Relative Importance of Central and Peripheral Adiposities on Cardiometabolic Variables in Females: A Japanese Population-Based Study

In epidemiological studies, there is little evidence regarding the relative impact of central adiposity and peripheral adiposity on cardiometabolic risk factors, especially in Asian populations. This study investigated associations between central-to-peripheral fat ratios and cardiometabolic variables using data from a population-based study of Japanese women. The source population was composed of 1800 women aged 50 yr or older at the 15th- to 16th-yr follow-up survey of the Japanese Population-Based Osteoporosis Cohort Study. This study analyzed cross-sectional data from 998 women for whom complete information about body fat variables according to dual-energy X-ray absorptiometry, cardiometabolic variables, and potential confounding factors was available. Both before and after adjusting for potential confounding factors, trunk-to-appendicular fat ratios showed significant (p < 0.05) correlations with brachial-ankle pulse wave velocity, serum lipids, and hemoglobin A1c levels. Relationships between fat ratios and cardiometabolic variables were independent of relationships between fat volumes (in whole body or in trunk) and cardiometabolic variables. Furthermore, relationships between trunk-to-appendicular fat ratios and cardiometabolic variables were observed among women in the lowest tertile of total body fat (brachial-ankle pulse wave velocity, β = 0.08; high-density lipoprotein cholesterol, β = -0.32; low-density lipoprotein cholesterol, β = 0.15; and hemoglobin A1C, β = 0.16; p < 0.05, respectively). Central adiposity is more related to cardiometabolic variables than peripheral adiposity. Information on central-to-peripheral fat ratios is particularly valuable for the evaluation of relatively thin Japanese women.

Increased Ratio of Trunk-to-Appendicular Fat and Decreased Adiponectin: A Population-Based Study of School Children in Hamamatsu, Japan

Very few epidemiological studies have examined the relative impact of visceral fat and subcutaneous fat on serum adiponectin levels. Trunk-to-extremity fat ratio is reportedly a better surrogate for visceral fat than for subcutaneous fat. In the present study, we investigated the association between adiponectin and trunk-to-appendicular fat ratio (TAR) in a school population. The source population was all fifth graders (799 pupils) enrolled in the 2 elementary schools in Hamamatsu, Japan. Of the source population, we analyzed cross-sectional data from 609 children (mean age: 11.2 yr). TAR was evaluated by dual-energy X-ray absorptiometry and calculated as trunk fat mass divided by appendicular (arms and legs) fat mass. After stratification by tertiles of total body fat, multiple regression analysis was used to examine the relationships between adiponectin and TAR adjusted for potential confounding factors. In the highest tertile of total body fat, increasing TARs were significantly (p < 0.05) associated with decreasing serum adiponectin levels after stratification by total body fat (β = -0.32 in boys; β = -0.31 in girls). In the second tertile of total body fat, TAR in girls also showed significant inverse relationships with serum adiponectin levels (β = -0.27). Data from this population-based study demonstrated that an increased proportion of trunk fat is associated with decreased adiponectin in relatively overweight children, and also demonstrated that girls with a normal volume of body fat that follows a more centralized distribution show decreased adiponectin.

Trunk-to-Peripheral Fat Ratio Predicts Subsequent Blood Pressure Levels in Pubertal Children With Relatively Low Body Fat - Three-Year Follow-up Study

BACKGROUND

Only a few studies have examined the relationship between fat distribution measured by dual-energy X-ray absorptiometry (DXA) and blood pressure (BP), and no cohort study has targeted a pediatric population.

METHODS AND RESULTS

The source population comprised all students registered as fifth graders in the 2 elementary schools in Hamamatsu, Japan. Of these, 258 children participated in both baseline (at age 11) and follow-up (at age 14) surveys. Body fat distribution was assessed using trunk-to-appendicular fat ratio (TAR) and trunk-to-leg fat ratio (TLR) measured by DXA. Relationships between BP levels and fat distribution (TAR or TLR) were examined after stratification by tertiles of whole-body fat.Systolic BP at follow-up was significantly (P<0.05) associated with both TAR (boys, β=0.33; girls β=0.36) and TLR (girls β=0.35) at baseline, after adjusting for confounding factors such as baseline BP in the lowest tertile of whole-body fat. Moreover, adjusted means of systolic and diastolic BPs in girls showed a significant increase from the lowest to highest tertile of TAR within the lowest tertile of whole-body fat.

CONCLUSIONS

Body fat distribution in childhood could predict subsequent BP levels in adolescence. Children with a relatively low body fat that is more centrally distributed tended to show relatively high BP later on. (Circ J 2016; 80: 1838-1845).

Inverse association between height increase and LDL cholesterol during puberty: A 3-year follow-up study of the Fukuroi City

OBJECTIVES

Few studies have reported on the association between changes in serum low-density lipoprotein cholesterol (LDL-C) and height increase. We investigated the association between LDL-C change and height increase during puberty in a 3-year follow-up study in Fukuroi City, Japan.

METHODS

The source population was all fifth grade 2,515 students enrolled in any public school in Fukuroi, Japan in 2008, 2009, and 2010. The follow-up survey was conducted in eighth grade students in 2011, 2012, and 2013. In total, 2,225 adolescents were followed. To evaluate the relationships between height increases and changes in LDL-C, a regression analysis was conducted after stratification by tertiles of weight change (LW: lowest group, MW: middle group, and HW: highest group).

RESULTS

In each weight change tertile, serum LDL-C significantly decreased from the lowest to highest tertiles of height change (LW: regression coefficient (B) = -0.12, MW: B = -0.07, HW: B = -0.08 in males; MW: B = -0.17, HW: B = -0.14 in females). The association between height increases and LDL-C was significantly stronger than that between weight increases and LDL-C (male: B = -0.609 and 95% CI -0.836 to -0.382 in height, B = 0.008 and 95% CI -0.193 to 0.209 in weight; female: B = -0.963 and 95% CI -1.301 to -0.624 in height, B = 0.366 and 95% CI 0.058-0.675 in weight).

CONCLUSIONS

Serum LDL-C decreased with increasing height, independent of increases in weight. The association between LDL-C and height is stronger than that between LDL-C and weight. Am. J. Hum. Biol. 28:330-334, 2016. © 2015 Wiley Periodicals, Inc.

Cardiovascular response to short-term fasting in menstrual phases in young women: an observational study

Background

Menstrual cycle-related symptoms are an important health issue for many women, and some may affect cardiac autonomic regulation. In the present study, we evaluated the cardiovascular and physiological stress response to 12-h short-term fasting in the menstrual phases of healthy young women.

Methods

We performed a randomized crossover study. Subjects were seven female university students (age: 22.3 ± 1.0 years). The experiments comprised four sessions: meal intake in the follicular phase, meal intake in the luteal phase, fasting in the follicular phase, and fasting in the luteal phase. All subjects participated in a total of four experimental sessions during two successive phases (follicular and luteal phase in the same menstrual cycle, or luteal phase and follicular phase in the next menstrual cycle) according to a randomized crossover design. R-R intervals were continuously recorded before and after meals, and power spectral analysis of heart rate variability was performed. Other physiological data were obtained before and 20, 40, 60, and 80 min after meal intake or after the corresponding time point of meal intake (fasting in the follicular or luteal phase).

Results

Heart rate decreased during fasting in the follicular and luteal phases. High frequency power increased during fasting in the follicular and luteal phases. In addition, salivary cortisol concentrations decreased during fasting in the luteal phase.

Conclusions

In the present study, short-term fasting resulted in higher parasympathetic activity and lower cortisol levels in the luteal phase in these young women. These results indicate a possibility to produce an anti-stress effect in the luteal phase, which may reduce menstrual symptoms.

Influences of peers' and family members' body shapes on perception of body image and desire for thinness in Japanese female students

PURPOSE

The present study investigated the influence of peers' and family members' body shapes on the perception of body image and desire for thinness in Japanese female students.

METHODS

The study included 342 female, Japanese university students between the ages of 18 years and 22 years. They completed an anonymous questionnaire, which included questions related to anthropometry and body perception. Eating behavior was assessed by the Japanese version of the Eating Attitude Test-26.

RESULTS

Many students overestimated their body shape (81.2% of underweight students and 74.6% of normal students) and had a desire for thinness (41.0% of underweight students, 88.2% of normal students, and 100% of overweight students). One of the main reasons for the overestimation of their body shape was comparison with others. Participants who were interested in a friend's body shape were almost three times more likely to have a desire for thinness than those who were not interested in a female friend's body shape (odds ratio: 3.06, P=0.014).

CONCLUSION

The results indicate a possibility that a female Japanese student's young female friends' body shapes, influences her desire for thinness or her perception of her own body shape.

Hot water immersion induces an acute cytokine response in cervical spinal cord injury

PURPOSE

The dysfunctional sympathetic nervous system in individuals with cervical spinal cord injury (CSCI) impairs adrenergic responses and may, therefore, contribute to the blunted post-exercise cytokine response. The purpose of this study was to investigate an alternative way to exercise to induce an acute cytokine response by passive core temperature elevation in CSCI.

METHODS

Seven male participants with a motor complete CSCI and 8 male able-bodied controls were immersed for 60 min in water set at a temperature 2 °C above the individuals' resting oesophageal temperature. Blood was collected pre, post, and every hour up to 4 h post-immersion.

RESULTS

Hot water immersion resulted in an IL-6 plasma concentration mean increase of 133 ± 144 % in both groups (P = 0.001). On a group level, IL-6 plasma concentrations were 68 ± 38 % higher in CSCI (P = 0.06). In both groups, IL-8 increased by 14 ± 11 % (P = 0.02) and IL-1ra by 18 ± 17 % (P = 0.05). Catecholamine plasma concentrations were significantly reduced in CSCI (P < 0.05) and did not increase following immersion.

CONCLUSIONS

Passive elevation of core temperature acutely elevates IL-6, IL-8 and IL-1ra in CSCI despite a blunted adrenergic response, which is in contrast to earlier exercise interventions in CSCI. The present study lays the foundation for future studies to explore water immersion as an alternative to exercise to induce an acute cytokine response in CSCI.

Trabecular bone score may improve FRAX® prediction accuracy for major osteoporotic fractures in elderly Japanese men: the Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) Cohort Study

FRAX® is widely used to evaluate fracture risk of individuals in clinical settings. However, FRAX® prediction accuracy is not sufficient, and improvement is desired. Trabecular bone score, a bone microarchitecture index, may improve FRAX® prediction accuracy for major osteoporotic fractures in community-dwelling elderly Japanese men.

INTRODUCTION

To improve fracture risk assessment in clinical settings, we evaluated whether the combination of FRAX® and Trabecular Bone Score (TBS) improves the prediction accuracy of major osteoporotic fractures (MOFs) in elderly Japanese men compared to FRAX® alone.

METHODS

Two thousand and twelve community-dwelling men aged ≥65 years completed the Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) Baseline Study comprising lumbar spine (LS) and femoral neck areal bone mineral density (aBMD) measurements, and interviews regarding clinical risk factors required to estimate 10-year risk of MOF (hip, spine, distal forearm, and proximal humerus) using the Japanese version of FRAX® (v.3.8). TBS was calculated for the same vertebrae used for LS-aBMD with TBS iNsight software (v.2.1). MOFs that occurred during the follow-up period were identified by interviews or mail and telephone surveys. Prediction accuracy of a logistic model combining FRAX® score and TBS compared to FRAX® alone was evaluated by area under receiver-operating characteristic curves (AUCs), as well as category-free integrated discrimination improvement (IDI) and net reclassification improvement (NRI).

RESULTS

We identified 22 men with MOFs during 8140 person-years (PY) of follow-up among 1872 men; 67 men who suffered from fractures other than MOFs were excluded. Participants with MOFs had significantly lower TBS (p = 0.0015) and higher FRAX® scores (p = 0.0089) than those without. IDI and NRI showed significant improvements in reclassification accuracy using FRAX® plus TBS compared to FRAX® alone (IDI 0.006 (p = 0.0362), NRI 0.452 (p = 0.0351)), although no difference was observed in AUCs between the two.

CONCLUSIONS

TBS may improve MOF prediction accuracy of FRAX® for community-dwelling elderly Japanese men.

Greater milk intake is associated with lower bone turnover, higher bone density, and higher bone microarchitecture index in a population of elderly Japanese men with relatively low dietary calcium intake: Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) Study

The effects of milk intake on bone health are not clear in elderly Asian men with low dietary calcium intake. This study showed that greater milk intake is associated with lower bone turnover, higher bone density, and higher bone microarchitecture index in community-dwelling elderly Japanese men.

INTRODUCTION

The consumption of milk or dairy products is widely recommended for maintaining bone health regardless of gender or age. However, little evidence exists on the beneficial effects of milk intake on bone health in elderly Japanese men characterized with relatively low dietary calcium intake. Here we examined whether or not greater milk intake was associated with lower bone turnover, higher bone density, and stronger bone microarchitecture in community-dwelling elderly Japanese men.

METHODS

Interviews were conducted to obtain information on medical history and lifestyle, including the amount of habitual milk intake, nutrient intake calculations based on a 1-week food diary, and measurements of areal bone mineral density (aBMD) at the lumbar spine (LS), total hip (TH), and femoral neck (FN) by dual-energy x-ray absorptiometry (DXA), trabecular bone score (TBS) using DXA images at LS, and biochemical markers of bone turnover in sera. Participants with a history of diseases or medications that affect bone metabolism, or with missing data, were excluded from the analysis.

RESULTS

The median intake of milk in the 1479 participants (mean age, 73.0 ± 5.1 years) was one glass of milk per day. Bone turnover markers showed a decreasing trend (p < 0.05) and aBMD at TH (p = 0.0019) and FN (p = 0.0057) and TBS (p = 0.0017) showed increasing trends with greater milk intake after adjusting for demographic and behavioral confounding factors. This association was attenuated after further adjusting for nutrient intake, in particular, calcium intake.

CONCLUSIONS

Greater milk intake was associated with lower bone turnover, higher aBMD, and higher TBS in community-dwelling elderly Japanese men.

HDL subclasses are heterogeneous in their associations with body fat, as measured by dual-energy X-ray absorptiometry: the Kitakata Kids Health Study

BACKGROUND

Obesity, defined as the excessive accumulation of body fat, is frequently associated with low concentrations of high-density lipoprotein (HDL) cholesterol. However, HDL particles are heterogeneous in size and composition. HDL subclasses may be differentially associated with body fat.

METHODS

This study investigated associations between the cholesterol concentrations of HDL subclasses, as determined by high-performance liquid chromatography, and body fat variables, as measured by dual-energy X-ray absorptiometry. The source population was all ninth grade students who attended Shiokawa Junior High School in Japan.

RESULTS

Cross-sectional data on body fat and serum HDL subclasses were obtained for 87 students (72.5% of the source population). The cholesterol concentration of the large HDL subclass showed a significant (P<0.05) inverse relationship with whole body fat and trunk fat (r=-0.24 and -0.30), whereas the concentration of the small HDL subclass showed a significant positive relationship with these body fat variables (r=0.25 and 0.31). After adjusting for potential confounding factors, the mean concentration of small HDL significantly increased from the lowest to highest tertiles of trunk fat mass index.

CONCLUSION

These results indicate that HDL subclasses are heterogeneous in their associations with body fat variables that were accurately measured by dual-energy X-ray absorptiometry among Japanese students.

Eating behavior and perception of body shape in Japanese university students

PURPOSE

We investigated the relationship between eating behavior measured by the Dutch Eating Behaviour Questionnaire (DEBQ) and perception of body shape, examining the current physical status and 'ideal' physical parameters in females and males.

METHODS

The participants, 548 Japanese university students (age 19.2 ± 0.9 years, mean ± SD; 252 males, 296 females), completed a questionnaire which asked for their current physical status (e.g., weight and height), their ideal physical parameters, their perception of their current body shape, their ideal body shape, and their eating behaviors.

RESULTS

The ideal weight and ideal body mass index (BMI) were significantly higher than the current weight and BMI in the males, but significantly lower in the females. Among the females, the ideal body shape was smaller than their perception of current body shape. The DEBQ scores for restrained, emotional, and external eating were higher in the females than the males among the normal-weight participants, and among the underweight participants, the restrained eating and external eating scores were higher in the females than the males. Restrained eating was negatively associated with the discrepancy between the current and ideal weight, BMI, and body shape in both the males and females. Emotional eating was negatively associated with the discrepancy in current/ideal BMI and body shape only in the females.

CONCLUSIONS

At least in Japanese university students, the gender differences in ideal body shape are related to eating behavior.

Fat mass is positively associated with bone mass in relatively thin adolescents: data from the Kitakata Kids Health Study

Epidemiologic studies have found that higher body weight is associated with better bone health. Body weight consists of both fat mass (FM) and lean soft tissue mass (LSTM). Previous studies have examined the effects of FM levels during childhood on bone health, with conflicting results. In the present study, we investigated the independent contributions of FM to bone mass in Japanese adolescents. Subjects were 235 adolescents aged 15-18 years old in August 2010 and in August 2013 from the Kitakata Kids Health Study in Japan. We obtained cross-sectional data on body composition as well as bone mineral density (BMD). Body composition and BMD were measured using a dual-energy X-ray absorptiometry scanner. We found moderate and positive relationships between FM index and LSTM index (males, r=0.69; females, r=0.44). To verify a potentially additive effect of FM on the variance of bone variables beyond LSTM, we assessed the association between FM index and bone variables after stratification by tertiles of the LSTM index. In the lowest tertile of the LSTM index, FM index was significantly (P<0.05) associated with both femoral neck BMD (males, β=0.48; females, β=0.33) and whole body BMC (males, β=0.41; females, β=0.25). On the other hand, we found no significant associations between FM index and bone variables in other tertiles of the LSTM index. These findings indicate that FM can influence how high bone mass is obtained among relatively thin adolescents, but not among those who are of normal weight or overweight.

Renal function and bone mineral density in community-dwelling elderly Japanese men: the Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) Study

End-stage renal failure deteriorates bone mass and increases fracture risk. However, there are conflicting reports in the literature regarding the effects of mild to moderate renal dysfunction on bone mineral density (BMD). We investigated the association between renal function and BMD at the spine and hip and bone metabolism markers in community-dwelling elderly Japanese men. From 2174 male volunteers aged ≥65 years, we examined 1477 men after excluding those with diseases or medications known to affect bone metabolism. Renal function was assessed by serum cystatin C and estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease Study equation. Bone metabolism was evaluated using levels of serum amino-terminal propeptide of type I procollagen (PINP) and tartrate-resistant acid phosphatase isoenzyme 5b (TRACP-5b), which represent bone metabolic status independent of renal function. eGFR was inversely associated with BMD after adjusting for potential confounders (P < 0.01). Cystatin C showed a weaker but significant association with BMD. eGFR was modestly positively associated with PINP levels (P = 0.04), although cystatin C concentrations were neither associated with PINP nor TRACP-5b levels. Since BMD integrates bone metabolism from the past to present, inverse associations between renal function and BMD may be attributed to past factors, such as obesity. Our findings suggest that low renal function does not affect bone metabolism in a population of community-dwelling elderly Japanese men. Longitudinal studies will be necessary to clarify whether low renal function affects bone loss.

Growth-related disappearance of the childhood relationship between height and blood pressure levels

CONTEXT

Although there is a positive relationship between height and blood pressure (BP) levels in children, there are no reports regarding the association between height and BP levels in adolescents and adults.

OBJECTIVE

This study examined whether there is an association between height and BP levels in Japanese adolescents.

METHODS

The source population was all fifth (10 and 11-year-olds) and ninth graders (14 and 15-year-olds) who attended 11 elementary schools and five junior high schools in the Iwata area from 2002-2008. School-based screenings were conducted annually by the local government from April to June. Data obtained from health examinations were analysed, including anthropometric measurements and BP levels, for 11 780 children (98.7% of the source population).

RESULTS

Height showed significant positive relationships with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in childhood and in adolescent males. In contrast, the relationship between height and SBP was significantly weaker in adolescent females than in childhood and there was no significant relationship between height and DBP in adolescent females.

CONCLUSION

The relationship between height and SBP was attenuated by development in females and the relationship between height and DBP disappeared.

Relationship of a desire of thinness and eating behavior among Japanese underweight female students

OBJECTIVE

We conducted a questionnaire survey among Japanese female students to explore the influence of a desire for thinness and dietary behaviors on the development of eating disorders.

METHODS

Self-reported measures of socio-demographic characteristics, body weight perception, height and weight, and dietary and exercise behavior were completed by 631 female university students at 6 universities in Kyoto, Japan.

RESULTS

Many students had a desire for thinness (underweight students, 51.7 %; normal-weight students, 88.8 %), whereas ideal weight and body mass index were lower in the students with a desire for thinness than the students without a desire for thinness, and were also lower in the underweight students than the normal-weight students. The eating attitude test (EAT-26) scores of underweight students with a desire for thinness were higher than those of the normal-weight students with a desire for thinness. As a result of a logistic regression analysis, underweight, desire for thinness, and experience with weight control were positively associated with eating problems. Further, the association of eating problems increased along with the increase in the number of factors (underweight, desire for thinness, and experience with weight control).

CONCLUSIONS

These results indicate that underweight females have strong associations with eating problems.

Association of rapid weight gain during early childhood with cardiovascular risk factors in Japanese adolescents

Background

Because of the lack of relevant data, we investigated the association between rapid weight gain (RWG) during early childhood and cardiovascular risk factors in Japanese adolescents.

Methods

The source population comprised 2285 adolescents aged 13 to 14 years enrolled in any public school in Fukuroi City, Japan during 2008, 2009, or 2010. Since there are no private schools in this city, almost all adolescents who lived in the city went to 1 of these schools. We obtained data on blood pressure (BP), serum lipids, and anthropometry during adolescence, as well as anthropometry at birth, age 1.5 years, and age 3 years, from the Maternal and Child Health Handbook for 1624 children. RWG was defined as a change in body-weight standard deviation score greater than 0.67 from age 0 to 1.5 years or from age 1.5 to 3 years.

Results

After adjusting for confounding factors, adolescents who had RWG from 0 to age 1.5 years or from age 1.5 to 3 years were more likely to be overweight. Adolescents who had RWG during both periods were more likely to be overweight (odds ratio [OR], 6.37; 95% CI, 3.06–13.24), have unfavorable lipid concentrations (OR, 2.03; 95% CI, 1.15–3.58), and have high BP (OR: 2.36, 95% CI: 1.34–4.13). The associations with unfavorable lipid concentrations and high BP disappeared after further adjusting for current body mass index.

Conclusions

RWG during early childhood predicts unfavorable lipid concentrations and high BP in Japanese adolescents, and this relationship is mediated by body mass index in later life.

Increased ratio of trunk to appendicular fat and increased blood pressure: study of a general population of Hamamatsu children

BACKGROUND

Body fat distribution is defined as the pattern of fat deposits in different regions of the body and usually expressed as a ratio. There are few studies on the relationship between blood pressure and the ratio of central fat measured on dual-energy X-ray absorptiometry (DXA) in childhood.

METHODS AND RESULTS

The source population consisted of 521 fifth-grade children who attended elementary school in Hamamatsu, Japan, with 401 (77.0%) included in the study. Regional fat was determined using a DXA scanner in a mobile test room. The ratio of trunk to appendicular fat was calculated as trunk fat mass divided by appendicular (arms and legs) fat mass. In boys, the trunk-to-appendicular fat ratio was significantly related to systolic blood pressure and diastolic blood pressure after adjusting for confounding factors such as height and pubic hair appearance. In addition, an increase in trunk-to-appendicular fat ratio was related to an increase in blood pressure after adjusting for confounding factors including whole body fat volume and trunk fat volume. The relationship between fat distribution and blood pressure was not observed in girls.

CONCLUSIONS

An excessive proportion of trunk fat was related to increased blood pressure in the boys in a general population of Japanese children. The relationship between fat distribution and blood pressure was independent of the relationship between fat volume and blood pressure.

Combined influence of media use on subjective health in elementary school children in Japan: a population-based study

BACKGROUND

In recent years in Japan, electronic games, home computers, and the internet have assumed an important place in people's lives, even for elementary school children. Subjective health complaints have also become a problem among children. In the present study, we investigated the relationship between media use and health status in elementary school children in Japan.

METHODS

A cross-sectional school-based population survey was conducted in 2009 with a sample of fourth-, fifth-, and sixth-grade children (age range: 10-12 years old) in elementary schools in Japan (n = 3,464). Self-reported health, lifestyle habits, and time spent using media were assessed.

RESULTS

The use of games, television, and personal computers was significantly associated with lifestyle (p < 0.05) and subjective health (p < 0.05). In addition, the use of games, the use of television, and the use of personal computers were mutually associated. The greater the number of media used for more than 1 hour was, the higher the odds ratio of the association of media use with unhealthy lifestyle and subjective health complaints was. The plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints.

CONCLUSIONS

Game, television, and personal-computer use were mutually associated, and the plural use of these media had stronger associations with unhealthy lifestyle and subjective health complaints. Excessive use of media might be a risk for unhealthy lifestyle and subjective health complaints.

Relationship between body mass index at age 3 years and body composition at age 11 years among Japanese children: the Shizuoka population-based study

Background

A few studies reported an association between body weight during early childhood and body composition in later life, as measured by dual-energy X-ray absorptiometry (DXA); however, none of those studies investigated an East Asian population. In a Japanese population, we examined the association between body weight at age 3 years and body composition at age 11 years, as measured using DXA.

Methods

The source population was 726 fifth-grade school children enrolled at 3 public schools in Shizuoka Prefecture, Japan from 2008–2010. All children who lived in the study area went to 1 of these 3 schools. DXA was used to obtain data on body composition, and the Maternal and Child Health Handbook was used to calculate body mass index (BMI). The general linear model was used for statistical analysis.

Results

We were able to analyze data on body composition at age 11 years and BMI in early childhood for 550 children. BMI at age 3 and change in BMI z-score from birth to age 3 were positively associated with bone mineral content (BMC), fat-free soft tissue mass (FFSTM), and fat mass (FM) at age 11. After adjusting for confounding factors, mean BMC, FFSTM, and FM were significantly lower among children who were underweight at age 3 and significantly higher among children who were overweight at age 3, as compared with values for normal-weight children at age 3.

Conclusions

Among Japanese children, body weight at age 3 years predicts body composition at age 11 years.

[Association between normal weight obesity and diet behaviors in female students]

OBJECTIVES

The association between normal weight obesity and diet behavior and physical activity in female students was investigated in this study.

METHODS

The subjects were 530 female students aged 18-21 years from 6 universities in the Kyoto Prefecture, Japan. From January to July, 2010, the body fat and walk counts of these students were measured, and they answered a questionnaire. The questionnaire included questions on life environment, perception of body shape, dieting experiences, physical activities, sleeping habits, and diet behaviors. The Eating Attitude Test-26 (EAT-26) was used to evaluate diet behavior. Students with normal weight (18.5 < or = body mass index < 25 kg/m2; n = 439) were divided into high (n = 115), middle (n = 213), and low (n = 111) groups according to their percentage of body fat. Further, a comparative analysis was performed among the 3 groups.

RESULTS

From the results of the questionnaire, perception of body shape, desire for a particular body shape, reason for weight loss, success or failure in dieting, and time for sleep were significantly different among the 3 groups. Differences in physical activity were not significant among the groups. Factor III (Oral control) of EAT-26 was higher in the high group than in the low group.

CONCLUSION

High body fat was associated with diet behavior and a desire to lose weight in normal weight students. These results indicate that health education is necessary to establish and maintain appropriate body fat composition and dietary habits.

Association between vitamin K intake from fermented soybeans, natto, and bone mineral density in elderly Japanese men: the Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) study

SUMMARY

A cross-sectional analysis of 1,662 community dwelling elderly Japanese men suggested that habitual natto intake was significantly associated with higher bone mineral density (BMD). When adjustment was made for undercarboxylated osteocalcin levels, this association was insignificant, showing the natto-bone association to be primarily mediated by vitamin K.

INTRODUCTION

Low vitamin K intake is associated with an increased risk of hip fracture, but reports have been inconsistent on its effect on BMD. Our first aim was to examine the association between BMD and intake of fermented soybeans, natto, which contain vitamin K1 (20 μg/pack) and K2 (380 μg/pack). Our second aim was to examine the association between undercarboxylated osteocalcin (ucOC), a biomarker of vitamin K intake, and BMD to evaluate the role of vitamin K in this association.

METHODS

Of the Japanese men aged ≥65 years who participated in the baseline survey of the Fujiwara-kyo Osteoporosis Risk in Men study, 1,662 men without diseases or medications known to affect bone metabolism were examined for associations between self-reported natto intake or serum ucOC levels with lumbar spine or hip BMD.

RESULTS

The subjects with greater intake of natto showed significantly lower level of serum ucOC. Analysis after adjustment for confounding variables showed an association of greater intake of natto with both significantly higher BMD and lower risk of low BMD (T-score < -1 SD) at the total hip and femoral neck. This association became insignificant after further adjustment for ucOC level.

CONCLUSION

Habitual intake of natto was associated with a beneficial effect on bone health in elderly men, and this association is primarily due to vitamin K content of natto, although the lack of information on dietary nutrient intake, including vitamin K1 and K2, prevented us from further examining the association.

Serum undercarboxylated osteocalcin levels are inversely associated with glycemic status and insulin resistance in an elderly Japanese male population: Fujiwara-kyo Osteoporosis Risk in Men (FORMEN) Study

SUMMARY

Recent animal studies have demonstrated that undercarboxylated osteocalcin upregulates insulin secretion via osteoblast-insulin signaling. However, it remains unclear whether such a pathway exists in humans. This study showed that serum undercarboxylated osteocalcin levels were inversely associated with fasting plasma glucose, hemoglobin A(1c), and homeostasis model assessment of insulin resistance (HOMA-IR) levels in community-dwelling elderly Japanese men.

INTRODUCTION

Undercarboxylated osteocalcin (ucOC) was reported to increase insulin secretion and improve glucose tolerance via osteoblast-insulin signaling in animal-based studies. Whether this pathway also exists in humans is unknown. We aimed to clarify whether serum ucOC levels are associated with glycemic status and insulin resistance in the general Japanese population.

METHODS

We included 2,174 Japanese men (≥65 years) who were able to walk without aid from others and lived at home in four cities of Nara Prefecture. We excluded participants with a history of diseases or medications that affect bone metabolism, other than type 2 diabetes mellitus (T2DM). Fasting plasma glucose, glycated hemoglobin A(1c), and HOMA-IR levels were determined as outcome measures.

RESULTS

Of the 1,597 participants included in the analysis, both intact OC (iOC) and ucOC levels showed significant inverse correlations with all outcome measures, even after adjusting for potential confounders. Mean values of outcome measures showed a significant decreasing trend with higher quintiles of iOC or ucOC after adjusting for confounders. This trend remained significant for ucOC quintiles after further adjustment for iOC levels, but was not significant for iOC quintiles after adjusting for ucOC levels. These results were attenuated, but still apparent, after excluding participants receiving drug therapy for T2DM.

CONCLUSIONS

Levels of ucOC, but not iOC, were inversely associated with glycemic index and insulin resistance in a population of Japanese men. These findings will need to be confirmed with longitudinal studies.

Trends of allergic symptoms in school children: large-scale long-term consecutive cross-sectional studies in Osaka Prefecture, Japan

BACKGROUND

Trends in the prevalence rates of allergic symptoms in children have been discussed extensively, but it remains uncertain which symptoms increase or decrease over time owing to the lack of large-scale long-term consecutive cross-sectional studies performed on a representative population of children.

OBJECTIVE

To clarify the trends in the prevalence rates of allergic symptoms in Japanese children.

METHODS

Total population questionnaire surveys were conducted 15 times from 1975 to 2006 for all children attending public elementary schools in Osaka Prefecture, Japan, with the number of subjects ranging from 460,000 to 900,000. Parents of the children completed the questionnaire about allergic symptoms and other symptoms, including wheeze, physician-diagnosed atopic dermatitis, rhinitis, and itching eyes.

RESULTS

Response rates were consistently over 90%. The prevalence of wheezing was constant until 1983, then increased from 1983 until 1993, then stabilized at about 4.4%. The lifetime prevalence of atopic dermatitis increased to 24% by 1993, and then decreased. The prevalence of rhinitis increased to 25% by 2003, whereas the prevalence of non-seasonal symptoms plateaued from 1993 on at 11% and vernal symptoms increased. The prevalence of itching eyes continued to increase to 21% in 2006, and vernal symptoms increased sharply.

CONCLUSIONS

In Osaka Prefecture, Japan, the turning point when the prevalence of wheezing in schoolchildren had begun to increase was 1983. And the turning point when the increase in the prevalence of wheezing, atopic dermatitis, and non-seasonal allergic rhinitis turned to decrease or constant was 1993. The prevalence of rhinitis and itching eyes in spring was still increasing in 2006.