Koutatsu Maruyama

The joint impact on being overweight of self reported behaviours of eating quickly and eating until full: cross sectional survey.

Objective To examine whether eating until full or eating quickly or combinations of these eating behaviours are associated with being overweight. Design and participants Cross sectional survey. Setting Two communities in Japan. Participants 3287 adults (1122 men, 2165 women) aged 30-69 who participated in surveys on cardiovascular risk from 2003 to 2006. Main outcome measures Body mass index (overweight ≥25.0) and the dietary habits of eating until full (lifestyle questionnaire) and speed of eating (validated brief self administered questionnaire). Results 571 (50.9%) men and 1265 (58.4%) women self reported eating until full, and 523 (45.6%) men and 785 (36.3%) women self reported eating quickly. For both sexes the highest age adjusted mean values for height, weight, body mass index, and total energy intake were in the eating until full and eating quickly group compared with the not eating until full and not eating quickly group. The multivariable adjusted odds ratio of being overweight for eating until full was 2.00 (95% confidence interval 1.53 to 2.62) for men and 1.92 (1.53 to 2.40) for women and for eating quickly was 1.84 (1.42 to 2.38) for men and 2.09 (1.69 to 2.59) for women. The multivariable odds ratio of being overweight with both eating behaviours compared with neither was 3.13 (2.20 to 4.45) for men and 3.21 (2.41 to 4.29) for women. Conclusion Eating until full and eating quickly are associated with being overweight in Japanese men and women, and these eating behaviours combined may have a substantial impact on being overweight.

Fruit, vegetable and bean intake and mortality from cardiovascular disease among Japanese men and women: the JACC Study.

To examine the association of plant-based food intakes with CVD and total mortality among Japanese. In the Japan Collaborative Cohort Study for Evaluation of Cancer Risk, 25 206 men and 34 279 women aged 40-79 years, whose fruit, vegetable and bean intakes were assessed by questionnaire at baseline in 1988-90, were followed for 13 years. Deaths from total stroke, stroke subtypes, CHD and total CVD, according to the International Classification for Diseases 10th Revision, were registered. During 756 054 person-years of follow-up, there were 559 deaths from total stroke, 258 from CHD, 1207 from total CVD and 4514 from total mortality for men, and for women, 494, 194, 1036 and 3092, respectively. Fruit intake was inversely associated with mortality from total stroke (the multivariable hazard ratio (HR (95 % CI)) in the highest v. lowest quartiles = 0.67 (0.55, 0.81)), total CVD (HR = 0.75 (0.66, 0.85)) and total mortality (HR = 0.86 (0.80, 0.92)). Vegetable intake was inversely associated with total CVD (HR = 0.88 (0.78, 0.99)). Bean intake was inversely associated with other CVD (HR = 0.79 (0.64, 0.98)), total CVD (HR = 0.84 (0.74, 0.95)) and total mortality (HR = 0.90 (0.84, 0.96)). Further adjustment for other plant-based foods did not alter the association of fruit intake with mortality from total stroke, total CVD and total mortality, but attenuated the associations of vegetables and beans with mortality risk. In conclusion, intakes of plant-based foods, particularly fruit intake, were associated with reduced mortality from CVD and all causes among Japanese men and women.

Sleep-related intermittent hypoxemia and glucose intolerance: a community-based study.

BACKGROUND Intermittent hypoxemia is a fundamental pathophysiological consequence of sleep-disordered breathing and may alter glucose metabolism. To characterize the association between sleep-related intermittent hypoxemia and glucose metabolism, overnight pulse-oximetry and an oral glucose tolerance test were completed in a cohort of middle-aged and older Japanese adults. METHODS The study sample consisted of 1836 community-dwelling Japanese (age, 30-79 years; women, 65.5%; mean body mass index, 23.1 kg/m(2)). The oxygen desaturation index (ODI) was quantified during sleep using a ≥3% oxygen desaturation threshold and categorized as normal (<5.0 events/h), mild (5.0-15.0 events/h), and moderate to severe (≥15.0 events/h). The independent associations between the ODI and the prevalence of impaired fasting glucose, impaired glucose tolerance, diabetes, and two metrics of insulin resistance [homeostasis model assessment index for insulin resistance (HOMA-IR) and Matsuda index] were examined. RESULTS Compared with subjects with an ODI < 5 events/h, the adjusted odds ratio for prevalent impaired fasting glucose, glucose intolerance, and diabetes for subjects with an ODI ≥15.0 events/h were 1.27 (95% confidence interval, 0.72-2.23), 1.69 (1.03-2.76), and 1.28 (0.59-2.79), respectively. Both HOMA-IR and Matsuda index were significantly associated with the severity of sleep-related intermittent hypoxemia as assessed by the ODI (P for trend = 0.03 and 0.007, respectively). CONCLUSION Among middle-aged and older Japanese adults, sleep-related intermittent hypoxemia is associated with glucose intolerance and insulin resistance, and may contribute to the development of type 2 diabetes mellitus.

Heart Rate Variability, Insulin Resistance, and Insulin Sensitivity in Japanese Adults: The Toon Health Study

Background Although impaired cardiac autonomic function is associated with an increased risk of type 2 diabetes in Caucasians, evidence in Asian populations with a lower body mass index is limited. Methods Between 2009–2012, the Toon Health Study recruited 1899 individuals aged 30–79 years who were not taking medication for diabetes. A 75-g oral glucose tolerance test was used to diagnose type 2 diabetes, and fasting and 2-h-postload glucose and insulin concentrations were measured. We assessed the homeostasis model assessment index for insulin resistance (HOMA-IR) and Gutt’s insulin sensitivity index (ISI). Pulse was recorded for 5 min, and time-domain heart rate variability (HRV) indices were calculated: the standard deviation of normal-to-normal intervals (SDNN) and the root mean square of successive difference (RMSSD). Power spectral analysis provided frequency domain measures of HRV: high frequency (HF) power, low frequency (LF) power, and the LF:HF ratio. Results Multivariate-adjusted logistic regression models showed decreased SDNN, RMSSD, and HF, and increased LF:HF ratio were associated significantly with increased HOMA-IR and decreased ISI. When stratified by overweight status, the association of RMSSD, HF, and LF:HF ratio with decreased ISI was also apparent in non-overweight individuals. The interaction between LF:HF ratio and decreased ISI in overweight individuals was significant, with the odds ratio for decreased ISI in the highest quartile of LF:HF ratio in non-overweight individuals being 2.09 (95% confidence interval, 1.41–3.10). Conclusions Reduced HRV was associated with insulin resistance and lower insulin sensitivity. Decreased ISI was linked with parasympathetic dysfunction, primarily in non-overweight individuals.

The Association between Concentrations of Green Tea and Blood Glucose Levels

Our objective was to examine whether habitual green tea consumption is associated with blood glucose levels and other biomarkers of glucose metabolism. We conducted a cross-sectional study of 35 male volunteers, 23–63 years old and residing in Shizuoka Prefecture in Japan. Biochemical data were measured and we conducted a questionnaire survey on health, lifestyle, and nutrition, as well as frequency of consumption and concentrations (1%, 2%, and 3%) of green tea. Men who consumed a 3% concentration of green tea showed lower mean values of fasting blood glucose and fructosamine than those who consumed a 1% concentration. Fasting blood glucose levels were found to be significantly associated with green tea concentration (β = −0.14, p = 0.03). However, green tea consumption frequency showed no significant differences in mean levels of blood glucose, fructosamine and hemoglobin A1c. In conclusion, our findings suggest that the consumption of green tea at a high concentration has the potential to reduce blood glucose levels.

C-Reactive Protein and Cardiovascular Disease in East Asians: A Systematic Review

Elevated C-reactive protein (CRP) levels are associated with an increased risk of cardiovascular disease (CVD) in Caucasians; however, evidence is lacking for East Asians, who have low CRP levels. PubMed and Google Scholar searches were conducted (1966 through September 2014), and eight prospective studies in East Asian countries (China, Hong Kong, Japan, Korea, Macao, Mongolia, and Taiwan) that documented risk ratios of elevated CRP for CVD were included for meta-analysis with random-effects models. The overall association between CRP levels and stroke was significant in six studies (risk ratio = 1.40 [95% confidence interval {CI}, 1.10-1.77], P = 0.008). The association with ischemic stroke was more evident in subgroup analyses. For coronary heart disease (CHD) and CVD, the risk ratio was 1.75 (95% CI, 0.96-3.19, P = 0.07) and 1.76 (95% CI, 1.29-2.40, P < 0.001), respectively. Although East Asians have low CRP levels, this meta-analysis shows that elevated CRP levels were significantly associated with an increased risk of stroke, primarily ischemic stroke.

Cellular growth factors in relation to mortality from cardiovascular disease in middle-aged Japanese: The JACC study

OBJECTIVE Limited evidence has been available on the relationships of cellular growth factors with cardiovascular disease in population-based samples. METHODS We conducted a nested case-control study under a large prospective cohort study (JACC study) where a total of 39,242 subjects aged 40-79 years provided serum sample. We measured cellular growth factors [insulin-like growth factors I, II and binding protein-3 (IGF-I, IGF-II and IGFBP-3) and transforming growth factor (TGF-β1)] among cases and controls, matched for sex, age, area of residence and year of serum storage. RESULTS AND CONCLUSIONS During the follow-up for 9 years, there were 233 deaths from total stroke (49 subarachnoid hemorrhages, 55 intraparenchymal hemorrhages, 71 ischemic strokes), and 97 deaths from coronary heart disease. The multivariable odds ratio (95%CI) of intraparenchymal hemorrhage associated with a 1-SD increment of IGF-I (men:4 8 ng/ml, women: 61 ng/ml) was 0.31 (0.14-0.71). That of ischemic stroke associated with a 1-SD increment of TGF-β1 (men: 8.0 ng/ml, women: 10.9 ng/ml) was 0.58 (0.34-0.98). Serum IGF-II and IGFBP-3 were not associated with mortality from any outcomes. In conclusion, IGF-I was inversely associated with mortality from intraparenchymal hemorrhage while TGF-β1 was so with ischemic stroke, suggesting potential roles of cellular proliferation in the development or prognosis of stroke.

The reasonable reliability of a self-administered food frequency questionnaire for an urban, Japanese, middle-aged population: the Suita study ☆,☆☆

Because few studies have developed food frequency questionnaires (FFQ) and examined their reliability for Japanese urban populations, FFQ developed for urban Japanese populations may show reasonable reliability for estimating intakes of nutrients and food groups. Therefore, the objective of this study was to examine the reliability of an FFQ developed for a prospective cohort study in a Japanese urban area. A total of 29 men and 29 women aged 47 to 78 years were selected from participants in the Suita study from February 1997 to February 1998. Seven-consecutive-day dietary records (DR) was collected in each season (28-day DR). The FFQ were administered 3 times in total in each season, except in autumn. We calculated Spearman correlation coefficients to assess the validation of the first and third FFQ compared with 28-day DR and to assess the repeatability for 3-, 6-, and 9-month intervals. Reasonable validity of each FFQ compared with 28-day DR were observed for energy intake and for 27 nutrients, and 11 food groups were selected. Median (range) Spearman rank correlation coefficients for energy-adjusted nutrient and food group intakes of the first FFQ were 0.52 (0.14-0.88) and 0.53 (0.24-0.74), and those of the third FFQ were 0.51 (0.07-0.84) and 0.57 (0.16-0.75), respectively. The repeatability of each interval was relatively good; median (range) Spearman correlation coefficients of nutrients for 3-, 6-, and 9-month intervals were 0.67 (0.40-0.85), 0.63 (0.25-0.93), and 0.62 (0.31-0.87), respectively; those for food groups were 0.58 (0.42-0.76), 0.56 (0.24-0.80), and 0.65 (0.30-0.76), respectively. In conclusion, this FFQ is useful for evaluating the associations of nutrient and food intakes with cardiovascular diseases and their risk factors in Japanese urban populations.

Nocturia and prevalence of erectile dysfunction in Japanese patients with type 2 diabetes mellitus: The Dogo Study

Several epidemiological studies have reported a positive association between nocturia and erectile dysfunction (ED). Yet only limited evidence exists regarding the association between nocturia and ED among patients with type 2 diabetes mellitus, although nocturia and ED are common among type 2 diabetes mellitus patients.

Associations of serum β-carotene and retinol concentrations with insulin resistance: The Toon Health Study

OBJECTIVE Although green and yellow vegetables have beneficial effects against type 2 diabetes, the relationship of their nutritive content with insulin resistance is poorly understood. The aim of this study was to examine the associations of serum β-carotene and retinol concentrations with glucose and insulin concentrations. METHODS We recruited 951 Japanese men and women ages 30 to 79 y who were not undergoing treatment for diabetes and measured their serum β-carotene and retinol concentrations. A 75-g oral glucose tolerance test was performed and the homeostasis model assessment for insulin resistance (HOMA-IR) and the Matsuda Index were calculated as measures of insulin resistance. Several confounding factors were adjusted for with multivariable logistic models. RESULTS Multivariable-adjusted odds ratios of the highest quartile of serum β-carotene compared with the lowest quartile for HOMA-IR >1.6 and Matsuda Index <4.9 were 0.56 (95% confidence interval, 0.34-0.94) and 0.62 (0.37-1.02), respectively. When stratified by sex and overweight status, these associations were observed for women and non-overweight individuals. Serum retinol concentration was not associated with either index. Furthermore, according to the nutritional survey, serum β-carotene concentration was associated with green and yellow vegetable intake (P = 0.01). CONCLUSION Our findings suggest that higher serum β-carotene levels, associated with higher intake of green and yellow vegetables, confer beneficial effects against insulin resistance.