Rice-Based Diet and Cardiovascular Disease Mortality in Japan: From the Takayama Study.

Rice is the staple food in Japan and many other Asian countries, but research on rice-based diets and cardiovascular disease is limited. We aimed to evaluate the association between rice consumption as grain dishes and cardiovascular disease mortality in comparison with bread and noodle consumption. The subjects were 13,355 men and 15,724 women aged ≥35 years who enrolled in the Takayama Study. Diet intake was assessed using a validated food-frequency questionnaire. Causes of death were identified from death certificates. Cardiovascular disease was defined according to the International Classification of Diseases and Health Related Problems, 10th Revision (code I00-I99). Hazard ratios in the second, third, and highest quartiles versus the lowest quartile of rice intake for cardiovascular disease mortality were 0.98, 0.80, and 0.78 for men, respectively (trend p = 0.013), but no significant association was observed among women. Rice intake was positively correlated with the intake of soy products and seaweed, and negatively correlated with the intake of meat and eggs. Neither bread nor noodles were associated with cardiovascular disease mortality. In Japan, choosing rice as a grain dish is likely to be accompanied by healthier foods as side dishes, which may have a potential role in the prevention of cardiovascular disease.

Knowledge of Osteoporosis and Its Associated Factors among Public Health Professionals in a Municipal Office in Japan.

Lifelong efforts to maintain bone health are beneficial for preventing osteoporosis, and public health professionals play an important role in that. The current study aimed to assess the knowledge of osteoporosis among public health professionals in a Japanese municipal office and explored associated factors. A questionnaire was distributed to 124 eligible public health professionals in a municipal office in S City, Japan; in total, 89 individuals who returned it were analyzed. Their knowledge of osteoporosis was assessed using the revised Osteoporosis Knowledge Test, its two subscales, and the Facts on Osteoporosis Quiz, translated into Japanese. To compare the level of knowledge between categories of selected factors, the Wilcoxon rank-sum test or the Kruskal-Wallis test was applied. The mean of correct answers ranged from 70 to 79%, depending on the scale. The knowledge level was significantly higher among registered dietitians than among public health nurses. Higher scores were significantly associated with past learning experience in off-the-job training, with having a family history of osteoporosis, and with having had a past osteoporosis test. Japanese public health professionals were likely to have moderate knowledge of osteoporosis. Several factors were implied to be associated with the knowledge level of osteoporosis.

Associations of total nut and peanut intakes with all-cause and cause-specific mortality in a Japanese community: the Takayama study.

Numerous epidemiological studies have suggested that nut intake is associated with a reduced risk of mortality. Although diets and lifestyles differ by regions or races/ethnicities, few studies have investigated the associations among non-white, non-Western populations. We evaluated the associations of total nut and peanut intakes with all-cause and cause-specific mortality in a population-based prospective cohort in Japan. Participants (age: ≥35 years at baseline in 1992; n 31 552) were followed up until death or the end of follow-up in 2008. Those with cancer, CHD or stroke at baseline were excluded. Dietary intake was assessed only at baseline by using a validated FFQ. In total, 2901 men died during 183 299 person-years and 2438 women died during 227 054 person-years. The mean intakes of total nuts were 1·8 and 1·4 g/d in men and women, respectively. Although peanut intake accounted for approximately 80 % of the total nut intake, total nut and peanut intakes were inversely associated with all-cause mortality in men after adjusting for all potential confounders. For example, compared with the lowest quartile category, the adjusted hazard ratio (95 % CI) of total nut intake for all-cause mortality in men of the highest quartile category was 0·85 (95 % CI 0·75, 0·96) (Pfor trend = 0·034). Peanut intake was inversely associated with digestive disease mortality in men and CVD mortality in women. Total nut and peanut intakes, even in low amounts, were associated with a reduced risk of mortality particularly in men.

Associations Between Dietary Melatonin Intake and Total and Cause-Specific Mortality Among Japanese Adults in the Takayama Study.

Potential health benefits of melatonin have been suggested. Although melatonin is present in various foods, little is known about the health effects of dietary melatonin intake. We estimated habitual dietary melatonin intake and examined its association with total and cause-specific mortality in a population-based cohort study in Japan. Study subjects included 13,355 men and 15,724 women aged ≥35 years who responded to a self-administered questionnaire in 1992. Their diets were assessed via a food frequency questionnaire at baseline. The melatonin content in various foods on the questionnaire was measured to estimate melatonin intake. Mortality was ascertained during 16 years of follow-up (1992-2008). Hazard ratios (HRs) and 95% confidence intervals (CIs) for total and cause-specific mortality were calculated according to melatonin quartiles. A total of 5,339 deaths occurred during follow-up. Melatonin intake was significantly associated with decreased risks of total mortality, cardiovascular mortality, and noncancer, noncardiovascular mortality after controlling for covariates; HRs for the highest quartile of melatonin intake versus the lowest were 0.90 (95% CI: 0.82, 0.98; P for trend = 0.05), 0.85 (95% CI: 0.72, 0.99; P for trend = 0.10), and 0.77 (95% CI: 0.67, 0.90; P for trend = 0.003), respectively. The data suggest a potential benefit of dietary melatonin with regard to mortality rates.

Association Between Anger and Mortality in Women and Men: A Prospective Cohort Study in a Japanese Community.

Background: Anger is a common problem in society, and anger's relationship with mortality, in particular with cardiovascular mortality, has been studied mainly in male western population. There are no prospective studies in Japan, about the association between anger and mortality. Materials and Methods: This study examined the association of anger with all-cause and cause-specific mortality in a Japanese community. Data came from the Takayama Study, which recruited residents aged ≥35 years in 1992 from Takayama City in Gifu, Japan. The current study used information on anger that was obtained from the second survey in 2002. A total of 11,902 healthy participants aged ≥45 years completed a self-administered questionnaire. Anger was assessed using the Spielberger Trait Anger Scale. Results: The main causes of deaths during the follow-up period from 2002 to 2013 were 460 for neoplasm, 254 for cardiovascular, and 435 for other causes. After adjusting for potential confounders, we found a significant positive association between the trait anger score and the risk of cardiovascular mortality for women, with a hazard ratio for high versus low score of trait anger of 1.81 (95% confidence interval 0.91-3.63, p for trend = 0.04), but not for men. Conclusions: Data suggest that for Japanese women, high trait anger score may be associated with an increased risk of cardiovascular mortality. Potential gender differences in the association between trait anger and mortality should be further studied from the cultural context.

Effect of Dietary Nori (Dried Laver) on Blood Pressure in Young Japanese Children: An Intervention Study.

BACKGROUND: Few studies have examined the association between seaweed intake and blood pressure in children. We conducted an intervention study to investigate whether seaweed intake affects blood pressure. METHODS: Subjects were children aged 4 to 5 years attending a preschool in Aichi Prefecture, Japan, in 2010. Among 99 students, 89 (89.9%) were enrolled in our study. Nori (dried laver), an edible seaweed widely consumed in Japan, was used as a dietary intervention. Children in the intervention group were asked to consume 1.76 grams per day of roasted nori in addition to standard meals for 10 weeks. Children in the control group consumed their usual diet. Before the intervention and at the 10th week of the intervention, children's blood pressure was measured three times successively using an automated sphygmomanometer with subjects in a sitting position. Changes in systolic (SBP) and diastolic blood pressure (DBP) were compared between 55 children in the intervention group and 26 in the control group after adjustment for SBP and DBP before the intervention. RESULTS: Changes in SBP were -8.29 mm Hg in the intervention group and +0.50 mm Hg in the control group (P for difference in change = 0.051). Changes in DBP were -6.77 mm Hg in the intervention group and -0.05 mm Hg in the control group (P = 0.031). In girls, no difference in blood pressure changes was found between the intervention and control groups. CONCLUSION: Nori intake lowered DBP level in boys. Seaweed intake might have preventive effects on elevated blood pressure in childhood.

Effect of hypertriglyceridemia in dyslipidemia-induced impaired glucose tolerance and sex differences in dietary features associated with hypertriglyceridemia among the Japanese population: The Gifu Diabetes Study.

AIMS/INTRODUCTION: The mechanisms underlying hypertriglyceridemia-induced impaired glucose tolerance in Japanese individuals remain unclear. We aimed to evaluate the effect of hypertriglyceridemia on glucose metabolism in comparison with that of increased low-density lipoprotein or decreased high-density lipoprotein levels and to elucidate the sex differences in hypertriglyceridemia-related dietary intake among Japanese individuals. MATERIALS AND METHODS: We randomly selected 898 (384 men and 514 women) participants aged 40-78 years in the Gifu Diabetes Study; those taking medication for dyslipidemia or diabetes mellitus were excluded. Serum levels of glucose metabolism parameters and the food frequency were measured cross-sectionally. The glycated hemoglobin was measured again after 5 years. RESULTS: Glucose metabolism parameters and the percentage of individuals with impaired glucose tolerance were significantly higher in the high triglyceride group in men and women. Similar trends were observed in the low high-density lipoprotein group, but only in men. Meanwhile, only the homeostasis model assessment of insulin resistance was higher in the high low-density lipoprotein group. In non-obese men, the percentage of energy intake from alcohol per total daily energy intake was significantly greater in the high triglyceride group. In obese women, the total energy intake was significantly greater in the high triglyceride group. At the 5-year follow up, the risk of elevated glycated hemoglobin levels with hypertriglyceridemia was increased in men. CONCLUSIONS: Hypertriglyceridemia is a stronger risk factor for impaired glucose tolerance than increased low-density lipoprotein or decreased high-density lipoprotein. For dietary habits, increased daily alcohol energy intake in non-obese men and increased total energy intake in obese women were associated with hypertriglyceridemia.

Body mass index and mortality among middle-aged Japanese individuals with diagnosed diabetes: The Japan Public Health Center-based prospective study (JPHC study).

AIM: To examine the association between body mass index (BMI) and mortality among middle-aged people with diabetes in Japan. METHODS: A total of 3032 men and 1615 women, aged 40-69 years, with diabetes were analyzed. Cox proportional hazards models, adjusted for potential confounding factors, were used to estimate mortality hazard ratios (HRs) across BMI categories at the baseline. RESULTS: There were 1761 deaths during a mean follow-up period of 18.5 years. Increased all-cause mortality was observed at both ends of the BMI distribution; compared with the reference BMI category (23.0-24.9 kg/m2), the HRs were 1.25 (95% confidence interval [CI], 0.9997-1.56) in the lowest (14.0-18.9 kg/m2) and 1.36 (95% CI, 1.06-1.74) in the highest (30.0-39.9 kg/m2) categories (P = 0.001). Similar all-cause mortality trends were observed after excluding deaths within 3 years of follow-up, as well as for men and men who had ever smoked. While a similar non-linear pattern was observed for cancer-specific mortality, heart disease-specific mortality was only increased in the highest BMI category (HR, 1.86; 95% CI, 1.06-3.25). CONCLUSION: This population-based prospective study demonstrated increased all-cause mortality at both ends of the BMI distribution among Japanese people with diabetes.

Alcohol-induced impaired insulin secretion in a Japanese population: 5-year follow up in the Gifu Diabetes Study.

AIMS/INTRODUCTION: Although moderate alcohol consumption lowers the risk of type 2 diabetes in European populations, the same cannot be assumed for Japanese patients with diabetes related to low insulin secretion rather than resistance. We aimed to evaluate the effects of daily alcohol consumption on glucose tolerance and diabetes development risk in Japanese populations. MATERIALS AND METHODS: This retrospective study randomly enrolled 452 men and 659 women aged 40-78 years in 2005 (Gifu, Japan). The participants completed a 75-g oral glucose tolerance test and medical questionnaire. The homeostasis model assessment of insulin resistance, homeostasis model assessment of ß-cell function and insulinogenic index were used to estimate insulin sensitivity and secretion. The relationships between alcohol consumption and these parameters were analyzed using logistic regression after adjusting for potential confounders. The 5-year changes in hemoglobin A1c levels were also evaluated. RESULTS: The adjusted odds ratios for elevated homeostasis model assessment of ß-cell function values (<40%) in the 0-19.9 g/day, 20.0-39.9 g/day and ≥ 40 g/day alcohol consumption groups were 0.98, 1.46 and 2.68, respectively. Alcohol consumption induced a significant decrease in the insulin secretion level among the ≥40 g/day drinkers, especially in men. However, there was no risk of increased insulin resistance based on the homeostasis model assessment of insulin resistance (<2.5) results. The 5-year risk of elevated hemoglobin A1c levels (≥6.5%) was increased according to increase in alcohol consumption in both men and women. CONCLUSIONS: Daily alcohol consumption was associated with reduced insulin secretion and an increased diabetes development risk in Japanese populations.

Passive smoking and type 2 diabetes among never-smoking women: The Japan Public Health Center-based Prospective Study.

AIMS/INTRODUCTION: The aim of the current study was to prospectively evaluate the association between passive smoking from a spouse and the risk of diabetes among never-smoking Japanese women. Passive smoking at a workplace (or public facilities) was assessed as a secondary measure. MATERIALS AND METHODS: In the Japan Public Health Center-based Prospective Study (baseline 1990 or 1993), we followed 25,391 never-smoking women aged 40-69 years and without diabetes. Passive smoking was defined as having a husband who was a self-reported smoker, and the exposure at a workplace (or public facilities) was self-reported by women. The development of diabetes was identified in questionnaires administered at the 5-year and 10-year surveys. A pooled logistic regression model was used to assess the association between passive smoking and the development of diabetes with adjustment for age and possible confounders. RESULTS: Compared with women whose husbands had never smoked, women whose husband smoked ≥40 cigarettes/day had significantly higher odds of developing diabetes in an age-adjusted model, but the association was attenuated in a multivariable model (odds ratio 1.34, 95% confidence interval 0.96-1.87). There was a dose-response trend between the number of cigarettes smoked by a husband and the odds of developing diabetes (P = 0.02). Women reporting daily passive smoking at a workplace (or public facilities) had higher odds of developing diabetes than women reporting no such exposure (odds ratio 1.23, 95% confidence interval 0.995-1.53). CONCLUSIONS: Our results indicated a higher risk of diabetes among never-smoking Japanese women with higher exposure to passive smoking from a spouse.

High Intake of Free Sugars, Fructose, and Sucrose Is Associated with Weight Gain in Japanese Men.

BACKGROUND: Available evidence for associations between sugar intake and body weight is largely from short-term controlled trials and studies focusing on sugar-sweetened beverages. Studies on long-term weight change related to the intake of types of sugar are thus needed. OBJECTIVE: We examined the associations between weight change and the intake of various types of carbohydrates, including starch, total sugars, and free or naturally occurring sugars and saccharides (i.e., glucose, fructose, sucrose, and lactose), among Japanese men and women. METHODS: This prospective cohort study included 14,971 residents of Takayama City in Japan who were aged 35-69 y at the first survey in 1992 and responded to a self-administrated questionnaire at the second survey in 2002. We excluded those with cancer, coronary artery disease, stroke, or diabetes on the first survey and those with missing information about body weight on both surveys, leaving 13,229 participants for analysis (5879 men and 7350 women). Mean (95% CI) values of 10-y weight change according to types of carbohydrates were estimated using linear regression models with adjustment for total energy intake and other dietary and lifestyle factors. Dietary intake was assessed at the first survey using a validated FFQ. RESULTS: Among men, free sugar intake was associated with weight gain and the estimated means (95% CIs) of weight change were -0.60 (-0.67, -0.54), -0.31 (-0.38, -0.24), -0.12 (-0.19, -0.05), and 0.20 (0.13, 0.27) kg from the first to fourth quartiles (P-trend = 0.002). Moreover, high intakes of sucrose and fructose were associated with weight gain (P-trend: 0.018 for sucrose and 0.001 for fructose). Among women, the intake of any type of carbohydrate was not significantly associated with weight change. CONCLUSIONS: These results suggested that high intakes of free sugars, sucrose, and fructose were associated with long-term weight gain among Japanese men.

Knowledge of diabetes and its determinants: a cross-sectional study among adults in a Japanese community.

OBJECTIVE: To assess general knowledge of diabetes and its determinants among adult men and women in a Japanese community. SETTING: A cross-sectional study with the residential registry in Gifu City. Blood tests were conducted to measure fasting blood glucose levels and the levels after 2 hours of a 75-gram oral glucose load. Participants' previous diagnosis of diabetes and demographic status were identified from a questionnaire. A validated food frequency questionnaire was also administered. To assess the association between good knowledge of diabetes and the level of each factor, a logistic regression was utilised with adjustments for age, education and parental history of diabetes. PARTICIPANTS: A total of 1019 men and women aged 40-78 years. PRIMARY OUTCOME MEASURE: The Diabetes Knowledge Questionnaire was administered. Participants with ≥75% of answers correct were defined as having a good knowledge of diabetes. RESULTS: Previous diagnosis of diabetes was significantly associated with good knowledge of diabetes (OR=2.36; 95% CI 1.19 to 4.68). Among individuals with no previous diagnosis of diabetes, age ≥60 years (OR=0.55; 95% CI 0.36 to 0.86, p value for trend=0.02) and education <12 years (OR=0.54; 95% CI 0.30 to 0.97) were significantly associated with low knowledge of diabetes. The highest tertile intakes of green-yellow vegetables (OR=1.77; 95% CI 1.07 to 2.91, p value for trend=0.03) and seafood (OR=1.76; 95% CI 1.04 to 2.95, p value for trend=0.03) were associated with high knowledge of diabetes. CONCLUSIONS: Some diabetes risk factors were implied to determine the general knowledge of diabetes. Conducting further studies of knowledge in various populations is warranted.

Changes in oxidative stress levels during two weeks of smoking cessation treatment and their association with nutritional characteristics in Japanese smokers.

Although several experimental studies have reported that oxidative stress levels decrease during smoking cessation, how they change among general smokers has yet to be completely elucidated. In the present study, a total of 23 smokers who underwent smoking cessation treatment were observed for two-week changes in their levels of 8-OHdG and 8-isoprostane. Physical and nutritional characteristics were measured at the initial patient visit, and casual urine samples were collected at the initial visit and at a follow-up visit two weeks later. Oxidative stress was measured by a high performance liquid chromatography electrochemical detector, and the two-week difference in the levels of oxidative stress was assessed according to demographic and nutrient factors. Neither the urinary level of 8-OHdG nor that of 8-isoprostane decreased, although the cotinine level was decreased at two weeks. A Two-way repeated ANOVA revealed a significant interaction for fat intake by time for the change in the 8-OHdG level (P=0.03) and significant interactions for α-tocopherol intake (P=0.03), iron intake, and carbohydrate intake (P=0.03), all of which were time-dependent for the change in the 8-isoprostane level. The 8-OHdG level decreased among smokers with a high fat intake and was increased with a low fat intake. The 8-isoprostane levels were decreased among smokers with a high carbohydrate intake and increased with a low carbohydrate intake, decreased with a low iron intake and increased with a high iron intake and decreased with a low α-tocopherol intake and increased with a high α-tocopherol intake. Although the present study failed to observe a decrease in oxidative stress levels during the two-week smoking cessation period, we hypothesize that the intake levels of specific nutrients when initiating smoking cessation treatment may predict any subsequent changes in the oxidative stress levels.

Green tea intake and colorectal cancer risk in Japan: the Takayama study.

BACKGROUND: Reportedly, green tea has a preventive effect against colorectal cancer in animal models. Nevertheless, results from epidemiological studies of the association between green tea consumption and colorectal cancer have been inconsistent. We aimed to evaluate colorectal cancer risk in relation to green tea consumption in a population-based prospective cohort study. METHODS: Subjects were 13 957 men and 16 374 women aged ≥35 years in September 1992. The participants' green tea consumption was elicited by administering a food frequency questionnaire. The colorectal cancer incidence was confirmed through regional population-based cancer registries and histological identification from colonoscopy in two main hospitals in the study area. Colorectal cancer was defined as the sum of code C18 (colon cancer) and codes C19 and C20 (rectal cancer) according to ICD-10. RESULTS: Up to March 2008, 429 men and 343 women were diagnosed with colorectal cancer. No significant association was found between green tea consumption and colorectal cancer in men and women, respectively. However, for men, compared with the group of 'none or less than once per day' of green tea consumption, the multiple-adjusted relative risks (95% CIs) for colon cancer were 1.32 (0.90, 1.94), 0.76 (0.57, 1.02), and 0.78 (0.49, 1.22), respectively, in the group of 'once per day,' '2-3 times per day', and 'four times per day or more' (trend P = 0.045). CONCLUSIONS: This study observed no overall significant associations between green tea consumption and colorectal cancer risk, except that there was a weak trend for greater consumption of green tea with decreased risk of male colon cancer.

Association of Cervical Cancer Screening with Knowledge of Risk Factors, Access to Health Related Information, Health Profiles, and Health Competence Beliefs among Community-Dwelling Women in Japan

Objective: The aim of this study was to evaluate the past attendance for cervical cancer screening with knowledge of risk factors, access to health-related information, health profiles and health competence beliefs among Japanese women. Methods: Women ages 25, 30, 35, 40, 45, 50, 55, and 60 were contacted cross-sectionally as part of a project for the Japanese Ministry of Health, Labour and Welfare in Nikaho, Akita prefecture Japan between June 2010 and March 2011, and 249 women were analyzed for the current study. The questionnaire asked about past cervical cancer screening. Knowledge of each cervical cancer risk factor was determined on a four-point scale. A barriers to information access scale was utilized to assess the degree of difficulty in accessing health-related information. Health profiles were measured using the EuroQOL EQ-5D. Perceived health competence was measured using a scale (PHCS). The association was evaluated with odds ratios with 95% confidence interval were calculated from a logistic regression analysis after adjustment for age and potential confounders. The trend across the level was also assessed. Results: Women who knew that sexual intercourse at young age was a risk factor were significantly more likely to have participated in cervical cancer screening sometime in their lives (p for trend =0.02). Women who had pain/discomfort and those who had anxiety/depression were significantly more likely to have participated in cervical screening within the past two years (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.04­3.94; OR: 2.32, 95% CI: 1.05­5.16, respectively). Women with higher PHCS were significantly more likely to have attended for cervical screened at some point in their lives (p=0.04). Conclusion: This study observed that specific knowledge of cervical cancer risk factors, health profiles and PHCS were associated with the past attendance for cervical cancer screening among women in a community. Further researches are warranted.

Meat consumption and colorectal cancer risk in Japan: The Takayama study.

Compared with the abundant data from Western countries, evidence regarding meat consumption and colorectal cancer is limited in the Japanese population. We evaluated colorectal cancer risk in relation to meat consumption in a population-based prospective cohort study in Japan. Participants were 13 957 men and 16 374 women aged ≥35 years in September 1992. Meat intake, assessed with a validated food frequency questionnaire, was controlled for the total energy intake. The incidence of colorectal cancer was confirmed through regional population-based cancer registries and histological identification from colonoscopy in two main hospitals in the study area. From September 1992 to March 2008, 429 men and 343 women developed colorectal cancer. After adjustments for multiple confounders, a significantly increased relative risk of colorectal cancer was observed in the highest versus lowest quartile of the intake of total and red meat among men; the estimated hazard ratios were 1.36 (95% CI: 1.03, 1.79) for total meat (P for trend = 0.022), and 1.44 (95% CI: 1.10, 1.89) for red meat (P for trend = 0.009). A positive association between processed meat intake and colon cancer risk was also observed in men. There was no significant association between colorectal cancer and meat consumption in women. These results suggest that the intake of red and processed meat increases the risk of colorectal or colon cancer among Japanese men. Abstaining from excessive consumption of meat might be protective against developing colorectal cancer.

Factors associated with irregular breakfast consumption among high school students in a Japanese community.

BACKGROUND AND OBJECTIVES: This study evaluated the associations between the characteristics of high school students and irregular breakfast consumption and explored the association with knowledge regarding diet and dietary education in a community in Japan. METHODS AND STUDY DESIGN: A cross-sectional survey using a self-administered questionnaire was conducted in 2007 among all the high school students in the second grade in Imari, Saga. Data for 318 male and 292 female students were analyzed. Irregular breakfast consumption was defined as consuming breakfast three times or less in a week. The associations between the characteristics of students and irregular breakfast consumption were assessed using logistic regression with adjustments for sex and school. RESULTS: Among male students, a strong association between the consumption of juice or pop and irregular breakfast consumption was observed (OR comparing ">=2 servings" vs "rarely"=8.97, 95% CI=2.99-26.9). The associations with wake times and bed times were strong among male students, and the association with regular bowel movements was strong among female students. Students who had knowledge of regional agricultural and livestock products were more likely to consume breakfast regularly, and this association was significant among female students (OR=2.89, 95% CI=1.23-6.82). Significant associations were also observed with the consumption of snacks, and traditional greeting before meals. CONCLUSIONS: Several characteristics, including specific knowledge, were associated with the irregular consumption of breakfast. The results are of interest to policy makers, nutrition specialists, and educators working to enhance regular breakfast consumption among students.

Negative effect of a previous diagnosis of diabetes on quality of life in a Japanese population: The Gifu Diabetes Study.

OBJECTIVE: To evaluate the effect of a previous indication of hyperglycemia or previous diagnosis of diabetes on quality of life (QOL) in a randomly selected population from Gifu City, Japan. METHODS: In total, 452 males and 648 females were enrolled in this study. We collected information on previous indications of hyperglycemia and previous diagnoses of diabetes using a self-reported questionnaire. Participants also completed the World Health Organization Quality of Life-26 (WHOQOL-26) questionnaire and provided blood samples for the measurement of fasting plasma glucose and glycated hemoglobin levels. A 75-g oral glucose tolerance test was also performed. We compared QOL scores between the previous indication of hyperglycemia group and previous diagnosis of the diabetes group to those of the control group. RESULTS: WHOQOL-26 scores were significantly lower in the previous diagnosis of diabetes group than in the control group (3.23 ± 0.43 vs. 3.45 ± 0.43; p < 0.01). However, WHOQOL-26 scores in the previous indication of hyperglycemia group were not significantly different from those of the control group. Lowering of WHOQOL-26 scores was significantly affected by the previous diagnosis of diabetes not by the plasma glucose levels. CONCLUSIONS: Our study suggests that a previous diagnosis of diabetes has a negative effect on QOL in a Japanese population. Health promotion and education that take QOL into account should be considered for people diagnosed with diabetes.

Hemoglobin a1c levels and the risk of cardiovascular disease in people without known diabetes: a population-based cohort study in Japan.

High hemoglobin A1c (HbA1c) levels are strongly associated with an increased risk of cardiovascular disease (CVD) in people with and without diabetes. However, information regarding the relationship between low HbA1c levels and the risk of CVD among people without known diabetes is limited. The aim of this large-scale, prospective, population-based cohort study was to clarify the association between HbA1c levels and CVD risk among people without known diabetes.We followed-up 10,980 men and 18,079 women (46-80 years old and free of CVD and cancer at baseline) in the Japan Public Health Center-based Prospective Study. Using Cox models, we estimated the hazard ratios for CVD risk with adjustments for age, sex, geographic areas, body mass index, smoking status, sports and physical exercise, alcohol intake, systolic blood pressure, non-high-density lipoprotein cholesterol, and high-density lipoprotein cholesterol.During the median follow-up of 9.4 years, 935 CVD events (770 strokes and 165 coronary heart diseases) occurred. We observed a nonlinear association between HbA1c levels and CVD risk in participants without known diabetes. Compared with HbA1c levels of 5.0 to 5.4% (31-36 mmol/mol), the hazard ratios for CVD in participants without known diabetes were 1.50 (95% confidence interval: 1.15-1.95), 1.01 (0.85-1.20), 1.04 (0.82-1.32), and 1.77 (1.32-2.38) for HbA1c levels of <5.0% (<31 mmol/mol), 5.5 to 5.9% (37-41 mmol/mol), 6.0 to 6.4% (42-47 mmol/mol), and ≥6.5% (≥48 mmol/mol), respectively (P value for nonlinear trend: <0.001). In addition, the hazard ratio for CVD was 1.81 (1.43-2.29) in patients with known diabetes compared with participants with HbA1c levels of 5.0 to 5.4% and without known diabetes. This nonlinear relation persisted after excluding people with kidney dysfunction, liver dysfunction, anemia, body mass index <18.5 kg/m, or early events within 3 years of follow-up (P value for nonlinear trend: <0.01 for all tests).In conclusion, both low and high levels of HbA1c were associated with a higher risk of CVD in a Japanese general population without known diabetes.

Low-carbohydrate diet and type 2 diabetes risk in Japanese men and women: the Japan Public Health Center-Based Prospective Study.

OBJECTIVE: Evidence is sparse and contradictory regarding the association between low-carbohydrate diet score and type 2 diabetes risk, and no prospective study examined the association among Asians, who consume greater amount of carbohydrate. We prospectively investigated the association of low-carbohydrate diet score with type 2 diabetes risk. METHODS: Participants were 27,799 men and 36,875 women aged 45-75 years who participated in the second survey of the Japan Public Health Center-Based Prospective Study and who had no history of diabetes. Dietary intake was ascertained by using a validated food-frequency questionnaire, and low-carbohydrate diet score was calculated from total carbohydrate, fat, and protein intake. The scores for high animal protein and fat or for high plant protein and fat were also calculated. Odds ratios of self-reported, physician-diagnosed type 2 diabetes over 5-year were estimated by using logistic regression. RESULTS: During the 5-year period, 1191 new cases of type 2 diabetes were self-reported. Low-carbohydrate diet score for high total protein and fat was significantly associated with a decreased risk of type 2 diabetes in women (P for trend <0.001); the multivariable-adjusted odds ratio of type 2 diabetes for the highest quintile of the score were 0.63 (95% confidence interval 0.46-0.84), compared with those for the lowest quintile. Additional adjustment for dietary glycemic load attenuated the association (odds ratio 0.75, 95% confidence interval 0.45-1.25). When the score separated for animal and for plant protein and fat, the score for high animal protein and fat was inversely associated with type 2 diabetes in women, whereas the score for high plant protein and fat was not associated in both men and women. DISCUSSION: Low-carbohydrate diet was associated with decreased risk of type 2 diabetes in Japanese women and this association may be partly attributable to high intake of white rice. The association for animal-based and plant-based low-carbohydrate diet warrants further investigation.