Yutaka Takashima

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

PURPOSE To evaluate the associations of several life-style-related factors with intraocular pressure (IOP). METHODS Of 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. RESULTS Body 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). CONCLUSION The 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.

Longevity-associated mitochondrial DNA 5178 A/C polymorphism and blood pressure in the Japanese population.

It has been reported that the mitochondrial DNA 5178 adenine/cytosine (mt5178 A/C) polymorphism, also called NADH dehydrogenase subunit 2-237 methionine/leucine (ND2-237 Met/Leu) polymorphism, may be associated with longevity in Japanese individuals, and that the mt5178A genotype may have an antiatherogenic influence. To determine whether mt5178 A/C polymorphism influences blood pressure, we genotyped 412 healthy Japanese individuals and performed a cross-sectional study investigating the relationship between genotype and blood pressure. In women with mt5178A, the mean diastolic blood pressure was higher than in those with mt5178C by 3.2 mmHg (P=0.040). In men, no statistically significant difference in systolic or diastolic blood pressure was observed between mt5178 A/C genotypes. However, a significant correlation between mt5178 A/C genotypes and the effects of habitual drinking on blood pressure was found. After adjustment for several factors, in men carrying mt5178C, both systolic and diastolic blood pressure were significantly higher in daily drinkers than in occasional (P=0.002 and 0.002, respectively) as well as nondrinkers (P<0.001 and 0.001, respectively), whereas in men carrying mt5178A, no significant differences in blood pressure were detected, irrespective of alcohol consumption. These results suggest that mt5178 A/C (=ND2-237 Met/Leu) polymorphism may influence both diastolic blood pressure in Japanese women and the blood-pressure-increasing effect of drinking in Japanese men.

Longevity-associated mitochondrial DNA 5178 A/C polymorphism modulates effects of daily drinking and cigarette consumption on serum triglyceride levels in middle-aged Japanese men

Mitochondrial DNA 5178 adenine/cytosine (mt5178 A/C) polymorphism is one of the longevity-associated mitochondrial DNA polymorphisms. The frequency of the mt5178A genotype is significantly higher in Japanese centenarians than in the general population. We previously reported that serum high-density lipoprotein cholesterol levels were significantly higher in men with mt5178A than in those with mt5178C. However, this significant difference disappeared after adjusting for drinking frequency. To investigate the interaction between mt5178 A/C polymorphism and habitual drinking on serum lipid levels, we performed an association study in 321 healthy middle-aged Japanese men. Interaction between mt5178 A/C polymorphism and daily drinking on serum triglyceride (TG) levels was observed (P=0.019). Moreover, interaction between mt5178 A/C polymorphism and cigarette consumption on serum TG levels was also observed (P=0.022). Multiple regression analysis showed that, in men with mt5178A, daily drinking decreased TG levels (P=0.025), and cigarette consumption increased TG levels (P<0.001), while in men with mt5178C, the effects of daily drinking and cigarette consumption on TG levels were unclear. No interaction was observed on other lipid levels. Longevity-associated mitochondrial DNA 5178 A/C polymorphism thus influences the effects of daily drinking and cigarette consumption on TG levels in middle-aged Japanese men.

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

BackgroundMitochondrial DNA 5178 cytosine/adenosine (Mt5178 C/A) polymorphism is associated with longevity in the Japanese. The purpose of this study is to investigate whether Mt5178 C/A polymorphism modifies the effects of habitual smoking or habitual drinking on serum non-high-density lipoprotein (non-HDL) cholesterol levels in middle-aged Japanese men.MethodsA total of 394 male subjects (age 53.9 ± 7.9 years; mean ± SD) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effects of Mt5178 C/A polymorphism and cigarette smoking or alcohol drinking on serum non-HDL cholesterol levels was conducted. High levels of serum non-HDL cholesterol were defined as serum non-HDL cholesterol levels ≥160 mg/dl or ≥190 mg/dl.ResultsFor men with Mt5178A, cigarette smoking may increase serum non-HDL cholesterol levels (P for trend < 0.001), as well as the risk of high levels of non-HDL cholesterol (serum non-HDL cholesterol levels ≥160 mg/dl, P for trend < 0.001; serum non-HDL cholesterol levels ≥190 mg/dl, P for trend = 0.004). On the other hand, for men with Mt5178C, after adjusting for age and body mass index, alcohol consumption may decrease serum non-HDL cholesterol levels (P for trend = 0.043) and the risk of high levels of non-HDL cholesterol (serum non-HDL cholesterol level ≥160 mg/dl, P for trend = 0.005).ConclusionsThese gene-environment interactions on serum non-HDL cholesterol levels may contribute to the establishment of individualized prevention of the risk of high levels of serum non-HDL cholesterol.

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.

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.

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 ⩾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 mitochondrial DNA 5178 A/C polymorphism is associated with intraocular pressure in Japanese men.

Background: Mitochondrial DNA 5178 adenine/cytosine (mt5178 A/C) polymorphism has been reported to be associated with longevity in Japanese individuals, with experimental findings concluding that mt5178 A is an anti‐atherogenic genotype. The aim of this study was to determine whether mt5178 A/C polymorphism influences intraocular pressure (IOP), and its relationship with the development of arteriosclerosis.

Association of the longevity-associated mitochondrial DNA 5178 A/C polymorphism with serum protein fraction levels in healthy Japanese women

Mitochondrial DNA 5178 adenine/cytosine (mt5178 A/C) polymorphism was reported to be associated with longevity and susceptibility to adult-onset diseases in Japanese. To examine whether mt5178 A/C genotypes are associated with serum protein fraction profiles, we genotyped 461 healthy Japanese individuals, and studied the relationship of mt5178 A/C genotypes to both proportion and levels of serum protein fraction. The mt5178 A/C was genotyped using polymerase chain reaction-restriction fragment length polymorphism method. The alpha-1, alpha-2, and beta globulin proportions in females carrying mt5178A were significantly higher than those in females carrying mt5178C (P=0.002, 0.006, and 0.008, respectively). Moreover, the alpha-1, alpha-2, and beta globulin levels in females carrying mt5178A were significantly higher than those in females carrying mt5178C (P=0.001, 0.002, 0.018, respectively). This difference in globulin fraction level between the two genotypes was more evident in premenopausal females than in postmenopausal females. However, no such difference was found in males. These results provide the first evidence that the mt5178 A/C polymorphism may influence the serum protein fraction levels of the healthy Japanese women.