Influence of an SGLT2 inhibitor, tofogliflozin, on the resting heart rate in relation to adipose tissue insulin resistance.

AIMS: To examine the effects of a sodium-glucose co-transporter 2 (SGLT2) inhibitor, tofogliflozin, on resting heart rate by exploring baseline factors that independently influenced changes in the resting heart rate. METHODS: Data on 419 participants in tofogliflozin phase 2/3 trials were analysed. Changes in resting heart rate from baseline to week 24 were analysed using an analysis of covariance (ANCOVA) model with groups (tofogliflozin/placebo) as a fixed effect and baseline values as covariates. The antilipolytic effect was evaluated as adipose tissue insulin resistance (Adipo-IR) and was calculated as the product of fasting insulin and free fatty acid. Multivariate analysis evaluated independent factors for changes in resting heart rate from baseline to week 24. RESULTS: Of the participants, 58% were men, and mean age, HbA1c , BMI and resting heart rate were 57.6 years, 65 mmol/mol (8.1%), 25.5 kg/m2 and 66 bpm, respectively. At week 24, adjusted mean difference vs. placebo in the change from baseline was -2.3 bpm [95% confidence interval (CI) -4.6, -0.1] with tofogliflozin. Changes in resting heart rate were positively correlated with changes in Adipo-IR, whereas reductions in HbA1c , body weight and blood pressure were similar independent of changes in resting heart among quartiles of resting heart rate change. On multivariate analysis, higher baseline resting heart rates and Adipo-IR values were significantly associated with greater reductions in resting heart rate. CONCLUSIONS: Tofogliflozin corrected resting heart rate levels in accordance with baseline levels. Correction of high resting heart rates may be attributed to improved adipose tissue insulin resistance, leading to correction of hyperinsulinaemia.

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.

AIMS: 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. METHODS: We studied 29 564 Japanese individuals without diabetes. The 5-year incidence of diabetes was assessed according to a combination of either overweight (BMI ≥ 25.0 kg/m(2) ) or abdominal obesity (waist circumference ≥ 90 cm in men and ≥ 80 cm in women) and the number of metabolic factors present (hypertension, elevated triglyceride concentration, low HDL cholesterol concentration and impaired fasting glucose). RESULTS: A total of 1188 individuals developed diabetes. Compared with normal weight individuals with none of the four metabolic abnormalities, in overweight individuals with none of the four abnormalities there was an odds ratio (OR) of 2.32 [95% confidence interval (CI) 1.50, 3.59] for diabetes; having any one metabolic abnormality increased the risk of developing diabetes among normal weight individuals [OR 3.23 (2.55, 4.10)] and overweight individuals [OR 5.00 (3.77, 6.63)]. Among overweight individuals, the presence of impaired fasting glucose alone substantially elevated the risk of diabetes by 8.98-fold (5.52, 14.6) in comparison with the absence of the four metabolic factors. CONCLUSIONS: Being 'healthy overweight' was associated with a higher OR of developing future diabetes among Japanese individuals than normal weight individuals with no metabolic abnormalities, and being overweight with one or more abnormalities had a further elevated OR compared with 'healthy overweight' people.

Fatal tracheal aspergillosis during rituximab combined chemotherapy for diffuse large B-cell lymphoma that developed after lung transplantation.

Invasive tracheal aspergillosis (ITA) is an infection that is unique to patients who have undergone lung transplantation (LT). Although the activity of this disease often appears on imaging, we encountered a case of ITA that became exacerbated, despite few computed tomography (CT) findings, during rituximab combined chemotherapy for diffuse large B-cell lymphoma. ITA developed during immunosuppressive therapy after LT. Because CT findings may show false-negative results, bronchoscopy is recommended for such cases.

Role of sleep duration as a risk factor for Type 2 diabetes among adults of different ages in Japan: the Niigata Wellness Study.

AIM: To compare the role of short sleep duration as a risk factor for diabetes among adults of different ages. METHODS: The study enrolled 38987 Japanese individuals without diabetes, and the 8-year risk of developing diabetes attributable to different sleep durations (< 5.5 h, 5.5 to < 6.5 h, 6.5 to < 7.0 h, 7.0-7.5 h, > 7.5-8.0 h, or > 8.0 h) was assessed among individuals aged ≤ 45, 46-59 or ≥ 60 years. RESULTS: During the 8-year follow-up period, 2085 individuals developed diabetes. Overall, individuals with a short sleep duration of < 5.5 h or 5.5 to < 6.5 h had, respectively, a 1.53-fold (95% CI 1.19, 1.97) or 1.25-fold (95% CI 1.10, 1.42) increased risk of diabetes as compared with those who had 7.0-7.5 h of sleep. A sleep duration of < 5.5 h or 5.5 to < 6.5 h was predictive of the development of diabetes among individuals aged ≤ 45 years, but not among those aged ≥ 60 years. With increasing age, the effect of short sleep duration on the risk of diabetes was attenuated. CONCLUSIONS: Short sleep duration was predictive of diabetes among young or middle-aged Japanese adults but not among elderly individuals after age was considered. Managing habitual short sleep and the possible reasons for having such short sleep duration could be particularly important for young or middle-aged adults in the development of future diabetes.

Comparison of different aspects of BMI history to identify undiagnosed diabetes in Japanese men and women: Toranomon Hospital Health Management Center Study 12 (TOPICS 12).

AIMS: To examine current BMI and various aspects of BMI history as pre-screening tools for undiagnosed diabetes in Japanese individuals. METHODS: This cross-sectional study included 16 226 men and 7026 women aged 30-75 years without a self-reported history of clinician-diagnosed diabetes. We estimated the probability of having undiagnosed diabetes (fasting glucose ≥ 7.0 mmol/l and/or HbA1c ≥ 48 mmol/mol (≥ 6.5%) for the following variables: current BMI, BMI in the early 20s (BMI(20y)), lifetime maximum BMI (BMI(max)), change between BMI in the early 20s and current BMI (ΔBMI(20y-cur)), change between BMI in the early 20s and maximum BMI (ΔBMI(20y-max)), and change between lifetime maximum and current BMI (ΔBMI(max-cur)). RESULTS: The prevalence of undiagnosed diabetes was 3.3% (771/23252) among participants. BMI(max) , ΔBMI(20y-max) and current BMI (1-sd increments) were more strongly associated with diabetes than the other factors (multivariate odds ratio 1.58 [95% CI 1.47-1.70] in men and 1.65 [95% CI 1.43-1.90] in women for BMI(max) ; multivariate odds ratio 1.47 [95% CI 1.37-1.58] in men and 1.61 [95% CI 1.41-1.84] in women for ΔBMI(20y-max) ; multivariate odds ratio 1.47 [95% CI 1.36-1.58] in men and 1.63 [95% CI 1.40-1.89] in women for current BMI). The probability of having diabetes was markedly higher in those with both the highest tertile of BMI(max) and greatest ΔBMI(20y-max) ; however, a substantially lower likelihood of diabetes was observed among individuals with the lowest and middle tertiles of current BMI (< 24.62 kg/m² in men and < 22.54 kg/m² in women). CONCLUSIONS: Lifetime maximum BMI and BMI changes from early adulthood were strongly associated with undiagnosed diabetes. Adding BMI history to people's current BMI would improve the identification of individuals with a markedly higher probability of having undiagnosed diabetes.

Ghrelin signalling in ß-cells regulates insulin secretion and blood glucose.

Insulin secretion from pancreatic islet ß-cells is stimulated by glucose. Glucose-induced insulin release is potentiated or suppressed by hormones and neural substances. Ghrelin, an acylated 28-amino acid peptide, was isolated from the stomach in 1999 as the endogenous ligand for the growth hormone (GH) secretagogue-receptor (GHS-R). Circulating ghrelin is produced predominantly in the stomach and to a lesser extent in the intestine, pancreas and brain. Ghrelin, initially identified as a potent stimulator of GH release and feeding, has been shown to suppress glucose-induced insulin release. This insulinostatic action is mediated by Gα(i2) subtype of GTP-binding proteins and delayed outward K⁺ (Kv) channels. Interestingly, ghrelin is produced in pancreatic islets. The ghrelin originating from islets restricts insulin release and thereby upwardly regulates the systemic glucose level. Furthermore, blockade or elimination of ghrelin enhances insulin release, which can ameliorate glucose intolerance in high-fat diet fed mice and ob/ob mice. This review focuses on the insulinostatic action of ghrelin, its signal transduction mechanisms in islet ß-cells, ghrelin's status as an islet hormone, physiological roles of ghrelin in regulating systemic insulin levels and glycaemia, and therapeutic potential of the ghrelin-GHS-R system as the target to treat type 2 diabetes.

Leisure-time physical activity is a significant predictor of stroke and total mortality in Japanese patients with type 2 diabetes: analysis from the Japan Diabetes Complications Study (JDCS).

AIMS/HYPOTHESIS: Our aim was to clarify the association between leisure-time physical activity (LTPA) and cardiovascular events and total mortality in a nationwide cohort of Japanese diabetic patients. METHODS: Eligible patients (1,702) with type 2 diabetes (mean age, 58.5 years; 47% women) from 59 institutes were followed for a median of 8.05 years. A comprehensive lifestyle survey including LTPA and occupation was performed using standardised questionnaires. Outcome was occurrence of coronary heart disease (CHD), stroke and total mortality. The adjusted HR and 95% CI were calculated by Cox regression analysis. RESULTS: A significant reduction in HR in patients in the top (≥ 15.4 metabolic equivalents [MET] h/week) vs the bottom tertile (≤ 3.7 MET h/week) of LTPA, adjusted by age, sex and diabetes duration, was observed in stroke (HR 0.55, 95% CI 0.32, 0.94) and total mortality (HR 0.49, 95% CI 0.26, 0.91) but not in CHD (HR 0.77, 95% CI 0.48, 1.25). The HR for stroke became borderline significant or nonsignificant after adjustment for lifestyle or clinical variables including diet or serum lipids. The significantly reduced total mortality by LTPA was independent of these variables and seemed not to be, at least mainly, attributed to reduced cardiovascular disease. CONCLUSIONS/INTERPRETATION: In Japanese persons with type 2 diabetes, LTPA of 15.4 MET h/week or more was associated with a significantly lower risk of stroke partly through ameliorating combinations of cardiovascular risk factors. It was also associated with significantly reduced total mortality but independently of cardiovascular risk factors or events. These findings, implying differences from Western diabetic populations, should be considered in the clinical management of East Asians with diabetes.

Low BMI at age 20 years predicts gestational diabetes independent of BMI in early pregnancy in Japan: Tanaka Women's Clinic Study.

AIMS: Maternal obesity and weight gain since early adulthood are known predictors of gestational diabetes in Western countries. However, their impact has not been evaluated well in Asia, where mean BMI levels are generally lower than in Western countries. We therefore examined the associations of BMI at age 20 years and BMI change since age 20 years with the risk of gestational diabetes in Japanese pregnant women. METHODS: Six hundred and twenty-four consecutive pregnant women without recognized diabetes before pregnancy, whose initial obstetric clinic visit was before 13 weeks' gestation, were prospectively observed. Weight at age 20 years was self-reported. Baseline height and weight measurements were obtained at the initial obstetric visit. Multivariate logistic regression analysis estimated the risk of incident gestational diabetes for BMI change since 20 years and BMI at age 20 years. RESULTS: Twenty-eight women developed incident gestational diabetes. By multivariate logistic regression analysis that adjusted for maternal age, parity and baseline BMI, we observed a statistically significant inverse association between BMI at age 20 years and incidence of gestational diabetes (odds ratio 0.68, 95% CI 0.51-0.92). Similarly, when we assessed the association of BMI change since age 20 years, adjusted for maternal age and parity, BMI change was associated with an increased risk of gestational diabetes (odds ratio 1.26, 95% CI 1.03-1.53). When we focused on the threshold of risk of gestational diabetes, women with BMI at 20 years of less than 18 kg/m(2) had a 6.30-fold (2.26-17.59) greater risk than women with both BMI at age 20 years of 18 kg/m(2) or more and BMI change since age 20 years of less than 1.85. CONCLUSIONS: Both low BMI at age 20 years and BMI change since age 20 years were significantly associated with increased risk of incident gestational diabetes.

Association of living alone with the presence of undiagnosed diabetes in Japanese men: the role of modifiable risk factors for diabetes: Toranomon Hospital Health Management Center Study 13 (TOPICS 13).

AIMS: To investigate whether living alone was associated with the presence of undiagnosed diabetes and whether this association could be attenuated by modifiable lifestyle habits. METHODS: This cross-sectional study included 6400 Japanese men without a history of diagnosed diabetes. Individuals with currently undiagnosed diabetes were identified through fasting glucose concentration ≥7.0 mmol/l or HbA1c concentration ≥ 48 mmol/mol (≥ 6.5%). Effect modification was examined using body mass index, hypertension, history of dyslipidaemia, drinking habits, smoking habits, physical activity, vegetable intake, emotional stress and depressed mood. RESULTS: Men who lived alone (n = 1098) had a significantly elevated odds ratio for having undiagnosed diabetes in an age-adjusted model (odds ratio 1.45, 95% CI 1.07, 1.96; P = 0.018). After adjustment for lifestyle factors, the association was slightly attenuated (odds ratio 1.40, 95% CI 1.02, 1.91; P = 0.036). After further adjustment for all factors mentioned above, living alone was still marginally significantly associated with the presence of undiagnosed diabetes (odds ratio 1.38, 95% CI 1.003, 1.90; P = 0.048). A significant association of living alone with the presence of undetected diabetes was particularly observed among men who were overweight, currently smoked and were physically inactive, or had any one of those three factors. CONCLUSIONS: The association between undiagnosed diabetes and living alone can be partially influenced by modifiable lifestyle factors. Men who lived alone, especially those who did not engage in favourable lifestyle habits, were more likely to have undiagnosed diabetes. Such individuals have a higher probability of having undetected diabetic hyperglycaemia and would need to undergo glucose tests to identify the disease.

Effect of Bifidobacterium bifidum BF-1 on gastric protection and mucin production in an acute gastric injury rat model.

Homeostasis in the stomach environment is maintained by the balance of protective factors such as gastric mucus and aggressive factors such as gastric acid, stress, alcohol, and drugs. An overload of aggressive factors that upsets this balance can induce gastric injury. Fermented milk that contains Bifidobacterium bifidum BF-1 (BF-1), a probiotic strain, and Streptococcus thermophilus YIT 2021 (ST) is known to improve Helicobacter pylori-associated gastritis in humans. Here, we investigated the gastroprotective potential of BF-1 in a rat model of acid-ethanol-induced acute gastric injury to fully elucidate its potential compared with ST. Living BF-1, ST, or vehicle was orally administrated to rats, and acid-ethanol gastric injury was induced 2h later. The gastric injury rate was determined and shown to be significantly lower in the BF-1 group than in the vehicle group, which showed a similar level to the ST group. The production of gastric mucin and the expression of several target genes associated with protection and inflammation were examined before and after induction of gastric injury. Interestingly, mucin 5ac (muc5ac) gene expression in gastric corpus samples and gastric mucin production in stomach samples from the BF-1 group, but not the ST group, were significantly higher than those in the respective samples from the vehicle group. These findings indicate that BF-1 has the potential to provide gastroprotection, alleviating acute gastric injury by enhancing the production of gastric mucin in a rat model.

HbA(1c) variability and the development of microalbuminuria in type 2 diabetes: Tsukuba Kawai Diabetes Registry 2.

AIMS/HYPOTHESIS: The aim of this study was to examine the association between HbA(1c) variability and the development of microalbuminuria as defined by an albumin/creatinine ratio ≥ 3.4 mg/mmol (≥ 30 mg/g) in at least two of three consecutive urine samples in Japanese patients with type 2 diabetes. METHODS: HbA(1c) level was measured in 812 serially registered normoalbuminuric adults aged 21-79 years with type 2 diabetes. After registration, a 1-year period to establish baseline values for mean HbA(1c) and HbA(1c) variability (measured as the intrapersonal SD of serially collected HbA(1c)) was decided upon. The association between HbA(1c) variability and the development of microalbuminuria was determined by Cox regression analysis after adjustment for other risk factors for microalbuminuria. RESULTS: Microalbuminuria occurred in 193 patients during the observation period of (mean ± SD) 4.3 ± 2.7 years. Even after adjustment for mean HbA(1c), HbA(1c) variability was a significant predictor of microalbuminuria independently of the mean HbA(1c); the HR for every 1% (95% CI) increase in mean HbA(1c) was 1.22 (1.06, 1.40) (p = 0.005), and that for HbA(1c) variability was 1.35 (1.05, 1.72) (p = 0.019). The effects of these two variables were quite similar when 1 SD was used; the HR for every 1 SD increase (95% CI) in HbA(1c) was 1.23 (1.07, 1.43) (p = 0.005), and that for HbA(1c) variability was 1.20 (1.03, 1.39) (p = 0.019). CONCLUSIONS/INTERPRETATION: HbA(1c) variability affects the development of microalbuminuria independently of mean HbA(1c) in type 2 diabetes. Further studies should be performed to evaluate the influence of HbA(1c) variability on other complications and in individuals of other ethnicities with type 2 diabetes.

Chronic kidney disease categories and renal-cardiovascular outcomes in type 2 diabetes without prevalent cardiovascular disease: a prospective cohort study (JDDM25).

AIMS/HYPOTHESIS: In type 2 diabetic patients at low risk for cardiovascular disease (CVD), the relationship between the clinical course of nephropathy by stage of chronic kidney disease (CKD) and onset of CVD remains unclear. Clarification of this relationship is important for clinical decision-making for both low- and high-risk diabetic patients. METHODS: This 4 year prospective study enrolled 2,954 type 2 diabetic patients with no prevalent CVD, and serum creatinine <176.8 µmol/l. The risk for CVD onset (non-fatal and fatal CVD and stroke, and peripheral arterial disease) was assessed according to CKD stage categorised by urinary albumin-to-creatinine ratio (ACR; mg/mmol) and estimated GFR (eGFR; ml min(-1) 1.73 m(-2)). Association of progression from 'no CKD' stage (ACR <3.5 mg/mmol and eGFR ≥ 90 ml min(-1) 1.73 m(-2)) with risk for CVD onset was also evaluated. RESULTS: During follow-up (median 3.8 years), 89 CVD events occurred. Compared with patients with 'no CKD' as reference, those with ACR ≥ 35.0 mg/mmol with co-existing eGFR 60-89 ml min(-1) 1.73 m(-2) or <60 ml min(-1) 1.73 m(-2) showed increased risk for CVD onset, whereas those with eGFR ≥ 90 ml min(-1) 1.73 m(-2) did not. Those with ACR <3.5 mg/mmol and eGFR <60 ml min(-1) 1.73 m(-2) did not show any increased risk. Among patients with 'no CKD' stage at baseline, those who progressed to ACR ≥ 3.5 mg/mmol during follow-up showed an increased risk compared with those who did not, whereas those who progressed to eGFR <90 ml min(-1) 1.73 m(-2) did not have increased risk. CONCLUSIONS/INTERPRETATION: The risk for CVD was associated with progression of albuminuria stage rather than eGFR stage in type 2 diabetic patients at relatively low risk for CVD.

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/HYPOTHESIS: The aims of this study were to assess the clinical significance of introducing HbA(1c) into a risk score for diabetes and to develop a scoring system to predict the 5 year incidence of diabetes in Japanese individuals. METHODS: The study included 7,654 non-diabetic individuals aged 40-75 years. Incident diabetes was defined as fasting plasma glucose (FPG) ≥7.0 mmol/l, HbA(1c) ≥6.5% (48 mmol/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 HbA(1c) or both to NLA. RESULTS: The 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 + HbA(1c) scores was non-significant (0.836 vs 0.837; p = 0.898). A risk score including family history of diabetes, smoking, obesity and both FPG and HbA(1c) 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 HbA(1c) resulted in a net reclassification improvement of 42.7% or 52.3%, respectively (p < 0.0001). 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/INTERPRETATION: Information on HbA(1c) or FPG levels after initial screening by NLA can precisely refine diabetes risk reclassification.

Effect of Web-based lifestyle modification on weight control: a meta-analysis.

OBJECTIVE: Web-based treatment programs are attractive in primary care because of their ability to reach numerous individuals at low cost. Our aim of this meta-analysis is to systematically review the weight loss or maintenance effect of the Internet component in obesity treatment programs. METHODS: MEDLINE and EMBASE literature searches were conducted to identify studies investigating the effect of Web-based individualized advice on lifestyle modification on weight loss. Randomized controlled trials that consisted of a Web-user experimental and non-Web user control group were included. Weight changes in the experimental group in comparison with the control group were pooled with a random-effects model. RESULTS: A total of 23 studies comprising 8697 participants were included. Overall, using the Internet had a modest but significant additional weight-loss effect compared with non-Web user control groups (-0.68 kg, P=0.03). In comparison with the control group, stratified analysis indicated that using the Internet as an adjunct to obesity care was effective (-1.00 kg, P<0.001), but that using it as a substitute for face-to-face support was unfavorable (+1.27 kg, P=0.01). An additional effect on weight control was observed when the aim of using the Internet was initial weight loss (-1.01 kg; P=0.03), but was not observed when the aim was weight maintenance (+0.68 kg; P=0.26). The relative effect was diminished with longer educational periods (P-trend=0.04) and was insignificant (-0.20 kg; P=0.75) in studies with educational periods of 12 months or more. CONCLUSION: The current meta-analysis indicates that the Internet component in obesity treatment programs has a modest effect on weight control. However, the effect was inconsistent, largely depending on the type of usage of the Internet or the period of its use.

Screening for pre-diabetes to predict future diabetes using various cut-off points for HbA(1c) and impaired fasting glucose: the Toranomon Hospital Health Management Center Study 4 (TOPICS 4).

AIM: To evaluate various screening criteria for pre-diabetes to identify which combination of impaired fasting glucose and elevated HbA(1c) values performs most effectively in predicting future diabetes in a large cohort of Japanese individuals. METHODS: The study included 4670 men and 1571 women without diabetes (diabetes: fasting plasma glucose ≥ 7.0 mmol/l, HbA(1c) ≥ 48 mmol/mol (≥ 6.5%), or self-reported clinician-diagnosed diabetes). Pre-diabetes was diagnosed by a combination of impaired fasting glucose (fasting plasma glucose 5.6-6.9 mmol/l or 6.1-6.9 mmol/l) and elevated HbA(1c) [39-46 mmol/mol (5.7-6.4%) or 42-46 mmol/mol (6.0-6.4%)]. RESULTS: During a 5-year follow-up, 338 incident cases of diabetes occurred. The combination of HbA(1c) 39-46 mmol/mol (5.7-6.4%) and fasting plasma glucose 5.6-6.9 mmol/l yielded the highest sensitivity (86%) and generated a large population-attributable per cent risk (78%) for predicting development of diabetes. Among individuals classified as having pre-diabetes by any of the four combined criteria, 20.5-32.0% reverted to the normoglycaemic state as having neither elevated HbA(1c) nor impaired fasting glucose at the last follow-up examination. At 5.6 years after the baseline examination, however, pre-diabetic individuals who fulfilled both HbA(1c) 42-46 mmol/mol (6.0-6.4%) and fasting plasma glucose 6.1-6.9 mmol/l had a 100% cumulative risk of developing diabetes. CONCLUSIONS: The combination of HbA(1c) 39-46 mmol/mol (5.7-6.4%) and fasting plasma glucose 5.6-6.9 mmol/l would have the best performance in reducing the likelihood of missing future cases of diabetes. Identifying pre-diabetic individuals who strictly fulfil HbA(1c) 42-46 mmol/mol (6.0-6.4%) and fasting plasma glucose 6.1-6.9 mmol/l would predict definite progression to diabetes.

High normal HbA(1c) levels were associated with impaired insulin secretion without escalating insulin resistance in Japanese individuals: the Toranomon Hospital Health Management Center Study 8 (TOPICS 8).

AIMS: We aimed to characterize the association of insulin resistance, impaired insulin secretion and ß-cell dysfunction in relation to HbA(1c) levels in a non-diabetic range in Japanese individuals without clinically diagnosed diabetes. METHODS: This cross-sectional study included 1444 individuals without a history of outpatient treatment of diabetes or use of insulin or oral hypoglycaemic agents. The homeostasis model assessment of insulin resistance and beta-cell function, insulinogenic index, Matsuda index and disposition index were calculated using data from 75-g oral glucose tolerance tests and compared across quintile (Q) categories of HbA(1c) levels. RESULTS: Fasting plasma glucose and 30-min and 60-min plasma glucose (PG) levels were significantly higher when HbA(1c) exceeded 36 mmol/mol (5.4%). A HbA(1c) concentration of 36-37 mmol/mol (5.4-5.5%) (Q3) was significantly associated with a 15% lower homeostasis model assessment of ß-cell function value and 31% lower insulinogenic index value compared with HbA(1c) ≤ 32 mmol/mol (≤ 5.1%) (Q1) (P <0.01). Further, a HbA(1c) concentration of 38-40 mmol/mol (5.6-5.8%) (Q4) was associated with 17% (P <0.01) and 24% (P <0.05) reductions in those indexes, respectively. However, the homeostasis model assessment of insulin resistance was not significantly elevated and the Matsuda index was not significantly lower unless HbA(1c) exceeded 41 mmol/mol (5.9%). Individuals with HbA(1c) ≥ 41 mmol/mol (≥ 5.9%) (Q5) had a 69% lower disposition index than those with a HbA(1c) concentration of ≤ 32 mmol/mol (≤ 5.1%) (Q1). CONCLUSIONS: Elevated HbA(1c) levels ≥ 41 mmol/mol (≥ 5.9%) were associated with substantial reductions in insulin secretion, insulin sensitivity and ß-cell dysfunction in Japanese individuals not treated for diabetes. High normal HbA(1c) levels of 36-40 mmol/mol (5.4-5.8%) were also associated with impaired insulin secretion without marked insulin resistance in Japanese individuals.

Incidence and progression of diabetic retinopathy in Japanese adults with type 2 diabetes: 8 year follow-up study of the Japan Diabetes Complications Study (JDCS).

AIMS/HYPOTHESIS: The aim of this study was to determine the incidence and progression rates of diabetic retinopathy and their associations in Japanese individuals with type 2 diabetes. METHODS: This is a part of the Japan Diabetic Complications Study (JDCS), a multi-centred randomised trial of type 2 diabetes patients aged 40-70 years with an 8 year follow-up. There were 1,221 patients without diabetic retinopathy at baseline; incidence of diabetic retinopathy was defined as the development of any diabetic retinopathy. There were 410 patients with mild non-proliferative diabetic retinopathy at baseline; progression of diabetic retinopathy was defined as the development of severe non-proliferative diabetic retinopathy or proliferative diabetic retinopathy. We used multivariate proportional Cox hazard models, and generalised additive models were also applied to identify potential threshold effect. RESULTS: The incidence and progression rate of diabetic retinopathy was 38.3/1,000 person-years and 21.1/1,000 person-years, respectively. Higher HbA(1c) (adjusted HR [aHR] per 1% [10.9 mmol/mol] 1.36 [95% CI 1.28-1.45]), longer duration of diabetes (aHR per 5 year period 1.26 [95% CI 1.17-1.35]), higher systolic blood pressure (aHR per +10 mmHg 1.01 [95% CI 1.00-1.02]) and higher body mass index (aHR per 1 kg/m(2) 1.05 [95% CI 1.00-1.09]) were associated with incident diabetic retinopathy. The association between HbA(1c) and incident diabetic retinopathy was linear; the association with duration of diabetes increased rapidly between 5 and 10 years. Higher HbA(1c) was also associated with progression of diabetic retinopathy (aHR per 1% [10.9 mmol/mol] 1.66 [95% CI 1.41-1.96]). CONCLUSIONS: Observed incidence and progression rates of diabetic retinopathy seemed lower than that in western populations. HbA(1c) was the only factor associated with both incidence and progression of diabetic retinopathy. The strength of the association between duration of diabetes and incidence of diabetic retinopathy increased rapidly during a period of 5 to 10 years duration of diabetes. TRIAL REGISTRATION: C000000222 ( www.umin.ac.jp ) FUNDING: This study is supported by the Ministry of Health, Labour and Welfare, Japan.

Low transition rate from normo- and low microalbuminuria to proteinuria in Japanese type 2 diabetic individuals: the Japan Diabetes Complications Study (JDCS).

AIMS/HYPOTHESIS: The aim of the study was to determine the transition rate and factors associated with the progression of normo- and low microalbuminuria to diabetic nephropathy (overt proteinuria). METHODS: For 8 years we prospectively observed 1,558 Japanese patients with type 2 diabetes mellitus whose basal urinary albumin:creatinine ratio (UACR) had been measured as <17.0 mg/mmol at entry. The incidence of nephropathy (UACR >33.9 mg/mmol) was determined by measuring UACR twice a year. RESULTS: Progression to nephropathy occurred in 74 patients. The annual transition rate was 0.67%, and was substantially higher for the low-microalbuminuric group than for the normoalbuminuric group (1.85% and 0.23%, respectively; hazard ratio for the low-microalbuminuric group 8.45, p < 0.01). The hazard ratio for an HbA(1c) of 7-9% or ≥9% was 2.72 (p < 0.01) or 5.81 (p < 0.01) relative to HbA(1c) <7.0%, respectively. In comparison with individuals with a systolic blood pressure (SBP) of <120 mmHg, the hazard ratios for patients with an SBP of 120-140 mmHg or ≥140 mmHg were 2.31 (p = 0.06) and 3.54 (p < 0.01), respectively. Smoking also affected progression to proteinuria (hazard ratio 1.99, p < 0.01). In contrast, 30.3% of the low-microalbuminuric group returned to normoalbuminuria (i.e. were in remission). CONCLUSIONS/INTERPRETATION: These results suggest that if patients with type 2 diabetes mellitus are receiving treatment from diabetologists for hyperglycaemia and hypertension when they are in the early stages of nephropathy (i.e. normo- or low microalbuminuria), their rate of transition to proteinuria is considerably lowered, and that differentiating patients with low microalbuminuria from those with high microalbuminuria might be clinically useful. TRIAL REGISTRATION: UMIN Clinical Trials Registry C000000222.

Low serum potassium levels and risk of type 2 diabetes: the Toranomon Hospital Health Management Center Study 1 (TOPICS 1).

AIMS/HYPOTHESIS: Evidence has suggested that low serum potassium concentrations decrease insulin secretion, leading to glucose intolerance, and that hypokalaemia induced by diuretics increases the risk for diabetes in hypertensive individuals. However, no prospective study has investigated the association between serum potassium and the development of type 2 diabetes in a healthy cohort comprised of Asian individuals not being administered antihypertensive medications. This study aimed to investigate whether low serum potassium is associated with increased risk of type 2 diabetes in apparently healthy Japanese men. METHODS: We followed 4,409 Japanese men with no history of diabetes, use of antihypertensives, renal dysfunction or liver dysfunction (mean ± SD age, 48.4 ± 8.4 years). Cox proportional hazards regression was used to estimate HRs for incident diabetes (fasting plasma glucose level ≥ 7.0 mmol/l, HbA(1c) ≥ 6.5% or self-reported) including serum potassium concentration as either a categorical or a continuous variable. RESULTS: During a 5 year follow-up, 250 individuals developed type 2 diabetes. The lowest tertile of serum potassium (2.8-3.9 mmol/l) was independently associated with the development of diabetes after adjustment for known predictors (HR 1.57 [95% CI, 1.15-2.15]) compared with the highest tertile (4.2-5.4 mmol/l). Every 0.5 mmol/l lower increment in the baseline serum potassium level was associated with a 45% (12-87%) increased risk of diabetes. CONCLUSIONS/INTERPRETATION: Mild to moderately low serum potassium levels, within the normal range and without frank hypokalaemia, could be predictive of type 2 diabetes in apparently healthy Japanese men.

Low incidence of cardiovascular events in Japanese patients with Type 2 diabetes in primary care settings: a prospective cohort study (JDDM 20).

AIMS: To investigate whether a reduced incidence of cardiovascular disease in Type 2 diabetes can be achieved in a newly recruited cohort following the recently advanced concept of multifactorial treatment and followed in primary care settings as compared with earlier cohorts. METHODS: A prospective study was performed in primary care settings at multiple clinics nationwide in the Japan Diabetes Clinical Data Management (JDDM) study group. Subjects were 2984 patients with Type 2 diabetes without prevalent cardiovascular disease. The main outcome measure was the first event of non-fatal or fatal coronary heart disease, ischaemic stroke or peripheral artery disease, and the incidence was compared with other representative cohorts. RESULTS: There were 90 cardiovascular events over 10,827 person-years of follow-up with a dropout rate of 6%. The incidences (per 1000 person-years, 95% confidence interval) of composite, coronary heart disease, ischaemic stroke and peripheral artery disease in the JDDM study were 8.3 (6.6-10.0), 4.4 (3.2-5.6), 3.1 (2.1-4.2), and 0.7 (0.2-1.2), respectively. Each incidence was lowest in the JDDM study compared with other cohorts (P < 0.01 vs. each cohort). In the JDDM study, significant variables predictive of the occurrence of a cardiovascular event were age, duration of diabetes, HbA(1c), HDL cholesterol and urinary albumin. CONCLUSION: The novel finding of low cardiovascular disease occurrence in this study may be conferred by the feasibility at primary care settings for providing patients with Type 2 diabetes with favourable control of blood glucose, blood pressure and lipids, coupled with unique ethnicity/country factors.