Satoru Kodama

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.

Diabetes and Risk of Hearing Impairment in Adults: A Meta-Analysis

CONTEXTnRecently, several studies have investigated the relationship between diabetes and hearing impairment, but results were inconsistent.nnnOBJECTIVEnOur objective was to compare the prevalence of hearing impairment between diabetic and nondiabetic adults.nnnDATA SOURCESnWe performed a systematic literature search using MEDLINE (1950 to May 30, 2011) and EMBASE (1974 to May 30, 2011).nnnSTUDY SELECTIONnCross-sectional studies were included if data on numbers of hearing-impaired and non-hearing-impaired cases with diabetes were presented. Hearing impairment was limited to that assessed by pure-tone audiometry that included at least 2 kHz of frequency range and was defined as progressive, chronic, sensorineural, or without specified cause.nnnDATA EXTRACTIONnTwo authors independently extracted relevant data. Odd ratios (ORs) of hearing impairment related to diabetes calculated in each study were pooled with the random-effects model.nnnDATA SYNTHESISnData were obtained from 13 eligible studies (20,194 participants and 7,377 cases). Overall pooled OR (95% confidence interval) of hearing impairment for diabetic participants compared with nondiabetic participants was 2.15 (1.72-2.68). OR was higher in younger participants (mean age, ≤60 yr) than in those over 60 yr among which the OR remained significant (2.61 and 1.58, P = 0.008). The strength of the association between diabetes and prevalence of hearing impairment was not significantly influenced by whether participants were matched for age and gender (P = 0.68) or whether participants chronically exposed to noisy environments were excluded (P = 0.19).nnnCONCLUSIONSnCurrent meta-analysis suggests that the higher prevalence of hearing impairment in diabetic patients compared with nondiabetic patients was consistent regardless of age.

Quantitative relationship between body weight gain in adulthood and incident type 2 diabetes: a meta-analysis.

This meta‐analysis quantified the risk of type 2 diabetes mellitus (T2DM) preceded by body weight (BW) gain in the general population. Systematic literature searches retrieved 15 eligible studies. The BW gain was divided into early weight‐gain, which was defined as BW gain from early adulthood (18–24 years of age) to cohort entry (≥25 years of age), and late weight‐gain, which was defined as BW gain from cohort entry. The pooled relative risk (RR; 95% confidence interval [CI]) of T2DM for an increment of BW gain standardized into a 5‐kg m−2 increment in the body mass index (BMI) was 3.07 (2.49–2.79) for early weight‐gain and 2.12 (1.74–2.58) for late weight‐gain. When limiting analysis to studies that concurrently examined T2DM risk for current BMI (defined in both groups as BMI at cohort entry), a larger magnitude of T2DM risk was revealed for early weight‐gain compared with current BMI (RR [95% CI], 3.38 [2.20–5.18] vs. 2.39 [1.58–3.62]), while there was little difference between late weight‐gain (RR [95% CI], 2.21 [1.91–2.56]) and current BMI (RR [95% CI], 2.47 [1.97–3.30]). The meta‐analysis suggested that BW gain was a quantifiable predictor of T2DM, as well as current obesity in adults. Particularly, BW gain in early rather than middle‐to‐late adulthood played an important role in developing T2DM.

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)

OBJECTIVEnWe 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.nnnDESIGN, SETTING, AND PARTICIPANTSnStudied 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).nnnRESULTSnThe 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].nnnCONCLUSIONSnAlmost 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.

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.

Development of a new scoring system for predicting the 5 year incidence of type 2 diabetes in Japan: the Toranomon Hospital Health Management Center Study 6 (TOPICS 6).

Aims/hypothesisThe aims of this study were to assess the clinical significance of introducing HbA1c into a risk score for diabetes and to develop a scoring system to predict the 5xa0year incidence of diabetes in Japanese individuals.MethodsThe study included 7,654 non-diabetic individuals aged 40–75xa0years. Incident diabetes was defined as fasting plasma glucose (FPG) ≥7.0xa0mmol/l, HbA1c ≥6.5% (48xa0mmol/mol) or self-reported clinician-diagnosed diabetes. We constructed a risk score using non-laboratory assessments (NLA) and evaluated improvements in risk prediction by adding elevated FPG, elevated HbA1c or both to NLA.ResultsThe discriminative ability of the NLA score (age, sex, family history of diabetes, current smoking and BMI) was 0.708. The difference in discrimination between the NLA + FPG and NLA + HbA1c scores was non-significant (0.836 vs 0.837; pu2009=u20090.898). A risk score including family history of diabetes, smoking, obesity and both FPG and HbA1c had the highest discrimination (0.887, 95% CI 0.871, 0.903). At an optimal cut-off point, sensitivity and specificity were high at 83.7% and 79.0%, respectively. After initial screening using NLA scores, subsequent information on either FPG or HbA1c resulted in a net reclassification improvement of 42.7% or 52.3%, respectively (pu2009<u20090.0001). When both were available, net reclassification improvement and integrated discrimination improvement were further improved at 56.7% (95% CI 47.3%, 66.1%) and 10.9% (9.7%, 12.1%), respectively.Conclusions/interpretationInformation on HbA1c or FPG levels after initial screening by NLA can precisely refine diabetes risk reclassification.

Low Lung Function and Risk of Type 2 Diabetes in Japanese Men: The Toranomon Hospital Health Management Center Study 9 (TOPICS 9)

OBJECTIVEnTo evaluate the effect of elevated fasting plasma glucose (FPG) and hemoglobin A(1c) (HbA(1c)) concentrations on lung dysfunction and to prospectively investigate whether reduced lung function would be independently predictive of diabetes.nnnPARTICIPANTS AND METHODSnFrom January 6, 1997, through December 22, 2008, we observed 5346 men with no history of diabetes or lung dysfunction. Hazard ratios (HRs) for incident diabetes (FPG ≥126 mg/dL, HbA(1c) ≥6.5%, or self-reported clinician-diagnosed diabetes) were estimated for spirometry indices as continuous and categorical variables.nnnRESULTSnElevated HbA(1c) concentrations within the normal range were significantly and more strongly associated with reduced forced vital capacity and forced expiratory volume in the first second after expiration (FEV(1)) than were FPG concentrations. During a 4.0-year follow-up, diabetes developed in 214 individuals. A 10-point decrease in percentage of FEV(1) predicted value was associated with an increased HR of 1.21 (95% confidence interval [CI], 1.09-1.34; P=.001) for diabetes after adjustment for demographic factors and body mass index. This association remained significant even after adjustment for metabolic factors, smoking status, and FPG or HbA(1c) concentrations but was attenuated substantially after adjustment for baseline HbA(1c) values (HR, 1.13; 95% CI, 1.01-1.26; P=.03). Lower quartile (Q) categories of percentage of FEV(1) predicted value were associated with increased risk of diabetes independently of known predictors including HbA(1c) (HR, 1.73; 95% CI, 1.14-2.62 for Q1; and HR, 1.76; 95% CI, 1.15-2.69 for Q2).nnnCONCLUSIONnReduced lung function was significantly related to chronic glycemic exposure within a normal range. Relatively low pulmonary function was an independent risk factor for diabetes in apparently healthy Japanese men.

Stability and changes in metabolically healthy overweight or obesity and risk of future diabetes: Niigata wellness study

Stability and changes in obesity and metabolic health status from a baseline period and longitudinally investigated their impact on predicting future diabetes were assessed.

Risk of the development of Type 2 diabetes in relation to overall obesity, abdominal obesity and the clustering of metabolic abnormalities in Japanese individuals: does metabolically healthy overweight really exist? The Niigata Wellness Study

We investigated the risk of developing diabetes across various metabolic phenotypes by considering the presence of overall adiposity or abdominal adiposity and the number of metabolic abnormalities and aimed to clarify whether a ‘healthy overweight’ phenotype, that is, overweight with no metabolic abnormalities, was protective of the development of diabetes.

Use of high-normal levels of haemoglobin A1C and fasting plasma glucose for diabetes screening and for prediction: a meta-analysis

Using high‐normal levels of haemoglobin A1C (Abnormal‐A1C) or fasting plasma glucose (FPG) (Abnormal‐FPG) for diabetes screening are expected to improve the ability to detect persons with or at high risk of diabetes. We assessed the diagnostic and predictive capacity for diabetes of Abnormal‐A1C and Abnormal‐FPG. We compared these to the combined use of the two measures to the single use of either measurement.