Yoriko Heianza

Alcohol consumption and risk of atrial fibrillation: a meta-analysis.

OBJECTIVES The purpose of this meta-analysis is to summarize the estimated risk of atrial fibrillation (AF) related to alcohol consumption. BACKGROUND Results from observational studies examining the relationship between alcohol consumption and AF are inconsistent. METHODS A systematic electronic search of Medline (January 1966 to December 2009) and Embase (January 1974 to December 2009) databases was conducted for studies using key words related to alcohol and AF. Studies were included if data on effect measures for AF associated with habitual alcohol intake were reported or could be calculated. The effect measures for AF for the highest versus lowest alcohol intake in individual studies were pooled with a variance-based method. Linear and spline regression analyses were conducted to quantify the relationship between alcohol intake and AF risk. RESULTS Fourteen eligible studies were included in this meta-analysis. The pooled estimate of AF for the highest versus the lowest alcohol intake was 1.51 (95% confidence interval: 1.31 to 1.74). A linear regression model showed that the pooled estimate for an increment of 10 g per day alcohol intake was 1.08 (95% confidence interval: 1.05 to 1.10; R(2) = 0.43, p < 0.001). A spline regression model also indicated that the AF risk increased with increasing levels of alcohol consumption. CONCLUSIONS Results of this meta-analysis suggest that not consuming alcohol is most favorable in terms of AF risk reduction.

HbA1c 5·7–6·4% and impaired fasting plasma glucose for diagnosis of prediabetes and risk of progression to diabetes in Japan (TOPICS 3): a longitudinal cohort study

BACKGROUND The clinical relevance of the diagnostic criteria for prediabetes to prediction of progression to diabetes has been little studied. We aimed to compare the prevalence of prediabetes when assessed by the new glycated haemoglobin A(1c) (HbA(1c)) 5·7-6·4% criterion or by impaired fasting glucose, and assessed differences in progression rate to diabetes between these two criteria for prediabetes in a Japanese population. METHODS Our longitudinal cohort study included 4670 men and 1571 women aged 24-82 years without diabetes at baseline (diabetes was defined as fasting plasma glucose ≥7·0 mmol/L, self-reported clinician-diagnosed diabetes, or HbA(1c) ≥6·5%) who attended Toranomon Hospital (Tokyo, Japan) for a routine health check between 1997 and 2003. Participants with a baseline diagnosis of prediabetes according to impaired fasting glucose (fasting plasma glucose 5·6-6·9 mmol/L) or HbA(1c) 5·7-6·4%, or both, were divided into four groups on the basis of baseline diagnosis of prediabetes. Rate of progression to diabetes was assessed annually. FINDINGS Mean follow-up was 4·7 (SD 0·7) years. 412 (7%) of 6241 participants were diagnosed with prediabetes on the basis of the HbA(1c) 5·7-6·4% criterion. Screening by HbA(1c) alone missed 1270 (61%) of the 2092 prediabetic individuals diagnosed by a combination of impaired fasting glucose and HbA(1c) 5·7-6·4%. Overall cumulative probability of progression to diabetes did not differ significantly between participants with prediabetes discordantly diagnosed by either HbA(1c) or impaired fasting glucose alone (incidence was 7% for HbA(1c) alone [n=412 individuals and 30 incident cases] and 9% for impaired fasting glucose alone [n=1270, 108 cases]; log-rank test, p=0·3317). Multivariate-adjusted hazard ratios for incident diabetes were 6·16 (95% CI 4·33-8·77) for those diagnosed with prediabetes by impaired fasting glucose alone and 6·00 (3·76-9·56) for diagnosis by HbA(1c) alone, and were substantially increased to 31·9 (22·6-45·0) for diagnosis by both impaired fasting glucose and HbA(1c) compared with normoglycaemic individuals. INTERPRETATION Diagnosis of prediabetes by both the new HbA(1c) criterion and impaired fasting glucose identified individuals with an increased risk of progression to diabetes. Although the new HbA(1c) criterion identified fewer individuals at high risk than did impaired fasting glucose, the predictive value for progression to diabetes assessed by HbA(1c) 5·7-6·4% was similar to that assessed by impaired fasting glucose alone. The two tests used together could efficiently target people who are most likely to develop diabetes and allow for early intervention. FUNDING Japan Society for the Promotion of Science; Ministry of Health Labor and Welfare, Japan.

Comparisons of the Strength of Associations With Future Type 2 Diabetes Risk Among Anthropometric Obesity Indicators, Including Waist-to-Height Ratio: A Meta-Analysis

The aim of this meta-analysis was to compare the association of waist-to-height ratio (WHtR) with risk of incident diabetes with the associations of 3 other conventional obesity indicators (body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR)) with risk of incident diabetes. Literature searches in MEDLINE (January 1950 to April 27, 2011) and EMBASE (January 1974 to April 27, 2011) were conducted for prospective studies that made it possible to estimate the relative risk of diabetes per 1-standard deviation increase in WHtR, in addition to the RR of BMI, WC, or WHR. Strength of the estimated pooled relative risk for a 1-standard deviation increase of each indicator (expressed as RR(WHtR), RR(BMI), RR(WC), and RR(WHR)) was compared with a bivariate random-effects model. Pooled relative risks of the 15 eligible studies with 6,472 diabetes cases were 1.62 (95% CI: 1.48, 1.78) for RR(WHtR), 1.55 (95% CI: 1.43, 1.69) for RR(BMI), 1.63 (95% CI: 1.49, 1.79) for RR(WC), and 1.52 (95% CI: 1.40, 1.66) for RR(WHR). WHtR had an association stronger than that of BMI (P<0.001) or WHR (P<0.001). The present meta-analysis showed that WHtR has a modestly but statistically greater importance than BMI and WHR in prediction of diabetes. Nevertheless, measuring height in addition to WC appeared to have no additional benefit.

Association between physical activity and risk of all-cause mortality and cardiovascular disease in patients with diabetes: a meta-analysis.

OBJECTIVE The association between habitual physical activity (PA) and lowered risk of all-cause mortality (ACM) and cardiovascular disease (CVD) has been suggested in patients with diabetes. This meta-analysis summarizes the risk reduction in relation to PA, focusing on clarifying dose-response associations. RESEARCH DESIGN AND METHODS Electronic literature searches were conducted for cohort studies that examined relative risk (RR) of ACM or CVD in relation to PA in patients with diabetes. For the qualitative assessment, RR for the highest versus the lowest PA category in each study was pooled with a random-effects model. We added linear and spline regression analyses to assess the quantitative relationship between increases in PA and ACM and CVD risk. RESULTS There were 17 eligible studies. Qualitatively, the highest PA category had a lower RR [95% CI] for ACM (0.61 [0.52–0.70]) and CVD (0.71 [0.60–0.84]) than the lowest PA category. The linear regression model indicated a high goodness of fit for the risk of ACM (adjusted R2 = 0.44, P = 0.001) and CVD (adjusted R2 = 0.51, P = 0.001), with the result that a 1 MET-h/day incrementally higher PA was associated with 9.5% (5.0–13.8%) and 7.9% (4.3–11.4%) reductions in ACM and CVD risk, respectively. The spline regression model was not significantly different from the linear model in goodness of fit (P = 0.14 for ACM risk; P = 0.60 for CVD risk). CONCLUSIONS More PA was associated with a larger reduction in future ACM and CVD risk in patients with diabetes. Nevertheless, any amount of habitual PA was better than inactivity.

Skipping breakfast and prevalence of overweight and obesity in Asian and Pacific regions: a meta-analysis.

OBJECTIVE In Western countries, skipping breakfast is associated with a high prevalence of overweight and obesity. This meta-analysis aimed to determine if the same relationship exists in Asian and Pacific regions. METHODS A systematic literature search was performed for observational studies using a cross-sectional design that examined the relationship between frequency of eating breakfast and overweight or obesity. Odds ratios (ORs) for overweight or obesity were pooled with a variance-based method. RESULTS Nineteen studies (93,108 total participants and 19,270 overweight or obese cases) were included. The pooled OR [95% confidence intervals (CI)] of overweight or obesity for the lowest vs. highest category of breakfast frequency was 1.75 [1.57 to 1.95] (P<0.001). Between-study heterogeneity in the associations strength was highly significant (I-squared=36.4%, P<0.001), although a positive OR was shown in all but one included study. However, no study characteristics could be identified to explain the heterogeneity. CONCLUSION This meta-analysis suggests that a positive association between skipping breakfast and overweight and obesity is globally observed regardless of cultural diversity among countries. Promoting the eating of breakfast in all populations may be beneficial.

Metabolically Healthy Obesity, Presence or Absence of Fatty Liver, and Risk of Type 2 Diabetes in Japanese Individuals: Toranomon Hospital Health Management Center Study 20 (TOPICS 20)

OBJECTIVE We investigated whether the metabolically healthy obese (MHO) phenotype was associated with an increased risk of the development of diabetes. If so, we aimed to determine what factors could explain this finding. DESIGN, SETTING, AND PARTICIPANTS Studied were 8090 Japanese individuals without diabetes. Metabolic health status was assessed by common clinical markers: blood pressure, triglycerides, high-density lipoprotein-cholesterol, and fasting glucose concentrations. The cutoff value for obesity or normal weight (NW) was a body mass index of 25.0 kg/m(2). RESULTS The 5-year incidence rate of diabetes was 1.2% (n = 58 of 4749) in metabolically healthy NW (MHNW) individuals, 2.8% (n = 20 of 719) in MHO individuals, 6.0% (n = 102 of 1709) in metabolically abnormal NW individuals, and 10.3% (n = 94 of 913) in metabolically abnormal obese individuals. Although MHO individuals had no or one metabolic factor, 47.8% had ultrasonographic fatty liver (FL). The MHO group had a significantly increased risk of diabetes compared with the MHNW group [multivariate adjusted odds ratio (OR) 2.23 (95% confidence interval [CI] 1.33, 3.75)], but this risk was attenuated after adjustment for FL. Compared with the MHNW/non-FL group, the risk of diabetes in the MHO/non-FL group was not significantly elevated [OR 1.01 (95% CI 0.35, 2.88)]. However, the MHO/FL and MHNW/FL groups had similarly elevated risks of diabetes [OR 4.09 (95% CI 2.20, 7.60) and 3.16 (1.78, 5.62), respectively]. CONCLUSIONS Almost half of the MHO participants had FL, which partially explained the increased risk of diabetes among the obese phenotypes. The presence of FL should be evaluated to assess whether an individual was actually in a metabolically benign state for the prediction of diabetes.

Gut Microbiota Metabolites and Risk of Major Adverse Cardiovascular Disease Events and Death: A Systematic Review and Meta‐Analysis of Prospective Studies

Background Gut microbial metabolites have been implicated as novel risk factors for cardiovascular events and premature death. The strength and consistency of associations between blood concentrations of the gut microbial metabolites, trimethylamine‐N‐oxide (TMAO) and its precursors, with major adverse cardiovascular events (MACE) or death have not been comprehensively assessed. We quantified associations of blood concentrations of TMAO and its precursors with risks of MACE and mortality. Methods and Results PubMed and Embase databases were searched up, and a total of 19 prospective studies from 16 publications (n=19 256, including 3315 incident cases) with quantitative estimates of the associations of TMAO with the development of MACE or death were included in our main analysis. Multivariate‐adjusted relative risks (RRs) were used when these were available. Elevated concentrations of TMAO were associated with a pooled RR of 1.62 (95% CI, 1.45, 1.80; P heterogeneity=0.2; I2=23.5%) for MACE compared with low TMAO levels, and 1 study of black participants influenced the heterogeneity of the association. After excluding the data of blacks, the RRs were not different according to body mass index, prevalence of diabetes mellitus, history of cardiovascular diseases, and kidney dysfunction. Furthermore, elevated TMAO concentrations were associated with a pooled RR of 1.63 (1.36, 1.95) for all‐cause mortality. Individuals with elevated concentrations of TMAO precursors (l‐carnitine, choline, or betaine) had an approximately 1.3 to 1.4 times higher risk for MACE compared to those with low concentrations. Conclusions Elevated concentrations of TMAO and its precursors were associated with increased risks of MACE and all‐cause mortality independently of traditional risk factors.

Effect of Postmenopausal Status and Age at Menopause on Type 2 Diabetes and Prediabetes in Japanese Individuals: Toranomon Hospital Health Management Center Study 17 (TOPICS 17)

OBJECTIVE Findings on the effect of menopause or age at menopause on the presence of hyperglycemia are controversial, and why women after menopause have a higher probability of having hyperglycemia than men in the same age range remains unknown. RESEARCH DESIGN AND METHODS We reviewed data on 29,189 men, 6,308 premenopausal women, and 4,570 postmenopausal women in Japan. Odds ratios (ORs) for diabetes or prediabetes indicated by American Diabetes Association criteria were calculated for men and for pre- and postmenopausal women. RESULTS Compared with premenopausal women, women after natural menopause had an age-adjusted OR of 1.40 (95% CI 1.03–1.89) for diabetes, and women after menopause by surgical or other causes had an age-adjusted OR of 1.59 (1.07–2.37). The age-adjusted OR in men was 4.02 (3.15–5.14). Compared with premenopausal nondiabetic women, postmenopausal nondiabetic women had a significantly elevated OR of 1.33 (1.20–1.48) for prediabetes; nondiabetic men had an OR of 1.93 (1.77–2.10) independently of age and demographic and metabolic factors. Even among women aged <50 years, postmenopausal status was significantly associated with an elevated OR (1.50 [1.18–1.91]) for dysglycemia (either diabetes or prediabetes). Postmenopausal women aged ≥50 years had a particularly elevated OR for dysglycemia, regardless of age at menopause. CONCLUSIONS The postmenopausal state was significantly associated with the presence of dysglycemia independently of normal aging, although the increased probability in postmenopausal women did not equal that in men. Among women, menopause and older age might additively influence the elevated probability of dysglycemia.

Screening for pre‐diabetes to predict future diabetes using various cut‐off points for HbA1c and impaired fasting glucose: the Toranomon Hospital Health Management Center Study 4 (TOPICS 4)

Diabet. Med. 29, e279‐e285 (2012)

Role of alcohol drinking pattern in type 2 diabetes in Japanese men: the Toranomon Hospital Health Management Center Study 11 (TOPICS 11)

BACKGROUND Findings of past studies on the effect of drinking patterns on diabetes risk have been inconsistent. OBJECTIVE We aimed to investigate the role of drinking frequency and usual quantity consumed in the development of type 2 diabetes. DESIGN Enrolled were 1650 Japanese men without diabetes (diabetes: fasting plasma glucose ≥7.0 mmol/L, glycated hemoglobin ≥6.5%, or self-reported clinician-diagnosed diabetes). Average alcohol consumption and 12 combinations of frequency and usual quantity per drinking occasion were assessed at the baseline examination. The absolute risk and HR for the development of diabetes were calculated. RESULTS During a mean follow-up period of 10.2 y, 216 individuals developed diabetes. Lifetime abstainers (n = 153) had a relatively low incidence of diabetes (9.1/1000 person-years), similar to moderate consumers (99-160 g ethanol/wk; 9.0/1000 person-years). Increasingly higher quantities of alcohol usually consumed per occasion increased the risk of diabetes regardless of drinking frequency. The lowest incidence rate of diabetes (8.5/1000 person-years) was associated with the consumption of <1 drink (<23 g ethanol) per occasion over ≥6 times/wk. Binge drinking (≥3 drinks per occasion) significantly increased the risk of future diabetes regardless of frequency (HR: 1.79; 95% CI: 1.17, 2.74) compared with <1 drink per occasion. CONCLUSIONS Among current drinkers, a drinking pattern of <1 drink per occasion regularly over 6 times within a week was associated with the lowest risk of developing diabetes. Usual quantity per drinking occasion was a more important determinant than was weekly drinking frequency in the association between alcohol consumption and risk of diabetes in Japanese men.