Eating quickly is associated with waist-to-height ratio among Japanese adolescents: a cross-sectional survey

Background

Central obesity, based on waist circumference (WC), has more adverse effects on health than general obesity, determined by body mass index. To date, eating quickly has been reported to be risk factors for overweight/obesity among children, adolescents, and adults. In contrast, there are few studies on the relationship between fast eating and central obesity among adolescents, particularly in Japan, where WC is not commonly measured in junior high schools. The aim of the present study was to investigate the relationship between eating quickly and waist-to-height ratio (WHtR), an index of central obesity, among adolescents in Japan.

Methods

Study subjects were 2136 seventh-grade school children (12 or 13 years of age) from Ina town junior high schools in Japan, between 2004 and 2009. Measurements of height, weight, and WC were performed, and information about eating habits was collected using a self-administered questionnaire. A logistic regression model was used to calculate the odds ratio (OR) and 95 % confidence interval (95 % CI) for WHtR ≥ 0.5.

Results

Eating quickly significantly increased the OR for WHtR ≥ 0.5 in boys (OR: 2.05, 95 % CI: 1.31–3.23) and girls (2.09, 1.15–3.81). When compared with the “not eating quickly and not eating until full” group, the OR for WHtR ≥ 0.5 in the “eating quickly and eating until full” group was 2.67 (95 % CI: 1.50–4.73) in boys and 2.59 (1.17–5.73) in girls, whereas that in the “eating quickly and not eating until full” group or the “not eating quickly and eating until full” group was not statistically significant regardless of sex.

Conclusions

The present study showed that eating quickly was associated with WHtR ≥ 0.5, and “eating quickly and eating until full” had a substantial impact on WHtR ≥ 0.5 among adolescents. This study suggests that modifying fast eating to a slower pace may help prevent central obesity among adolescents.

Rapid weight gain during early childhood is associated with overweight in preadolescence: a longitudinal study in Japan

BACKGROUND

The objective of this study was to examine the relationship between rapid weight gain during early childhood and overweight in preadolescence by sex.

METHOD

Study subjects were 676 boys and 620 girls in fourth grade (aged 9 or 10 years) from elementary schools in Ina-town, Japan, during 2010-2012. Height and weight of subjects at birth, age 1.5 and 3 years, were collected from the Maternal and Child Health Handbook, while values at 9-10 years were measured. Rapid weight gain was defined as a change in weight-for-age standard deviation score greater than 0.67 from birth to age 1.5 years (0-1.5 years) or from age 1.5 to 3 years (1.5-3 years).

RESULTS

After adjustment for confounding factors, compared with no rapid weight gain, rapid weight gain during 0-1.5 years and 1.5-3 years or rapid weight gain during 1.5-3 years but not during 0-1.5 years significantly increased the odds ratio (OR) for overweight at age 9-10 years in boys (OR, 6.21; 95% confidence interval [CI], 2.84-13.58 and OR, 3.31; 95% CI, 1.67-6.54, respectively) and girls (OR, 7.55; 95% CI, 2.99-19.07 and OR, 3.42; 95% CI, 1.38-8.49, respectively).

CONCLUSION

The present study suggests that rapid weight gain during early childhood was associated with being overweight in preadolescence, regardless of sex.

Mental health status among Japanese medical students: a cross-sectional survey of 20 universities

The purposes of this study were to evaluate the mental health status of Japanese medical students and to examine differences based on gender, as well as on university type and location, using the results of a nationwide survey. Between December 2006 and March 2007, we conducted a questionnaire survey among fourth-year medical students at 20 randomly selected medical schools in Japan. The data from 1,619 students (response rate: 90.6%; male: 1,074; female: 545) were analyzed. We used the Japanese version of the 12-item General Health Questionnaire (GHQ-12) to measure mental health status. Poor mental health status (GHQ-12 score of 4 points or higher) was observed in 36.6% and 48.8% of the male and female medical students, respectively. The ratio of the age-adjusted prevalence of poor mental health status in female versus male medical students was 1.33 (95% confidence interval: 1.10-1.62). The universities were categorized into two groups based on the university type (national/public: 15 vs. private: 5) or location (in a large city: 7 vs. in a local city: 13 cities). The prevalence of poor mental health status in both men and women differed between these groups, although not significantly. The GHQ-12 scores in men significantly differed between the categorized groups of universities. These results suggest that adequate attention must be paid to the mental health of medical students, especially females, and that a system for providing mental health care for medical students must be established in the context of actual conditions at each university.

The relationship between distorted body image and lifestyle among Japanese adolescents: a population-based study

Background

Distorted body image plays a significant role in the development of obesity, eating problems, and eating disorders. The aim of this study was to investigate the relationship between distorted body image and lifestyle among Japanese adolescent boys and girls.

Methods

Subjects were 1731 seventh graders (age 12–13 years) from the Ina-town’s junior high schools, Japan, from 2005–2009. The height and weight of each subject were measured. Childhood underweight, overweight, and obesity were defined using the body mass index cutoff points proposed by the International Obesity Task Force. Information regarding the self-perceived weight status and lifestyles (exercise, snacking after dinner, breakfast, wakeup time, bedtime) of each subject was collected using a self-administered questionnaire. Self-perceived weight status was categorized into three groups (thin, normal, or heavy), and compared with the subjects’ actual weight status. Body image perception was categorized into the following three groups: an underestimated own weight status group (underestimated group), a correct own weight status group (correct group) and an overestimated own weight status group (overestimated group).

Results

The proportion of boys in the underestimated group was higher than that of girls, while the opposite was true for the overestimated group (P < 0.001). There were no statistically significant differences in lifestyle between the underestimated group and the correct group regardless of sex. In contrast, there were statistically significant differences between the overestimated group and the correct group in the lifestyle factors of exercise among boys and snacking after dinner among girls. The adjusted odds ratio (OR) in boys who exercised daily significantly decreased (OR: 0.35, 95 % CI: 0.16–0.77), while a significantly increased OR was observed in girls who snacked after dinner (OR: 1.53, 95 % CI: 1.07–2.19).

Conclusion

Adolescent boys tended to underestimate their body weight, whereas adolescent girls were likely to overestimate their body weight. Furthermore, lifestyle factors associated with distorted body image differed by sex, with exercise affecting body image perception among boys and snacking after dinner affecting body image perception among girls. Thus, lifestyle may lead to distorted body image among adolescents.

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.

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.

Longevity-associated mitochondrial DNA 5178 C/A polymorphism modulates the effects of coffee consumption on erythrocytic parameters in Japanese men: an exploratory cross-sectional analysis

Background

Mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism reportedly modulates the effects of coffee consumption on the risk of hypertension, dyslipidemia and abnormal glucose tolerance. The objective of this analysis was to investigate whether Mt5178 C/A polymorphism modifies the effects of coffee consumption on erythrocytic parameters in male Japanese health check-up examinees.

Methods

A total of 436 men (mean age ± standard deviation, 54.1 ± 7.8 years) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, an exploratory cross-sectional analysis assessing the joint effects of Mt5178 C/A polymorphism and coffee consumption on red blood cell counts, hematocrit and hemoglobin was conducted.

Results

For Mt5178C genotypic men, after adjustment for age, body mass index, alcohol consumption, habitual smoking and green tea consumption, coffee consumption significantly decreased red blood cell counts (P for trend = 0.022) and hemoglobin (P for trend = 0.035). The risk of anemia, defined as hemoglobin of <14 g/dL, after the aforementioned adjustment, appeared to depend on coffee consumption (P for trend = 0.078), and the adjusted odds ratio for anemia was significantly higher in men who consumed ≥4 cups of coffee per day than in those who consumed <1 cup per day (odds ratio = 3.771, 95% confidence interval: 1.088 to 13.06, P = 0.036). For Mt5178A genotypic men, coffee consumption possibly reduced the risk of anemia (P for trend = 0.049). However, after the aforementioned adjustment, the statistical significance disappeared (P for trend = 0.137).

Conclusions

This exploratory cross-sectional analysis suggests that Mt5178 C/A polymorphism modulates the effects of coffee consumption on erythrocytic parameters and the risk of anemia in male Japanese health check-up examinees.

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.

NADH dehydrogenase subunit-2 237 Leu/Met polymorphism modifies effects of cigarette smoking on risk of elevated levels of serum liver enzyme in male Japanese health check-up examinees: a cross-sectional study

Background

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism reportedly influences the effects of cigarette smoking on respiratory function, risk of dyslipidemia, serum non-high-density lipoprotein cholesterol levels, hematological parameters and intraocular pressure. The objective of this study was to investigate whether ND2-237 Leu/Met polymorphism modifies the effects of cigarette smoking on serum liver enzyme levels in male Japanese health check-up examinees.

Methods

A total of 421 male subjects (mean age ± SD, 54.1 ± 7.7 years) were selected from among individuals visiting the hospital for regular medical check-ups. After ND2-237 Leu/Met genotyping, a cross-sectional study assessing the combined effects of ND2-237 Leu/Met polymorphism and cigarette smoking on serum aspartate aminotransferase levels, serum alanine aminotransferase (ALT) levels and serum gamma-glutamyltransferase (GGT) levels was then conducted.

Results

No statistically significant differences in serum liver enzyme levels among the three smoking status groups (never- or ex-smokers, 1–20 cigarettes smoked per day and >20 cigarettes smoked per day) by ND2-237 Leu/Met genotype were observed. However, for men with ND2-237Met, cigarette smoking significantly increased the risk of elevated levels of serum ALT (>30 U/L) or serum GGT (≥60 U/L or >51 U/L) (P for trend = 0.031, P for trend = 0.007 and P for trend = 0.004, respectively). After adjustment for age, body mass index, alcohol consumption, coffee consumption, antihypertensive treatment and antidiabetic treatment, a significant association between cigarette smoking and risk of elevated levels of serum ALT (>30 U/L) or serum GGT (≥60 U/L or >51 U/L) was also observed (P for trend = 0.032, P for trend = 0.019 and P for trend = 0.009, respectively). Surprisingly, for men with ND2-237Leu, cigarette smoking significantly decreased the risk of elevated levels of serum ALT (>30 U/L or ≥25 U/L) (P for trend = 0.026 and P for trend = 0.003, respectively).

Conclusions

Cigarette smoking appears to increase the risk of elevated levels of serum ALT or serum GGT in ND2-237Met genotypic men, but to decrease the risk of elevated levels of serum ALT in ND2-237Leu genotypic men.

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.

Joint effects of mitochondrial DNA 5178 C/A polymorphism and coffee consumption or alcohol consumption on clustering of cardiovascular risk factors in middle-aged Japanese men: a cross-sectional study

Background

Longevity-associated mitochondrial DNA 5178 (Mt5178) C/A reportedly modulates the effects of coffee consumption on the risk of hypertension, dyslipidemia and abnormal glucose tolerance, and those of alcohol consumption on the risk of hypertension, dyslipidemia and hyperuricemia in middle-aged Japanese men. However, there has been no research examining whether Mt5178 C/A polymorphism influences the effects of coffee consumption or alcohol consumption on the clustering of cardiovascular risk factors (CRFs).

Methods

A total of 332 male subjects (mean age ± SD, 52.8 ± 7.8 years) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effects of Mt5178 C/A polymorphism and coffee consumption or alcohol consumption on the clustering of CRFs, namely hypertension, abnormal glucose tolerance, hyper-low-density lipoprotein cholesterolemia, hypo-high density lipoprotein cholesterolemia, hypertriglyceridemia and hyperuricemia, was then conducted.

Results

After adjustment for confounding factors, significant and negative associations were observed between coffee consumption and clustering of ≥2 CRFs in subjects with Mt5178C. The adjusted odds ratio (OR) for the clustering of ≥2 or ≥3 CRFs was significantly lower in subjects who consumed 1–3 cups of coffee per day than in those who consumed <1 cup of coffee per day (OR = 0.496, 95% confidence interval (CI): 0.249–0.989, and OR = 0.369, 95% CI: 0.165–0.826, respectively). On the other hand, after adjustment, positive associations between coffee consumption and clustering of ≥2 CRFs were observed in subjects with Mt5178A. However, these associations did not reach a significant level. For Mt5178C genotypic men, the adjusted OR for the clustering of ≥2 or ≥3 CRFs was significantly higher in daily drinkers than in occasional drinkers (OR = 2.737, 95% CI: 1.361–5.502, and OR = 3.024, 95% CI: 1.269–7.210, respectively). On the other hand, the association between Mt5178A genotype and the clustering of ≥2 or ≥3 CRFs did not appear to depend on alcohol consumption.

Conclusions

The present results suggest that Mt5178 C/A polymorphism modifies the effects of coffee consumption or alcohol consumption on the clustering of CRFs in middle-aged Japanese men.

Difference in effects of cigarette smoking or alcohol consumption on serum non-high-density lipoprotein cholesterol levels is related to mitochondrial DNA 5178 C/A polymorphism in middle-aged Japanese men: a cross-sectional study

BACKGROUND

Mitochondrial DNA 5178 cytosine/adenosine (Mt5178 C/A) polymorphism is associated with longevity in the Japanese. The purpose of this study is to investigate whether Mt5178 C/A polymorphism modifies the effects of habitual smoking or habitual drinking on serum non-high-density lipoprotein (non-HDL) cholesterol levels in middle-aged Japanese men.

METHODS

A total of 394 male subjects (age 53.9 ± 7.9 years; mean ± SD) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effects of Mt5178 C/A polymorphism and cigarette smoking or alcohol drinking on serum non-HDL cholesterol levels was conducted. High levels of serum non-HDL cholesterol were defined as serum non-HDL cholesterol levels ≥160 mg/dl or ≥190 mg/dl.

RESULTS

For men with Mt5178A, cigarette smoking may increase serum non-HDL cholesterol levels (P for trend < 0.001), as well as the risk of high levels of non-HDL cholesterol (serum non-HDL cholesterol levels ≥160 mg/dl, P for trend < 0.001; serum non-HDL cholesterol levels ≥190 mg/dl, P for trend = 0.004). On the other hand, for men with Mt5178C, after adjusting for age and body mass index, alcohol consumption may decrease serum non-HDL cholesterol levels (P for trend = 0.043) and the risk of high levels of non-HDL cholesterol (serum non-HDL cholesterol level ≥160 mg/dl, P for trend = 0.005).

CONCLUSIONS

These gene-environment interactions on serum non-HDL cholesterol levels may contribute to the establishment of individualized prevention of the risk of high levels of serum non-HDL cholesterol.

Unexpected combined effects of NADH dehydrogenase subunit-2 237 Leu/Met polymorphism and green tea consumption on renal function in male Japanese health check-up examinees: a cross-sectional study

Background

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity in Japanese. A previous study has shown that ND2-237 Leu/Met polymorphism modulates the effects of green tea consumption on risk of hypertension. For men with ND2-237Leu, habitual green tea consumption may reduce the risk of hypertension. Moreover, there is a combined effect of ND2-237 Leu/Met polymorphism and alcohol consumption on risk of mildly decreased estimated glomerular filtration rate (eGFR) (<90 ml/min/1.73 m²). Several beneficial effects of green tea on the kidney have been reported. The objective of this study was to investigate whether ND2-237 Leu/Met polymorphism modifies the effects of green tea consumption on risk of mildly decreased eGFR in male Japanese health check-up examinees.

Results

For ND2-237Leu genotypic men, after adjustment for confounding factors, green tea consumption may increase the risk of mildly decreased eGFR (P for trend = 0.016). The adjusted odds ratio (OR) for mildly decreased eGFR was significantly higher in subjects with ND2-237Leu who consume ≥6 cups of green tea per day than those who consume ≤1 cup of green tea per day (adjusted OR = 5.647, 95% confidence interval: 1.528-20.88, P = 0.009). On the other hand, for ND2-237Met genotypic men, green tea consumption does not appear to determine the risk of mildly decreased eGFR.

Conclusion

The present results suggest that ND2-237 Leu/Met polymorphism unexpectedly modifies the effects of green tea consumption on eGFR and the risk of mildly decreased eGFR in male Japanese subjects.

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.

Factors associated with dietary habits and mood states affecting taste sensitivity in Japanese college women

We conducted a cross-sectional survey to evaluate the factors associated with dietary habits and mood states affecting taste sensitivity in 127 Japanese college women with a mean age of 19.2 y. Differential thresholds for the four basic tastes on the tongue were determined by the filter paper disc method, while dietary intake was assessed using a food frequency questionnaire. Psychological mood states were evaluated by the Profile of Mood State (POMS) questionnaire. Differential thresholds for saltiness and bitterness in alcohol drinkers were higher than those in alcohol non drinkers, whereas differential thresholds for the other tastes did not differ significantly between any of the stratified groups. Canonical correlation analysis revealed that among the five POMS mood states, POMS fatigue scores showed relatively stronger association with combined variables of taste thresholds. Logistic regression analysis revealed significant involvement of zinc and iron intake, and that POMS fatigue and anger scores affected the differential threshold for sourness. Specific mood and dietary factors were shown to be associated with sensitivity to sourness and bitterness. Among the five POMS mood states, high POMS fatigue scores and low POMS anger scores appeared to be associated with decreased taste sensitivity.

LDL-cholesterol and body mass index among Japanese schoolchildren: a population-based cross-sectional study

Background

Serum low-density lipoprotein cholesterol (LDL-C) is one of the most important risk factors for coronary heart disease. The aim of the present study was to investigate the relationship between LDL-C and body mass index (BMI) in population-based Japanese schoolchildren.

Methods

The subjects comprised all fourth graders and seventh graders in Ina Town, Saitama Prefecture, Japan, during 2002-2009. Information about each subject’s age, sex, and family history of hypercholesterolemia was collected using a self-administered questionnaire. The body height, weight, and LDL-C were measured for each child. LDL-C was measured using the direct method. According to the LDL-C criteria of the Japan Atherosclerosis Society, LDL-C level was categorized into three subgroups: acceptable, < 110 mg/dL; borderline, 110-139 mg/dL; and high, ≥ 140 mg/dL. Children with either borderline or high LDL-C level were considered to have high-normal LDL-C (HLDL-C).

Results

Data from a total of 5869 subjects were analyzed. A higher BMI category was associated with a higher prevalence of HLDL-C regardless of sex or grade level (P < 0.05). When compared with the <50th percentile BMI category, the odds ratio (OR) for HLDL-C was statistically significant in the 75th to 84th percentile category of fourth-grade boys (OR: 1.95, 95% confidence interval (95% CI): 1.28-2.97), the 85th to 94th percentile of fourth-grade girls (2.52, 1.74-3.64), and the 85th to 94th percentile of seventh-grade boys (2.04, 1.31-3.20) and girls (1.90, 1.24-2.91).

Conclusion

A statistically significant association between LDL-C levels and BMI was observed in Japanese school children.

A cross-sectional study of the association between working hours and sleep duration among the Japanese working population

OBJECTIVES

This study aimed to clarify the association between long working hours and short sleep duration among Japanese workers.

METHODS

We selected 4,000 households from across Japan by stratified random sampling and conducted an interview survey of a total of 662 participants (372 men; 290 women) in November 2009. Logistic regression analyses were performed using "sleep duration <6 hours per day" as a dependent variable to examine the association between working hours/overtime hours and short sleep duration.

RESULTS

When male participants who worked for ≥7 but <9 hours per day were used as a reference, the odds ratio (OR) for short sleep duration in those who worked for ≥ 11 hours was 8.62 (95% confidence interval [CI]: 3.94-18.86). With regard to overtime hours among men, when participants without overtime were used as a reference, the OR for those whose period of overtime was ≥ 3 hours but <4 hours was 3.59 (95% CI: 1.42-9.08). For both men and women, those with long weekday working hours tended to have a short sleep duration during weekdays and holidays.

CONCLUSIONS

It is essential to avoid working long hours in order to prevent short sleep duration.

Combined effect of mitochondrial DNA 5178 C/A polymorphism and alcohol consumption on estimated glomerular filtration rate in male Japanese health check-up examinees: a cross-sectional study

Background

Prevention of chronic kidney disease (CKD) is a major public health issue. Although several studies have been performed on the association between alcohol consumption and CKD or renal function, it remains controversial. Numerous genetic polymorphisms have been reported to be associated with CKD and kidney function. Mitochondrial DNA cytosine/adenine (Mt5178 C/A) polymorphism is associated with longevity in Japanese. This polymorphism modifies the effects of alcohol consumption on blood pressure, risk of hypertension, serum triglyceride levels, risk of hyper-LDL cholesterolemia and serum uric acid levels. The objective of this study was to investigate whether Mt5178 C/A polymorphism modifies the effects of alcohol consumption on renal function in male Japanese health check-up examinees.

Methods

A total of 394 male subjects aged 29–76 years were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the combined effects of Mt5178 C/A polymorphism and habitual drinking on the risk of mildly decreased estimated glomerular filtration rate (eGFR) (<90 ml/min/1.73 m²) was conducted.

Results

For Mt5178A genotypic men, habitual drinking may increase eGFR (P for trend = 0.003) or reduce the risk of mildly decreased eGFR (P for trend = 0.003). Daily drinkers had a significantly higher eGFR than non-drinkers (P = 0.005). The crude odds ratio for decreased eGFR was significantly lower in daily drinkers than in non-drinkers (odds ratio = 0.092, 95% confidence interval: 0.012-0.727, P = 0.024). On the other hand, for Mt5178C genotypic men, habitual drinking does not appear to affect eGFR.

Conclusion

The present results suggest a joint effect of Mt5178 C/A polymorphism and alcohol consumption on eGFR and the risk of mildly decreased eGFR in male Japanese subjects.

Eating behaviors and overweight among adolescents: a population-based survey in Japan

OBJECTIVES

The aim of the present study was to investigate the relationship between eating behaviors and overweight among population-based adolescents in Japan.

METHODS

Study subjects comprised adolescents in the seventh grade (age range, 12-13 years) from Ina, a town in Saitama Prefecture, Japan, between 1999 and 2008. The height and weight of the subjects were measured, and information concerning eating behaviors (eating speed and eating until full) was obtained using a self-administered questionnaire.

RESULTS

Among boys (n = 1586), fast eating speed significantly increased the odds ratio (OR) for overweight when compared with medium eating speed, regardless of eating until full or not; moreover, a more marked increase in the OR was observed among boys eating until full (OR: 2.78, 95% confidence interval: 1.76-4.38) than among those not eating until full (2.43, 1.41-4.20). Among girls (n = 1542), fast eating speed led to a significant increase in the OR in those eating until full; however, no significant increases were observed in the OR in those eating quickly and not until full.

CONCLUSIONS

Among adolescents, fast eating speed was associated with overweight; furthermore, the combination of both fast eating speed and eating until full may have a significant effect on overweight.

Why not use your own body weight to prevent falls? A randomized, controlled trial of balance therapy to prevent falls and fractures for elderly people who can stand on one leg for ≤15 s

BACKGROUND

Maintaining or improving motor (balance) ability is essential to extending the healthy lifespan of elderly people, and developing effective and efficient strategies to prevent falls of elderly people is an urgent. The purpose of this study was to determine the effects of balance exercise on fall and fracture prevention for elderly people with poor balance.

METHODS

A 6-month, randomized controlled trial was conducted to verify whether one-leg standing with eyes open for a total of 1 min, three times a day (dynamic flamingo exercise) prevents falls and fractures. Setting and participants were elderly people ≥75 years of age and one-leg standing time ≤15.0 s living in their own home. They were visiting orthopaedic clinics for orthopaedic handicaps. Subjects with poor balance were allowed to hold on to something. If a subject's lifted leg touched the ground during the exercise, they were allowed to lift it again and continue so that they stood on one leg for a total of 60 s.

RESULTS

The dynamic flamingo exercise group (410 people; 86 men, 324 women) and the no exercise group (455 people; 78 men, 377 women) were compared. After dynamic flamingo exercise for 6 months, significant differences were seen in the increase in one-leg standing time with eyes open (men right/left, women right/left), in the improvement in independence in daily living (women), number of people who fell during the 6 months (women), and adverse events (women). The number of fractures was not significantly different for men or women.

CONCLUSIONS

Dynamic flamingo exercise prevents falls but no significant difference was demonstrated in fracture prevention in elderly women with poor balance.

Personal features and dropout from diabetic care

OBJECTIVE

To investigate the personal features associated with dropout from regular outpatient care among persons with type 2 diabetes mellitus (DM).

METHODS

A total of 160 DM patients were enrolled in the study. As a retrospective analysis, outpatient's clinical characteristics, lifestyle, or social features were gathered from their medical records or interview sheets. All the subjects were divided into two groups by adherence to diabetic care, namely, 'dropout case' (DC), or 'ongoing case' (OC), and were subjected to comparative analysis. We called the patients who did not receive outpatient treatment from the clinic on a regular basis, including treatment from other clinics or dropout of diabetic care, as DC. In contrast, patients who regularly visited the clinic were defined as OC. An unconditional multiple logistic regression analysis was performed to analyze the association of a dherence to diabetic care with several personal features.

RESULTS

Sixty-eight of 160 subjects (42.5%) were recognized as DC. The remaining 92 subjects (57.5%) were considered as OC. Young age (p=0.045), low plasma glucose (p=0.005) and hemoglobin A1c (HbA1c) levels (p=0.005), nonmedication (p<0.001) and no past history of DM (p=0.007) at the initial visit were the features related to dropout by crude analysis. Even after adjustment for age and gender by multivariate analysis, there remained significant inverse associations of dropout with HbA1c level, medical treatment (oral agents or insulin) and previous DM history. Neither occupation, distance from residence to clinic, smoking habit nor drinking habit was associated with dropout. Dropout mostly occurred after the initial or second visit.

CONCLUSIONS

A mild condition of DM may be related to dropout from regular outpatient care. It may be necessary to clearly show the objectives and importance of regular visit to an outpatient clinic for diabetic care, particularly for screened mild DM cases in public health activities.