Number of siblings, birth order, and childhood overweight: a population-based cross-sectional study in Japan

Background

Although several studies have investigated the relationship between the number of siblings or birth order and childhood overweight, the results are inconsistent. In addition, little is known about the impact of having older or younger siblings on overweight among elementary schoolchildren. The present population-based study investigated the relationship of the number of siblings and birth order with childhood overweight and evaluated the impact of having younger or older siblings on childhood overweight among elementary schoolchildren in Japan.

Methods

Subjects comprised fourth-grade schoolchildren (age, 9–10 years) in Ina Town during 1999–2009. Information about subjects’ sex, age, birth weight, birth order, number of siblings, lifestyle, and parents’ age, height, and weight was collected by a self-administered questionnaire, while measurements of subjects’ height and weight were done at school. Childhood overweight was defined according to age- and sex-specific cut-off points proposed by the International Obesity Task Force. A logistic regression model was used to calculate the odds ratio (OR) and 95% confidence intervals (95% CI) of "number of siblings" or "birth order" for overweight.

Results

Data from 4026 children were analyzed. Only children (OR: 2.13, 95% CI: 1.45-3.14) and youngest children (1.56, 1.13-2.16) significantly increased ORs for overweight compared with middle children. A larger number of siblings decreased the OR for overweight (P for trend < 0.001). Although there was no statistically significant relationship between a larger number of older siblings and overweight, a larger number of younger siblings resulted in a lower OR for overweight (P for trend < 0.001).

Conclusions

Being an only or youngest child was associated with childhood overweight, and having a larger number of younger siblings was negatively associated with overweight. The present study suggests that public health interventions to prevent childhood overweight need to focus on children from these family backgrounds.

High-molecular-weight adiponectin and anthropometric variables among elementary schoolchildren: a population-based cross-sectional study in Japan

Background

Studies about the relationship between high-molecular-weight adiponectin (HMW-adn) and anthropometric variables among population-based elementary schoolchildren have been too limited, especially in Japan, where blood collection is not usually performed in the annual health examination at elementary schools. The objective of the present study was to investigate the relationship between HMW-adn and anthropometric variables (body mass index [BMI], percent body fat [%BF], waist circumference [WC], and waist-to-height ratio [WHtR]) among population-based elementary schoolchildren in Japan.

Methods

Subjects comprised all fourth-grade schoolchildren (9 or 10 years of age) in the town of Ina, Saitama Prefecture, Japan during 2005–2008 (N = 1675). After excluding 21 subjects because of refusal to participate or incomplete data, data from a total of 1654 subjects (846 boys and 808 girls) were analyzed. The height, weight, %BF, and WC of each subject were measured, while blood samples were drawn from the subjects to measure adiponectin levels (HMW-adn and total adiponectin). Childhood obesity was determined according to the age- and sex-specific cut-off points proposed by the International Obesity Task Force. Spearman’s correlation coefficients between adiponectin levels and anthropometric variables were calculated for each sex.

Results

The anthropometric variables were negatively correlated with HMW-adn in both boys and girls. Correlation coefficients of HMW-adn with anthropometric variables in the obesity group were consistently higher than those in the non-obesity group among both boys and girls. In addition, only WHtR was significantly correlated with HMW-adn regardless of sex and physique (obesity or non-obesity); the correlation coefficient was -0.386 among boys and -0.543 among girls in the obesity group, while it was -0.124 among boys and -0.081 among girls in the non-obesity group.

Conclusions

HMW-adn was negatively correlated with anthropometric variables, while the correlation coefficients of HMW-adn with anthropometric variables in the obesity group were consistently higher than those in the non-obesity group. Moreover, only WHtR was significantly associated with HMW-adn regardless of sex and physique. The results of this study suggested that it is useful to monitor WHtR as a surrogate for HMW-adn among elementary school students, especially obese children.

Secular trends in blood pressure among Japanese schoolchildren: a population-based annual survey from 1994 to 2010

Background

Monitoring secular trends in blood pressure (BP) among children is important in predicting subsequent hypertension and cardiovascular disease. We investigated secular trends in BP using data from population-based annual screenings of Japanese schoolchildren.

Methods

The participants were 10 894 children (all fourth graders between 1994 and 2010 and all seventh graders between 1997 and 2010) living in the town of Ina in Saitama Prefecture, Japan. Body height, weight, and BP were measured, after which children were classified as non-overweight, overweight, or obese. Trends in variables relative to calendar year were analyzed using regression models.

Results

Systolic BP was significantly associated with calendar year among fourth- and seventh-grade boys (−0.350 and −0.434 mm Hg/year, respectively) and fourth- and seventh-grade girls (−0.513 and −0.473 mm Hg/year, respectively) (all P < 0.001), respectively, over time. Systolic BP and calendar year were significantly negatively correlated regardless of physique or sex among all fourth graders, but not among obese seventh-grade girls. In addition, diastolic BP and calendar year did not significantly correlate among seventh-grade overweight or obese boys or obese seventh-grade girls.

Conclusions

BP decreased among fourth-grade schoolchildren in Ina during the past 17 years, regardless of sex or physique. However, BP and calendar year did not significantly correlate among obese seventh graders.

Mitochondrial DNA 5178 C/A polymorphism influences the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese men

Background

Several genetic polymorphisms have been reported to modify the effects of smoking on serum lipid levels. The objective of this study was to investigate whether longevity-associated mitochondrial DNA 5178 (Mt5178) C/A polymorphism modifies the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese subjects.

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 effect of Mt5178 C/A polymorphism and cigarette smoking on the risk of hypo-high-density lipoprotein (HDL) cholesterolemia, hyper-low-density lipoprotein (LDL) cholesterolemia or hypertriglyceridemia was conducted.

Results

For subjects with Mt5178C, the risk of hypo-HDL cholesterolemia increased with the number of cigarettes smoked daily (P for trend = 0.001). On the other hand, the association between Mt5178A genotype and the risk of hypo-HDL cholesterolemia did not appear to depend on the number of cigarettes smoked daily. For those with Mt5178A, the risk of hyper-LDL cholesterolemia or hypertriglyceridemia increased with cigarettes smoked daily (P for trend = 0.017 and P for trend = 0.002, respectively). However, the association between Mt5178C genotype and the risk of hyper-LDL cholesterolemia or hypertriglyceridemia did not depend on the number of cigarettes smoked daily.

Conclusions

The present results suggest that Mt5178 C/A polymorphism modulates the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese men.

Preferable forms of relaxation for health promotion, and the association between recreational activities and self-perceived health

Little research has been done on the association between relaxation and health. In the present study, by conducting a nationwide cross-sectional survey, we aimed to obtain scientific data on the preferable forms of relaxation for health promotion, and to clarify the associations between specific recreational activities and self-perceived mental and physical health. We selected 4,000 households by stratified random sampling from across Japan in November 2009 and used the interview method to collect data (number of subjects: 2,206). The questionnaire contained items on sleep, recreation status, recreational activities, and self-perceived mental and physical health status. We obtained responses from 1,224 adults (response rate: 55.5%). Insufficient rest from sleep, short sleep duration (<6 h/day), ineffective use of free time, and less free time used for activities other than rest showed independent positive associations with poor mental and physical health. The results of the logistic regression analyses showed significantly low adjusted odds ratios with regard to the status of poor mental and physical health for outings/walking among men (0.33 [95% confidence interval; 0.16-0.68] and 0.49 [0.26-0.90], respectively), and for community activities among women (0.19 [0.04-0.79] and 0.27 [0.09-0.77], respectively). Relaxation for the promotion of health should include both passive relaxation (rest) and active relaxation (recreation). In addition, ensuring sufficient sleep duration is important for passive relaxation, and engaging in outings/walking for men and community activities for women are important for active relaxation.

Sleep duration and overweight among elementary schoolchildren: a population-based study in Japan

Although a number of studies have investigated the relationship of sleep duration to overweight and obesity, studies conducted among population-based elementary schoolchildren have been limited in Japan. The aim of the present study was to investigate the relationship between sleep duration and overweight among elementary schoolchildren in Japan. The study subjects were all fourth-grade schoolchildren (9 or 10 years of age) in Ina-town, Saitama Prefecture, Japan from 1999 to 2008. Information concerning each subject's sex, age, and lifestyle was obtained using a self-administered questionnaire, while measurements of his or her height and weight were carried out. Childhood overweight was determined according to the definition established by the International Obesity Task Force. Data from 3,433 children were analyzed. In logistic regression analysis, a statistically significant dose-response relationship was observed between sleep duration and overweight among boys (p for trend = 0.014) but not among girls (p for trend = 0.149). Short sleep duration was associated with childhood overweight, and the sex difference in the association was observed. These findings suggested that it is important to consider sleep duration as part of any program to prevent overweight among elementary schoolchildren, especially among boys.

Living conditions, ability to seek medical treatment, and awareness of health conditions and healthcare options among homeless persons in Tokyo, Japan

Empirical data indicative of the health conditions and medical needs of homeless persons are scarce in Japan. In this study, with the aim of contributing to the formulation of future healthcare strategies for the homeless, we conducted a self-administered questionnaire survey and interviews at a park in Shinjuku Ward, Tokyo, to clarify the living conditions of homeless persons and their health conditions and awareness about the availability of medical treatment. Responses from 55 homeless men were recorded (response rate: 36.7%). With the exception of one person, none of them possessed a health insurance certificate. Half of the respondents reported having a current income source, although their modal monthly income was 30,000 yen($1 was approximately 90 yen). The number of individuals who responded "yes" to the questions regarding "Consulting a doctor on the basis of someone's recommendation" and "Being aware of the location of the nearest hospital or clinic" was significantly higher among those who had someone to consult when they were ill than among those who did not (the odds ratios [95% confidence intervals] were 15.00 [3.05-93.57] and 11.45 [1.42-510.68], respectively). This showed that whether or not a homeless person had a person to consult might influence his healthcare-seeking behavior. When queried about the entity they consulted (multiple responses acceptable), respondents mentioned "life support organizations" (61.1%) and "public offices" (33.3%). Overall, 94.5% of the respondents were aware of swine flu (novel influenza A (H1N1)). Their main sources of information were newspapers and magazines. On the basis of these findings, with regard to the aim of formulating healthcare strategies for homeless persons, while life support organizations and public offices play significant roles as conduits to medical institutions, print media should be considered useful for communicating messages to homeless persons.

Influence of mitochondrial DNA 5178 C/A polymorphism on serum cholesterol changes: a short-term follow-up in middle-aged Japanese men

OBJECTIVE

The mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism is reportedly associated with longevity in the Japanese population, and the Mt5178A genotype may exert anti-atherogenic effects. The aim of this study was to determine whether there were longitudinal differences in serum lipid levels between carriers of the Mt5178C genotype and those of the Mt5178A genotype and to assess the impact of these genotypes on serum cholesterol levels.

METHODS

The serum levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), and low-density lipoprotein cholesterol (LDLC) were measured and the Mt5178 C/A genotypes determined in 110 Japanese men aged 41-66 (mean 52.3) years who had received medical checkups twice in the period 1999-2005. The longitudinal changes of TC, HDLC, and LDLC were calculated according to genotype.

RESULTS

The serum levels of TC at baseline and follow-up were significantly different, whereas those of HDLC and LDLC were not. The changes in HDLC differed significantly between the two Mt5178 C/A genotype groups, with the changes in HDLC level being significantly greater in the Mt5178A genotype group than in the Mt5178C group (p = 0.015).

CONCLUSIONS

The Mt5178 C/A genotype may modify longitudinal changes in serum TC and HDLC levels in middle-aged Japanese men.

Joint effect of longevity-associated mitochondrial DNA 5178 C/A polymorphism and alcohol consumption on risk of hyper-LDL cholesterolemia in middle-aged Japanese men

BACKGROUND

Combined effects between mitochondrial DNA 5178 (Mt5178) C/A polymorphism and alcohol consumption on the risk of hypertension or hyperuricemia have been reported. The objective of this study was to investigate whether Mt5178 C/A polymorphism modulates the effects of alcohol consumption on the risk of dyslipidemia.

METHODS

A total of 394 male subjects 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 effect of Mt5178 polymorphism and alcohol consumption on the risk of dyslipidemia was conducted.

RESULTS

For men with Mt5178C, alcohol consumption was significantly and negatively associated with the risk of hyper-low-density lipoprotein (LDL) cholesterolemia (serum LDL cholesterol ≥ 140 mg/dl) (P for trend = 0.015). After adjustment for age, body mass index (BMI), habitual smoking, coffee consumption and use of antihypertensive medicine, the odds ratio (OR) for hyper-LDL cholesterolemia was significantly lower in daily drinkers with Mt5178C than non-drinkers with Mt5178C (OR = 0.360, 95% confidence intervals: 0.153-0.847). A significant and negative association between alcohol consumption and serum LDL cholesterol levels was also observed in Mt5178C genotypic men (P for trend < 0.01). On the other hand, the association between Mt5178A genotype and risk of hyper-LDL cholesterolemia does not appear to depend on alcohol consumption.

CONCLUSIONS

For Mt5178C genotypic men, alcohol consumption may reduce the risk of hyper-LDL cholesterolemia.

General consumer awareness of warnings regarding the consumption of alcoholic beverages

Over the past two decades, the liquor industry in Japan has strived to address alcohol-related problems through initiatives such as warnings in the various media. In this study, we conducted an Internet-based questionnaire survey to examine general consumer awareness of such warnings, and the media by which they are conveyed, on the consumption of alcoholic beverages. A total of 985 subjects (males: 487, females: 498) in age groups ranging from 20s to 70s responded (response rate: 22.4%). The awareness rates for warnings regarding underage drinking, drunk driving, and drinking during pregnancy, and those for messages encouraging moderation in drinking, were 96.4%, 83.7%, 59.6%, and 45.5%, respectively. Logistic regression analysis adjusted for habitual alcohol consumption demonstrated significant gender- and/or age-based differences in the rates of awareness of warnings and the media publicizing them. For example, the odds ratio of awareness among women of warnings against underage drinking was significantly higher than that of awareness among men. Issues that must be addressed in the future include:(1) increasing public awareness about messages regarding drinking during pregnancy and drinking in moderation;(2) reviewing the wording of warnings to make them more effective;and (3) devising and employing, on a regular basis, more effective means of transmitting messages in consideration of gender and age.

Relationship of body mass index to percent body fat and waist circumference among schoolchildren in Japan--the influence of gender and obesity: a population-based cross-sectional study

Background

Although the correlation coefficient between body mass index (BMI) and percent body fat (%BF) or waist circumference (WC) has been reported, studies conducted among population-based schoolchildren to date have been limited in Japan, where %BF and WC are not usually measured in annual health examinations at elementary schools or junior high schools. The aim of the present study was to investigate the relationship of BMI to %BF and WC and to examine the influence of gender and obesity on these relationships among Japanese schoolchildren.

Methods

Subjects included 3,750 schoolchildren from the fourth and seventh grade in Ina-town, Saitama Prefecture, Japan between 2004 and 2008. Information about subject's age, sex, height, weight, %BF, and WC was collected from annual physical examinations. %BF was measured with a bipedal biometrical impedance analysis device. Obesity was defined by the following two criteria: the obese definition of the Centers for Disease Control and Prevention, and the definition of obesity for Japanese children. Pearson's correlation coefficients between BMI and %BF or WC were calculated separately for sex.

Results

Among fourth graders, the correlation coefficients between BMI and %BF were 0.74 for boys and 0.97 for girls, whereas those between BMI and WC were 0.94 for boys and 0.90 for girls. Similar results were observed in the analysis of seventh graders. The correlation coefficient between BMI and %BF varied by physique (obese or non-obese), with weaker correlations among the obese regardless of the definition of obesity; most correlation coefficients among obese boys were less than 0.5, whereas most correlations among obese girls were more than 0.7. On the other hand, the correlation coefficients between BMI and WC were more than 0.8 among boys and almost all coefficients were more than 0.7 among girls, regardless of physique.

Conclusions

BMI was positively correlated with %BF and WC among Japanese schoolchildren. The correlations could be influenced by obesity as well as by gender. Accordingly, it is essential to consider gender and obesity when using BMI as a surrogate for %BF and WC for epidemiological use.

High blood pressure in obese and nonobese Japanese children: blood pressure measurement is necessary even in nonobese Japanese children

Background

Although the prevalences of obesity and hypertension (HT) are increasing in children, there have been few epidemiological studies of HT in Japanese children. We evaluated the prevalences of HT and high-normal blood pressure (HNBP), and examined the relationship between blood pressure (BP) and body mass index (BMI), in Japanese children.

Methods

The subjects of this study were 2420 children living in the town of Ina, Saitama Prefecture, Japan during the period from 2006 through 2008. Body height, weight, and BP were measured. HT and HNBP were defined according to the HT criteria for Japanese children. Children with HNBP or HT were defined as having high blood pressure (HBP).

Results

The prevalences of HBP were 15.9% and 15.8% in fourth-grade boys and girls, respectively, and 11.1% and 10.8% in seventh-grade boys and girls, respectively. Irrespective of sex or grade level, a higher BMI was associated with a higher prevalence of HBP (P < 0.001). When compared with the <50th percentile BMI category, the crude odds ratios (ORs) were statistically significant for the 75th to 84th percentile category in fourth-grade boys (OR: 4.54, 95% CI: 2.36–8.76), the ≥95th percentile in fourth-grade girls (13.29, 5.93–29.77), the 85th to 94th percentile (3.16, 1.46–6.84) in seventh-grade boys, and the ≥95th percentile (7.96, 3.18–19.93) in seventh-grade girls.

Conclusions

BMI was associated with HBP in Japanese school children. In addition, some children in the lower BMI categories also had HBP.

Combined effect of longevity-associated mitochondrial DNA 5178 C/A polymorphism and coffee consumption on the risk of hyper-LDL cholesterolemia in middle-aged Japanese men

The objective of this study was to investigate whether the mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism modifies the effects of coffee consumption on serum lipid levels and the risk of dyslipidemia in middle-aged Japanese men. A total of 397 male subjects (age, 53.9±7.8 years; mean±s.d.) were selected from among individuals visiting the hospital for regular medical check-ups. After adjustment for age, body mass index, habitual alcohol consumption, habitual smoking and use of antihypertensive medication, among subjects who consumed <1 cup of coffee per day, the odds ratio (OR) for hyper-low-density lipoprotein (LDL) cholesterolemia (serum LDL cholesterol > or =140 mg per 100 ml) was significantly lower in those with Mt5178A than in those with Mt5178C (OR=0.378, 95% confidence interval: 0.153-0.919). After adjustment, the association between the Mt5178A genotype and hyper-LDL cholesterolemia depended on coffee consumption (P for trend=0.018). Coffee consumption was positively associated with serum LDL cholesterol levels only in subjects with Mt5178A. However, in subjects with Mt5178C, serum LDL cholesterol level or risk of hyper-LDL cholesterolemia did not seem to depend on coffee consumption. These results suggest that for men with Mt5178A, coffee consumption negates the genetic benefit of lower risk for hyper-LDL cholesterolemia.

Longevity-associated NADH dehydrogenase subunit-2 237 Leu/Met polymorphism modulates the effects of daily alcohol drinking on yearly changes in serum total and LDL cholesterol in Japanese men

Reduced nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism, is reportedly associated with longevity in the Japanese population. The ND2-237Met genotype may exert resistance to atherogenic diseases, such as myocardial infarction or cerebrovascular disorders. To investigate whether ND2-237 Leu/Met polymorphism is associated with yearly changes in serum lipid levels, we conducted a longitudinal study of 107 healthy Japanese male subjects. Analysis of covariance revealed that the interaction between the ND2-237 Leu/Met genotypes and habitual drinking was significantly associated with yearly changes in serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDLC) levels (p=0.036 and p=0.006, respectively). In multiple regression analysis, daily drinking was significantly and positively associated with yearly changes in serum LDLC levels in men with ND2-237Met (p=0.026). After adjusting for covariates, yearly changes in serum LDLC levels were significantly lower in non-daily drinkers with ND2-237Met than in those with ND2-237Leu (p=0.047). These results suggest that ND2-237Met has a beneficial impact on yearly changes in serum LDLC in non-daily drinkers but not in daily drinkers.

Blue Monday phenomenon among men: suicide deaths in Japan

The number of suicide deaths in Japan has continued to be high, and is a pressing social problem. Although the weekly distribution of suicide deaths has been documented, no nationwide analysis has yet been conducted. In the present study, the ratios of the number of suicide deaths per day, by day of the week, and on weekdays relative to holidays were calculated using the data for all suicide deaths recorded in 2003. The suicide deaths recorded on holidays were treated as the reference, and a confidence interval of 95% (95% CI) was used. We calculated the suicide death ratios among men and women of all ages (men:23,396, women:8,713, total:32,109) and also among those of productive age (age:15-64 years, men:18,552, women:5,481, total:24,033). Among men of all ages, the suicide death ratio on Mondays was found to be significantly high at 1.49 (95% CI:1.04-2.14), and the ratios were found to decrease over the course of the week from Monday to Friday. On each weekday, the suicide death ratios among men of productive age were found to be higher than those among men of all ages. Among women, the suicide death ratios on any weekday were found to be higher than 1, but there was no significant difference between the days. Among both men and women, the number of suicide deaths on holidays was lower than that on weekdays. This study revealed that the number of suicide deaths recorded per day on Mondays is 1.5 times higher than that on holidays among men. This suggests that the structure of the work week may possibly influence suicide deaths among men. Future discussions regarding the arrangement and distribution of weekly holidays should be conducted in order to reduce the number of suicide deaths.

Usage of the .9 codes of the ICD-10 for Japanese mortality statistics

The structural deficits and problems associated with application of the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) were investigated. For this purpose, mortality statistics in Japan were examined for bias in the proportions of death causes classified using the ICD-10 four-character subcategory system, particularly the large distribution of cases classified under the .9 (unspecified) codes. The results showed that most deaths due to the 3 major causes were coded into the .9 subcategories. For example, 97.6% of the 607,065 deaths between 1995 and 2007 classified as I21 (acute myocardial infarction) were coded as I21.9 (acute myocardial infarction, unspecified). This suggests that the quality of the data recorded on many death certificates is poor. Thus, to ensure that the fourth-digit-level subcategories of the ICD-10 code system are effectively used to represent mortality data and actual causes of death in Japan, future studies should address the following objectives:(1) to minimize the discrepancy between the ICD classification terms and the names of diseases actually used in clinical practice, and (2) to actively raise awareness among physicians about the need to accurately record death causes on death certificates, since these records form the basis for determining mortality statistics in Japan.

NADH dehydrogenase subunit-2 237 Leu/Met polymorphism modulates the effects of coffee consumption on the risk of hypertension in middle-aged Japanese men

Background

Habitual coffee consumption has been reported to lower blood pressure in the Japanese population. The NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity and modifies the effects of alcohol consumption on blood pressure in the Japanese population. The objective of this study was to determine whether this polymorphism also modifies the effects of coffee consumption on blood pressure or the risk of hypertension in middle-aged Japanese men.

Methods

A total of 398 men (mean age ± standard deviation, 53.8 ± 7.8 years) were selected from among individuals visiting the hospital for regular medical check-ups. Hypertension was defined as a systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or antihypertensive drug treatment. Polymerase chain reaction-restriction fragment length polymorphism using the restriction enzyme AluI was performed to determine ND2-237 Leu/Met genotype.

Results

In subjects with ND2-237Leu, coffee consumption was significantly and negatively associated with diastolic blood pressure (P = 0.007). The odds ratio (OR) for hypertension was significantly lower in subjects with ND2-237Leu who consumed 2 or 3 cups of coffee per day than in those who consumed less than 1 cup of coffee per day (OR, 0.517; 95% confidence interval [CI], 0.276 to 0.968; P = 0.039). After adjustment, the OR remained significant (OR = 0.399; 95% CI, 0.184 to 0.869; P = 0.020). Moreover, after adjustment, the OR was significantly lower in subjects with ND2-237Leu who consumed more than 4 cups of coffee per day than in those who consumed less than 1 cup of coffee per day (OR, 0.246; 95% CI, 0.062 to 0.975; P = 0.046). However, the association between ND2-237Met genotype and hypertension did not depend on coffee consumption.

Conclusions

The present results suggest that the ND2-237 Leu/Met polymorphism modulates the effects of coffee consumption on hypertension risk in middle-aged Japanese men.

Changes in body mass index, leptin and adiponectin in Japanese children during a three-year follow-up period: a population-based cohort study

Objective

The study examined changes in and relationship between body mass index (BMI), leptin and adiponectin levels over a 3-year period in a pediatric population-based cohort.

Study design

A 3-year prospective cohort study of 268 boys and 251 girls aged 9–10 in Ina, Saitama, Japan.

Results

Median body mass index (BMI) significantly increased from baseline (age 9–10) to follow up (age 12–13) in boys from 17.1 to 18.3 kg/m² (P < 0.001) and in girls from 16.5 to 18.5 kg/m² (P < 0.001), respectively. Adiponectin values significantly decreased from baseline to follow up in boys (13.5 to 8.9 μg/ml, respectively) (P < 0.001) and in girls (12.4 to 9.5 μg/ml, respectively) (P < 0.001). Leptin values at follow up significantly decreased from baseline in boys (4.9 to 2.3 ng/dl, respectively) (P < 0.001) and also in girls (5.3 to 5.1 ng/dl, respectively) (P = 0.049).

A relatively strong correlation was seen in BMI (Spearman's correlation coefficient, r = 0.864, P < 0.001 in boys; r = 0.873, P < 0.001 in girls), adiponectin (r = 0.705, P < 0.001 in boys; r = 0.695, P < 0.001 in girls), and leptin (r = 0.449, P < 0.001 in boys; r = 0.610, P < 0.001 in girls) before and after the three-year period.

The ratio of follow up to baseline BMI was negatively correlated with that for adiponectin (r = -0.224, P < 0.001 in boys; r = -0.165, P = 0.001 in girls) and positively correlated with that for leptin (r = 0.518, P < 0.001 in boys; r = 0.609, P < 0.001 in girls).

Conclusion

This study demonstrated that baseline adiponectin, leptin and BMI values measured at ages 9–10 correlated with those measured three years later. However, adiponectin values decreased and leptin values increased in those subjects whose BMI increased during over this period.

Attitudes of Japanese medical students towards disclosure of a diagnosis of life-threatening illness

In this study we investigated the attitudes of Japanese medical students toward being informed of a diagnosis of life-threatening illness. Fourth-year medical students from 20 randomly sampled universities were administered questionnaires that examined their opinion about whether they would welcome disclosure of medical information if they were diagnosed as having an ultimately fatal disease. Data from 1,619 students (male 1,074, female 545, effective collection rate 90.6%) were analyzed. With regard to attitudes about disclosure of a diagnosis of life-threatening illness, 87.7% of the students stated that they would wish to be informed even if there was little chance of recovery, and 11.6% expressed a wish to be informed of their condition only if there was a chance of recovery. Students who did not wish to be informed even if there was a chance of recovery accounted for 0.7% of those surveyed. Our study reveals that medical students are more positive than are members of the general population with regard to being informed of the truth. The proportion of those who wished to be informed even if there was little chance of recovery was higher among students from national and public universities than among those from private universities, and the inter-group difference was statistically significant. Among male students, answers to the survey were significantly correlated with 12-item General Health Questionnaire scores and mental health status, suggesting that mental health status may have affected how this study population viewed being informed of their diagnosis.

NADH dehydrogenase subunit-2 237 Leu/Met polymorphism modifies the effects of alcohol consumption on risk for hypertension in middle-aged Japanese men

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity in the Japanese population, and the ND2-237Met genotype may exert antiatherogenic effects. To investigate whether ND2-237 Leu/Met polymorphism is associated with risk of hypertension, we conducted a cross-sectional study of 398 Japanese male subjects. The frequency of hypertension was significantly higher in ND2-237Leu genotypic men than in ND2-237Met genotypic men. On analysis of covariance, the interaction between ND2-237 Leu/Met polymorphism and habitual drinking was significantly associated with both systolic blood pressure and diastolic blood pressure. Multiple logistic regression analysis revealed that the ND2-237Met genotype, particularly in younger subjects (age <60 years), had a lower odds ratio for hypertension than the ND2-237Leu genotype. Moreover, the association of ND2-237 Leu/Met polymorphism with hypertension may depend on the frequency of alcohol consumption. The odds ratio for hypertension was significantly higher in daily drinkers with ND2-237Leu when compared with non- or ex-drinkers with ND2-237Leu. However, the association between the ND2-237Met genotype and hypertension may not depend on the frequency of alcohol consumption. The present results suggest that ND2-237 Leu/Met polymorphism is associated with hypertension and that modification of hypertension risk is dependent on alcohol consumption in middle-aged Japanese men.

Longevity-associated mitochondrial DNA 5178 C/A polymorphism and its interaction with cigarette consumption are associated with pulmonary function in middle-aged Japanese men

Pulmonary function is a crucial factor associated with longevity. Mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism is reported to be associated with longevity in the Japanese population. We have previously reported that Mt5178 C/A polymorphism is widely associated with physiological and biochemical status. The objective of this study was to investigate whether Mt5178 C/A polymorphism is associated with pulmonary function. The subjects were 463 Japanese men (mean age +/- SD 54.0 +/- 7.6 years). Genotyping of Mt5178 C/A was performed by polymerase chain reaction-restriction fragment length polymorphism. A cross-sectional study of the relationship between genotype and spirometric data, namely forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV(1)), was conducted. Among younger subjects (age <55 years), FVC and FEV(1) were significantly higher for men with Mt5178A than for those with Mt5178C. Interaction between Mt5178 C/A polymorphism and smoking habits in FEV(1)/FVC ratio was observed. Cigarette consumption (pack-years of smoking) was significantly and negatively associated with FEV(1)/FVC ratio for men with Mt5178C. Among older subjects (age >or=55 years), FEV(1)/FVC ratio was significantly lower for current smokers with Mt5178C than for never smokers with Mt5178C or for never smokers with Mt5178A. Mt5178 C/A polymorphism and its interaction with cigarette consumption may be associated with pulmonary function in Japanese men.

Longevity-associated NADH dehydrogenase subunit-2 237 Leu/Met polymorphism influences the effects of alcohol consumption on serum uric acid levels in nonobese Japanese men

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is reportedly associated with longevity in the Japanese population. The ND2-237Met genotype may confer resistance to cardiovascular and cerebrovascular atherogenic diseases. Hyperuricemia is one of the risk factors for cardiovascular disease. To investigate whether ND2-237 Leu/Met polymorphism is associated with serum uric acid (SUA) levels, we conducted a cross-sectional study in 321 healthy Japanese male subjects. In nonobese (body mass index, BMI<25) male subjects, interaction between ND2-237 Leu/Met genotypes and drinking frequency on SUA levels was observed (P=0.031). The SUA levels were significantly higher in daily drinkers with ND2-237Leu than in non-daily drinkers with ND2-237Leu (P=0.018). In nonobese men, after adjustment for covariates, daily drinkers with ND2-237Leu had a significantly higher odds ratio (OR) for hyperuricemia (SUA> or =6.5 mg/dl: vs. daily drinkers with ND2-237Met, OR=3.26, 95% confidence interval (CI) 1.14-9.29; vs. non-daily drinkers with ND2-237Leu, OR=3.22, 95% CI 1.39-7.45; SUA> or =7.0 mg/dl: vs. non-daily drinkers with ND2-237Met, OR=3.53, 95% CI 1.00-12.4). However, in obese (BMI> or =25) men, no significant interaction between ND2-237 Leu/Met polymorphism and habitual drinking on SUA levels or on the risk for hyperuricemia was observed. These results suggest that ND2-237 Leu/Met polymorphism modulates the effects of daily alcohol consumption on SUA levels in nonobese Japanese men.