) to 2004-2007. A questionnaire survey including information about eating speed (fast, medium, or slow) was administered, and height and weight measurements were obtained at baseline and follow-up. Overweight was defined according to the body mass index cutoff points proposed by the International Obesity Task Force. We used a Poisson regression model to examine the association between eating quickly at baseline and being overweight 3 years later. Data from 934 non-overweight children (465 boys, 469 girls) were analyzed. Eating quickly was not significantly associated with being overweight in the boys, whereas it was significantly associated with being overweight in the girls. Our analysis indicates that among girls, eating quickly leads to overweight, and that the modification of eating quickly could help prevent overweight in adolescents.

Trends of Underweight and Overweight/Obesity Among Japanese Schoolchildren From 2003 to 2012, Defined by Body Mass Index and Percentage Overweight Cutoffs.

BACKGROUND: We investigated the prevalence and trends of underweight and overweight/obesity in a population-based sample of Japanese schoolchildren from 2003 to 2012, defined by body mass index (BMI) and percentage overweight (POW). METHODS: Subjects comprised fourth and seventh graders from the town of Ina, Japan, from 2003 to 2012. The height and weight of each subject were measured. Children were classified as underweight, normal weight, or overweight/obese using two criteria: BMI cutoff points proposed by the International Obesity Task Force and cutoffs based on POW in Japan. RESULTS: Data from 4367 fourth graders and 3724 seventh graders were analyzed. The prevalence of underweight and overweight as defined by POW criteria were lower than those based on BMI criteria. There was a decrease in the prevalence of overweight among fourth-grade boys and girls and seventh-grade girls according to BMI; this decrease was also observed when POW criteria were used for the definition of overweight. CONCLUSIONS: The prevalence and trends of both underweight and overweight as defined by POW were underestimated among Japanese schoolchildren compared to those determined using BMI. The results of this study also suggest that trends in underweight and overweight/obesity using POW criteria are similar to those based on BMI criteria among schoolchildren in Japan.

Dietary patterns and serum gamma-glutamyl transferase in Japanese men and women.

BACKGROUND: Although specific foods and nutrients have been examined as potential determinants of serum gamma-glutamyl transferase (GGT) concentrations, the relationship between dietary patterns and GGT remains unknown. The present cross-sectional study aimed to determine relationships between dietary patterns and GGT concentrations, and the effects of lifestyle factors on GGT. METHODS: Relationships between dietary patterns and GGT were analyzed in 9803 Japanese individuals (3723 men and 6080 women age 40-69 years) without a history of liver diseases or elevated serum aminotransferase. We examined major dietary patterns by factor analysis of 46 items determined from a validated, short food frequency questionnaire. RESULTS: We defined dietary patterns as healthy, Western, seafood, bread, and dessert. The healthy pattern was inversely related to GGT in men (odds ratio [OR] for highest vs lowest quartile, 0.72; 95% confidence interval [CI], 0.57-0.92; P < 0.01 for trend) and women (OR 0.82; 95% CI, 0.66-1.0; P = 0.05 for trend), whereas the seafood pattern was positively related to GGT in men (OR 1.27; 95% CI, 1.01-1.61; P = 0.03 for trend) and women (OR 1.21; 95% CI, 0.98-1.49; P = 0.05 for trend). Male-specific inverse associations with GGT were found for bread and dessert patterns (OR 0.63; 95% CI, 0.50-0.80 and OR 0.53; 95% CI, 0.41-0.68, respectively; P < 0.01 for both trends). Seafood or bread patterns and alcohol consumption significantly interacted with GGT in men (P = 0.03 and <0.01 for interaction, respectively) and between the dessert pattern and body mass index or smoking habit in women (P = 0.03 and <0.01, respectively, for interaction). CONCLUSIONS: Dietary patterns may be important determinants of GGT, and their possible clinical implications warrant further investigation.

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.

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.

The impact of eating quickly on anthropometric variables among schoolgirls: a prospective cohort study in Japan.

BACKGROUND: Because most studies about the relationship between eating quickly and overweight/obesity have been cross-sectional, it is necessary to investigate prospectively the influence of eating quickly on anthropometric variables in order to examine the causal relationship. The aim of the present study was to investigate the impact of eating quickly on anthropometric variables among schoolgirls in a prospective cohort study. METHODS: We investigated 427 non-overweight/obese schoolgirls from fourth grade (aged 9 or 10 years) in Ina-town, Japan from 2004 to 2006. Physical examinations and a questionnaire survey were conducted in fourth grade and 3 years later (in seventh grade). Height, weight, percent body fat (%BF) and waist circumference (WC) were measured in physical examinations, and information on eating speed was collected in a questionnaire survey. RESULTS: The differences in anthropometric variables (body mass index, %BF, WC and waist-to-height ratio) between fourth and seventh grade were significantly greater in girls who continued to eat quickly from fourth to seventh grade than in those who did not continue to eat quickly during this 3-year period. In contrast, these differences were not statistically significant in girls who ate quickly in fourth grade but not in seventh grade compared with those who did not continue to eat quickly during the 3-year period. CONCLUSION: Eating quickly was associated with excess gains in anthropometric variables. The present study also suggested that stopping a habit of eating quickly prevents these excess gains in non-overweight/obese girls, which could contribute to the prevention of childhood overweight and obesity.

Abdominal obesity and serum adiponectin complexes among population-based elementary school children in Japan: a cross-sectional study.

BACKGROUND: There are a limited number of studies regarding the association between abdominal obesity and serum adiponectin complexes (high, medium, and low molecular weight adiponectins) among population-based elementary school children, especially in Japan, where blood collection is not usually performed during annual health examinations of school children. The aim of the present study was to investigate the relationship between abdominal obesity and serum adiponectin complexes among population-based elementary school children in Japan. METHODS: Subjects were all the fourth-grade school children (9 or 10 years of age) in the town of Ina during 2005-2008 (N = 1675). The height, weight, percent body fat, and waist circumference (WC) of each subject were measured. Blood samples were drawn from subjects to measure adiponectin isoform values. Childhood abdominal obesity was defined as "a waist-to-height ratio greater than or equal to 0.5" or "a WC greater than or equal to 75 cm". The Wilcoxon rank-sum test and the logistic regression model were used to analyze the association between abdominal obesity and each adiponectin isoform value. RESULTS: Data from 1654 subjects (846 boys and 808 girls) were analyzed. Adiponectin complexes were lower in the abdominal obesity group than in the non-abdominal obesity group regardless of sex. Abdominal obesity significantly increased the odds ratio (OR) for each adiponectin isoform level less than or equal to the median value in boys; the OR (95% confidence interval [CI]) was 2.50 (1.59-3.92) for high molecular weight adiponectin (HMW-adn), 2.47 (1.57-3.88) for medium molecular weight adiponectin (MMW-adn), and 1.75 (1.13-2.70) for low molecular weight adiponectin (LMW-adn). In girls, the OR (95% CI) was 1.95 (1.18-3.21) for HMW-adn, 1.40 (0.86-2.28) for MMW-adn, and 1.06 (0.65-1.70) for LMW-adn. CONCLUSIONS: Abdominal obesity was associated with lower adiponectin complexes and the influence of abdominal obesity varied by adiponectin isoform. Furthermore, the impact of abdominal obesity was larger in boys than in girls. The present study results suggest that prevention of abdominal obesity could contribute to the prevention of lower adiponectin levels, especially in boys.

Association of blood pressure and body mass index with intraocular pressure in middle-aged and older Japanese residents: a cross-sectional and longitudinal study.

To clarify whether high blood pressure (BP) and high body mass index (BMI) are associated with elevated intraocular pressure (IOP), a cross-sectional and longitudinal study was conducted. This epidemiological study analyzed health examination data obtained between 2001 and 2005 from 896 Japanese individuals (aged 32-79 years) who had not undergone any ocular surgery or medical treatment for hypertension, ocular hypertension, or glaucoma. Multiple-regression analysis of our cross-sectional data showed that systolic and diastolic BP (SBP and DBP) and BMI had significant and near-significant positive associations with IOP in men (p＜0.05) and women (p＜0.1). Our longitudinal study from analyses of covariance found that the adjusted mean level of changes in IOP tended to increase with increased levels of SBP, DBP, and BMI in men (p＜0.1). In women also, changes in SBP and BMI tended to be positively related with that of IOP (p＜0.1). The results of this study suggested that BP and BMI were positively associated with IOP in middle-aged and older Japanese. Therefore, management of BP and improvement of obesity might be especially important to Japanese patients with open-angle glaucoma or ocular hypertension as they have a higher incidence of normal-tension glaucoma than Europeans and Americans.