Masao Yoshida

Association of Life-style with Intraocular Pressure in Middle-aged and Older Japanese Residents

PURPOSEnTo evaluate the associations of several life-style-related factors with intraocular pressure (IOP).nnnMETHODSnOf a total of 649 men and women who had been examined in an annual health check-up being conducted by a general hospital in Ibaraki prefecture, Japan, 569 individuals (age range, 29-79 years) who had not undergone any medical treatment for hypertension, ocular hypertension, or glaucoma, were selected as the subjects of this study. The associations of several life-style-related factors with the IOP were evaluated by multiple regression analyses and analyses of covariance.nnnRESULTSnBody mass index (BMI), alcohol consumption score, and cigarette consumption were found to have a significantly positive association with the IOP in men (P for trend =.002, <.001, and <.001, respectively). In women also, the BMI was positively related to the IOP (P for trend =.071). In respect to the effects of coffee consumption, it was shown that in men the mean IOP adjusted for age, the BMI, alcohol intake score, cigarette consumption, and blood pressure were significantly lower in habitual coffee drinkers than in coffee abstainers (P =.016).nnnCONCLUSIONnThe results of this study suggest that the IOP level may be substantially affected by daily life-style among Japanese.

Age-specific prevalence of open-angle glaucoma and its relationship to refraction among more than 60,000 asymptomatic Japanese subjects

To clarify the prevalence of open-angle glaucoma (OAG) and its relationship to refraction among a Japanese population with a broad range of ages including children and adolescents, an 1-year epidemiological survey was conducted. The subjects of this study were 64,394 asymptomatic individuals who had attended the glasses and contact lens center in Yokohama, Japan from February 15, 1999 to February 14, 2000 and had been subjected to several optical examinations. The results of this study showed that the overall prevalence of OAG was 1.19% (1.14% for men, and 0.98% for women). Prevalence for children aged 6 to 14 of both sexes was approximately 0.5%. There were significant positive associations between the strength (diopter) of myopic refraction and OAG prevalence among all the examined subjects.

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

AbstractNADH 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≥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≥7.0 mg/dl: vs. non-daily drinkers with ND2-237Met, OR=3.53, 95% CI 1.00-12.4). However, in obese (BMI≥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.

Association of smoking with intraocular pressure in middle-aged and older Japanese residents

ObjectivesTo clarify whether smoking was associated with elevated intraocular pressure (IOP) and to evaluate the interrelationship among IOP, blood viscosity, and smoking.MethodsThis cross-sectional study analyzed health examination data obtained between 2001 and 2004 from 1113 individuals (829 men and 284 women), ranging in age from 28 to 79xa0years, who had not undergone any ocular surgery or medical treatment for hypertension, ocular hypertension, and glaucoma.ResultsMultiple-regression analysis showed that systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), and number of cigarettes smoked per day had a significantly positive association with IOP in men (Pxa0<xa00.05). In women also, SBP, DBP, and BMI were positively related to IOP (Pxa0<xa00.05). On the contrary, age had a significant negative association with IOP in both sexes (Pxa0<xa00.01). Analysis of covariance and multiple logistic regression analyses showed that the adjusted mean IOP and the multivariate odds ratios for IOP increased with increasing cigarette consumption in men (P for trendxa0=xa00.01 and 0.06, respectively). Analysis of covariance found that smoking was significantly associated with both high IOP and high hematocrit in men (P for trend <0.05); however, the adjusted mean IOP values were higher in smokers than in nonsmokers, regardless of the hematocrit level.ConclusionsThe results of this study suggested that the IOP level may be substantially affected by smoking habit in middle-aged and older 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

AbstractPulmonary 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 (FEV1), was conducted. Among younger subjects (age <55 years), FVC and FEV1 were significantly higher for men with Mt5178A than for those with Mt5178C. Interaction between Mt5178 C/A polymorphism and smoking habits in FEV1/FVC ratio was observed. Cigarette consumption (pack-years of smoking) was significantly and negatively associated with FEV1/FVC ratio for men with Mt5178C. Among older subjects (age ≥55 years), FEV1/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.

Association study of IGF1 polymorphisms with susceptibility to high myopia in a Japanese population

Purpose Polymorphisms in the insulin-like growth factor 1 (IGF1) gene were previously associated with high or extreme myopia in Caucasian and Chinese populations. In the present study, we investigated whether IGF1 polymorphisms are associated with high myopia in a Japanese population. Methods A total of 446 Japanese patients with high myopia (≤−9.00 diopters) and 481 Japanese healthy controls (+1.50 diopters to −1.50 diopters) were recruited. We genotyped seven tagging single-nucleotide polymorphisms (SNPs) in IGF1 and assessed allelic and haplotypic diversity in cases and controls. Results There were no statistically significant differences in the allele frequencies of IGF1 SNPs and genotypes between cases and controls (P>0.05). However, the A allele of rs5742629 and the G allele of rs12423791 were associated with a moderately increased risk of high myopia (odds ratio [OR] =1.20 and OR =1.21, respectively) with borderline statistical significance (P=0.0502, corrected P (Pc) =0.21 and P=0.064, Pc=0.29, respectively). The haplotype consisting of the A allele of rs5742629 and the G allele of rs12423791 was marginally associated with the risk of high myopia (P=0.041; OR =1.21); this association was not significant after correction (Pc=0.19). Conclusion We found that the IGF1 SNPs are not significantly associated with high myopia in our Japanese population. Our results are in contrast to a previous study in which extreme myopia cases had significantly higher frequencies of the G allele of rs5742629 and the C allele of rs12423791 than controls. Therefore, the IGF1 SNPs may not be important factors for susceptibility to high myopia in all populations. Further genetic studies are needed to elucidate the possible contributions of the IGF1 region to the development of high myopia.

Mitochondrial DNA 5178 C/A polymorphism modulates the effects of coffee consumption on elevated levels of serum liver enzymes in male Japanese health check-up examinees: an exploratory cross-sectional study

BackgroundLongevity-associated mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism modulates the effects of coffee consumption on the risk of hypertension, dyslipidemia, and abnormal glucose tolerance. The objective of this study was to investigate whether Mt5178 C/A polymorphism modifies the effects of coffee consumption on abnormally elevated levels of serum liver enzymes in male Japanese health check-up examinees.MethodsA total of 421 male subjects (mean ageu2009±u2009SD, 54.1u2009±u20097.7xa0years) 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 on elevated levels of serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), and serum gamma-glutamyl transpeptidase (GGT) was then conducted.ResultsFor men with Mt5178C, after adjustment for age, body mass index, alcohol consumption, habitual smoking, green tea consumption, antihypertensive treatment, and antidiabetic treatment, elevated levels of serum AST, as defined as ≥30xa0U/L; those of serum ALT, as defined as ≥25xa0U/L; or those of serum GGT, as defined as ≥60 or >51xa0U/L, may depend on coffee consumption (P for trendu2009=u20090.013, P for trend <0.001, P for trendu2009=u20090.002, and P for trend <0.001, respectively). On the other hand, no significant joint effects of Mt5178A genotype and coffee consumption on elevated levels of serum liver enzymes were observed.ConclusionsThe present results suggest that Mt5178 C/A polymorphism modifies the effects of coffee consumption on abnormally elevated levels of serum liver enzymes in male Japanese health check-up examinees.

Association of body mass index with risk of age-related cataracts in a middle-aged Japanese population: the JPHC Study

ObjectivesMany epidemiological studies have demonstrated that body mass index (BMI) is associated with the risk of developing age-related cataracts. These reports have suggested that high and low BMIs can affect the onset or progression of age-related visual impairment. However, few prospective studies have examined this relationship in a general Asian population. Therefore, in this study, we investigated whether BMI was associated with an increased risk of age-related cataracts by performing a 5-year prospective population-based study in a middle-aged Japanese population.MethodsThis 5-year population-based study included 35,365 men and 40,825 women (aged 45–74 years), who were recruited into the Japan Public Health Center (JPHC)-based Prospective Study and had not reported cataracts in a baseline survey. The self-reported diagnosis of age-related cataracts was used in the analysis of this study.ResultsAt follow up, 1,004 men (2.84%) and 1,807 women (4.43%) reported new diagnoses of age-related cataracts. The multivariate odds ratios (ORs) for those in the lowest and the highest BMI categories, compared with a BMI category of 21.0–22.9 as a reference point (OR, 1.00), were 1.29 [95% confidence interval (CI) 0.93–1.79] and 1.15 (95% CI 0.96–1.39) in men, and 1.23 (95% CI 0.97–1.55) and 1.19 (95% CI 1.04–1.36) in women.ConclusionsPrevious studies have suggested high BMI as a risk factor of age-related cataracts for Caucasian populations in developed countries while low BMI for populations living in developing countries. In contrast to those studies, the present large-cohort study showed a U-shaped association between BMI and the incidence of cataracts in Japanese men and women.