Obesity and type 2 diabetes in Japanese patients

Diabetes with COVID-19 was a significant risk factor for mortality, mechanical ventilation, and renal replacement therapies: A multicenter retrospective study in Japan

We conducted a multicenter retrospective cohort study across 38 hospitals in Chiba, Japan, between February 1, 2020 and November 31, 2021 to investigate the effect of coronavirus disease 2019 (COVID-19) on patients with diabetes mellitus receiving inpatient care. We collected inpatient medical data through Diagnosis procedure combination (DPC), the diagnoses and payment system of medical insurance, from each hospital. We excluded patients younger than 18 years, those who were pregnant, and those who had diabetes but were not treated with diabetic medication. A total of 10,776 patients were included: 7,679 in the non-diabetic (control) group and 3,097 in the diabetic group. Patients in the diabetic group were older and had a higher body mass index (BMI) than those in the control group. In the diabetes group, 88.4% of the patients were treated with insulin therapy and 44.2% were treated with oral hypoglycemic agents. The length of hospital days was significantly longer in the diabetes group. The in-hospital mortality rate was significantly higher especially between 50 and 59 years old. The rates of in-hospital mortality, mechanical ventilation, intensive care unit (ICU) admission, renal replacement therapies such as hemodialysis (HD), and continuous hemodiafiltration (CHDF) were all higher, even after adjusting for age, sex, BMI, and ambulance use. In conclusion, diabetes was a significant risk factor of the severe clinical outcomes especially for in-hospital mortality, mechanical ventilation usage, ICU admission, HD, and CHDF in Japan.

Japan Diabetes Complications Study: Revisiting one of the first large-scale clinical studies in East Asians with diabetes

This review highlights the significance of the Japan Diabetes Complications Study (JDCS), one of the earliest large-scale studies of people with type 2 diabetes outside Europe and the United States, in understanding type 2 diabetes mellitus among East Asian populations, particularly in Japan. Historically, large-scale clinical studies on type 2 diabetes mellitus have predominantly focused on Western populations, despite East Asians comprising the largest proportion of diabetic patients globally. The JDCS, which was initiated in 1996, enrolled 2,033 Japanese type 2 diabetes mellitus patients. It aimed to evaluate the effects of intensive lifestyle interventions on diabetic complications. The study demonstrated that lifestyle-focused interventions significantly reduced the risk of stroke and other complications compared to conventional treatment. Key findings of its sub-analyses include the unique characteristics of Japanese patients with type 2 diabetes mellitus, such as their lower body mass index (BMI) compared to Western counterparts and a stronger association between even modest BMI increases and beta cell dysfunction. Additionally, the JDCS provided insights into the risk factors for nephropathy, retinopathy, and macrovascular complications, emphasizing the importance of controlling blood pressure, glycemia, and lifestyle factors. The study also explored the impact of diet, exercise, and mental health on diabetic outcomes, revealing the protective effects of physical activity and a balanced diet, while highlighting the risks associated with high salt intake and depression. A risk prediction model tailored to Japanese patients was also developed. Overall, this study made a significant contribution to the evidence-based management of type 2 diabetes mellitus in East Asia.

Dietary potassium intake and its interaction with sodium intake on risk of developing cardiovascular disease in persons with type 2 diabetes: The Japan Diabetes Complication and its Prevention Prospective study (JDCP study 12)

AIMS

Many guidelines recommend increases in potassium intake. However, the relationship of dietary potassium intake with incident cardiovascular disease (CVD) has not been examined in those with type 2 diabetes (T2DM), including sodium acting antagonistically with potassium. We investigated these relationships in Japanese patients with T2DM.

MATERIALS AND METHODS

The investigation was part of the JDCP study, a nationwide prospective study begun in 2007. Analysed were 1477 persons with T2DM, 40-75 years of age, who completed a brief-type, self-administered Diet History Questionnaire at baseline. Primary outcome was a CVD event during the follow-up median 7 years (3.9-8.1 years). Hazard ratios (HRs) for CVD were estimated by Cox regression adjusted for confounders of daily potassium intake categorized by tertiles. Tertiles of sodium intake were also analysed.

RESULTS

Mean daily potassium intake in tertiles was 1877, 2627 and 3532 mg, respectively, and significant associations were not shown between potassium intake and incidence of CVD. When HRs for CVD were stratified for potassium intake in tertiles (reference group, bottom tertile) and sodium intake (reference group, bottom tertile), potassium intake in the bottom tertile and sodium intake in the second and top tertiles were associated with significantly elevated HR for CVD (2.79 [1.02-7.63] and 3.92 [1.30-11.79], respectively).

CONCLUSIONS

Low potassium intake in conjunction with high sodium intake was significantly associated with increased incident CVD in persons with T2DM. However, CVD incidence was not related to high potassium intake, regardless of sodium intake.

Importance of Blood Glucose Measurement for Predicting the Prognosis of Long COVID: A Retrospective Study in Japan

Purpose: The present study aimed to clarify the effects of a hyperglycemic condition on the clinical consequences of long COVID. Methods: Among 643 patients who visited the outpatient clinic of our hospital from February 2021 to September 2023, long COVID patients were classified into a hyperglycemic (HG) group with casual blood glucose levels above 140 mg/dL and a normoglycemic (NG) group. The patients' backgrounds, clinical symptoms, health status including the QOL evaluation scale (EQ-5D-5L), self-rating depression scale (SDS), and F-scale questionnaire (FSSG), blood test data, and recovery periods were analyzed. Results: The NG group included 607 patients with long COVID and the HG group included 36 patients with long COVID. Patients in the HG group were older than those in the NG group (55 vs. 41 years; p < 0.001) and included a larger percentage of males (67% vs. 44%; p = 0.009). The HG group had a larger percentage of patients with moderate-to-severe conditions in the acute infection phase (28% vs. 12%; p = 0.008), a higher BMI (25 vs. 22 kg/m2; p < 0.001), higher blood pressure (138/81 vs. 122/72 mmHg; p < 0.001), and a larger percentage of patients with an alcohol drinking habit (53% vs. 34%; p = 0.031). Long COVID symptoms and self-rated scales were not differed between the two groups; however, the laboratory data showed that liver and renal functions and metabolic data were significantly worse in the HG group. Although there was no apparent difference between the two groups in duration from the infection to the first visit, the HG group had a significantly longer period of recovery from long COVID (median period of 421 vs. 294 days; p = 0.019). Conclusion: A hyperglycemic state associated with other lifestyle-related diseases is associated with the prolongation of recovery from long COVID.

Efficacy of Human Recombinant Growth Hormone in Females of a Non-Obese Hyperglycemic Mouse Model after Birth with Low Birth Weight

We examined whether the administration of growth hormone (GH) improves insulin resistance in females of a non-obese hyperglycemic mouse model after birth with low birth weight (LBW), given that GH is known to increase muscle mass. The intrauterine Ischemia group underwent uterine artery occlusion for 15 min on day 16.5 of gestation. At 4 weeks of age, female mice in the Ischemia group were divided into the GH-treated (Ischemia-GH) and non-GH-treated (Ischemia) groups. At 8 weeks of age, the glucose metabolism, muscle pathology, and metabolome of liver were assessed. The insulin resistance index improved in the Ischemia-GH group compared with the Ischemia group (p = 0.034). The percentage of type 1 muscle fibers was higher in the Ischemia-GH group than the Ischemia group (p < 0.001); the muscle fiber type was altered by GH. In the liver, oxidative stress factors were reduced, and ATP production was increased in the Ischemia-GH group compared to the Ischemia group (p = 0.014), indicating the improved mitochondrial function of liver. GH administration is effective in improving insulin resistance by increasing the content of type 1 muscle fibers and improving mitochondrial function of liver in our non-obese hyperglycemic mouse model after birth with LBW.

Body mass index stratification optimizes polygenic prediction of type 2 diabetes in cross-biobank analyses

Type 2 diabetes (T2D) shows heterogeneous body mass index (BMI) sensitivity. Here, we performed stratification based on BMI to optimize predictions for BMI-related diseases. We obtained BMI-stratified datasets using data from more than 195,000 individuals (nT2D = 55,284) from BioBank Japan (BBJ) and UK Biobank. T2D heritability in the low-BMI group was greater than that in the high-BMI group. Polygenic predictions of T2D toward low-BMI targets had pseudo-R2 values that were more than 22% higher than BMI-unstratified targets. Polygenic risk scores (PRSs) from low-BMI discovery outperformed PRSs from high BMI, while PRSs from BMI-unstratified discovery performed best. Pathway-specific PRSs demonstrated the biological contributions of pathogenic pathways. Low-BMI T2D cases showed higher rates of neuropathy and retinopathy. Combining BMI stratification and a method integrating cross-population effects, T2D predictions showed greater than 37% improvements over unstratified-matched-population prediction. We replicated findings in the Tohoku Medical Megabank (n = 26,000) and the second BBJ cohort (n = 33,096). Our findings suggest that target stratification based on existing traits can improve the polygenic prediction of heterogeneous diseases.

Mechanism of muscle atrophy in a normal-weight rat model of type 2 diabetes established by using a soft-pellet diet

Dietary factors such as food texture affect feeding behavior and energy metabolism, potentially causing obesity and type 2 diabetes. We previously found that rats fed soft pellets (SPs) were neither hyperphagic nor overweight but demonstrated glucose intolerance, insulin resistance, and hyperplasia of pancreatic β-cells. In the present study, we investigated the mechanism of muscle atrophy in rats that had been fed SPs on a 3-h time-restricted feeding schedule for 24 weeks. As expected, the SP rats were normal weight; however, they developed insulin resistance, glucose intolerance, and fat accumulation. In addition, skeletal muscles of SP rats were histologically atrophic and demonstrated disrupted insulin signaling. Furthermore, we learned that the muscle atrophy of the SP rats developed via the IL-6-STAT3-SOCS3 and ubiquitin-proteasome pathways. Our data show that the dietary habit of consuming soft foods can lead to not only glucose intolerance or insulin resistance but also muscle atrophy.

Trk-fused gene plays a critical role in diet-induced adipose tissue expansion and is also involved in thyroid hormone action

Mutations in the Trk-fused gene (TFG) cause hereditary motor and sensory neuropathy with proximal dominant involvement, which reportedly has high co-incidences with diabetes and dyslipidemia, suggesting critical roles of the TFG in metabolism as well. We found that TFG expression levels in white adipose tissues (WATs) were elevated in both genetically and diet-induced obese mice and that TFG deletion in preadipocytes from the stromal vascular fraction (SVF) markedly inhibited adipogenesis. To investigate its role in vivo, we generated tamoxifen-inducible adipocyte-specific TFG knockout (AiTFG KO) mice. While a marked down-regulation of the peroxisome proliferator-activated receptor gamma target, de novo lipogenesis (DNL), and mitochondria-related gene expressions were observed in subcutaneous WAT (scWAT) from AiTFG KO mice, these effects were blunted in SVF-derived adipocytes when the TFG was deleted after differentiation into adipocytes, implying cell nonautonomous effects. Intriguingly, expressions of thyroid hormone receptors, as well as carbohydrate responsive element-binding protein β, which mediates the metabolic actions of thyroid hormone, were drastically down-regulated in scWAT from AiTFG KO mice. Reduced DNL and thermogenic gene expressions in AiTFG KO mice might be attributable to impaired thyroid hormone action in vivo. Finally, when adipocyte TFG was deleted in either the early or the late phase of high-fat diet feeding, the former brought about an impaired expansion of epididymal WAT, whereas the latter caused prominent adipocyte cell death. TFG deletion in adipocytes markedly exacerbated hepatic steatosis in both experimental settings. Collectively, these observations indicate that the TFG plays essential roles in maintaining normal adipocyte functions, including an enlargement of adipose tissue, thyroid hormone function, and thermogenic gene expressions, and in preserving hypertrophic adipocytes.

Relationship between the magnitude of body mass index reductions and remission in patients with type 2 diabetes in real world settings: Analysis of nationwide patient registry in Japan (JDDM74)

AIMS

To determine the association between the magnitude of weight loss and incidence of remission according to baseline characteristics in patients with diabetes in clinical settings.

METHODS

In total, 39 676 Japanese patients with type 2 diabetes aged ≥18 years with glycated haemoglobin (HbA1c) ≥6.5% and/or glucose-lowering drug prescription were identified from databases of specialists' clinics from 1989 and followed until September 2022. Remission was diagnosed as maintaining HbA1c <6.5% at least 3 months after cessation of a glucose-lowering drug. Factors associated with remission were evaluated by logistic regression analysis according to weight change in 1 year (i.e. ≥10%, 7.0-9.9%, 3.0-6.9% reduction, <3% change and ≥3.0% increase).

RESULTS

During the study period, 3454 remissions occurred. The rates of remission were higher in the group with the greatest reduction of body mass index (BMI) in any category examined (i.e. baseline BMI, HbA1c, duration of diabetes and treatment). The incidences of remission per 1000 person-years were about 25 and 50, respectively, for those with BMI ≥22.5 and reductions in BMI of 7.0-9.9% and ≥10% in 1 year. Remissions per 1000 person-years were 99.2 and 91.8, respectively, for those with baseline HbA1c of 6.5-6.9 and a 10% BMI reduction and those not taking glucose-lowering drugs accompanied by a 10% BMI reduction.

CONCLUSIONS

Modest weight losses of 3.0-7.9% were significantly associated with remission, but a minimum of 10% weight loss would be required in addition to an early diagnosis to achieve a 10% remission rate in clinical settings. Our results implied that remission may be expected with a relatively lower BMI in an Asian population compared with that was reported in Western populations if accompanied by weight loss.

Eating behaviors and incident cardiovascular disease in Japanese people: The population-based Panasonic cohort study 14

Evidence on common eating behaviors to support the prevention of cardiovascular disease (CVD) in Japanese people is insufficient. This retrospective cohort study aimed to investigate the association of diet behaviors (e.g., skipping breakfast, eating speed, snack after dinner, and alcohol consumption) with incident CVD in Japanese individuals. Employees of Panasonic Corporation who underwent the annual health checkups and without a history of CVD at baseline were enrolled. The main outcome was incident 3-point major adverse cardiovascular events (MACE). The secondary outcomes were incident coronary artery disease (CAD) and stroke. To assess the effect of BMI, the subgroup analysis was conducted. In total, 132,795 participants were included. Overall, 3,115, 1,982, and 1,165 participants developed 3-point MACE, CAD, and stroke, respectively. Skipping breakfast (HR: 1.13, 95% CI: 1.03-1.23) and fast eating (HR: 1.23, 95% CI: 1.04-1.47) were associated with 3-point MACE in the participants overall. Skipping breakfast (HR: 1.23, 95% CI: 1.10-1.37) and fast eating (HR: 1.38, 95% CI: 1.12-1.71) were also associated with 3-point MACE in participants with BMI < 25 kg/m². In contrast, in participants with BMI ≥ 25 kg/m², these associations were not detectable (P value for the interaction between subgroups = 0.09 [skipping breakfast] and 0.03 [fast eating], respectively). The diet behavior is a potential risk factor of incident CVD in Japanese people, particularly in those with BMI < 25 kg/m².

Incidence and predictors of remission and relapse of type 2 diabetes mellitus in Japan: Analysis of a nationwide patient registry

AIMS

To determine the incidence of remission and 1-year relapse from remission and associated factors in patients with type 2 diabetes.

MATERIALS AND METHODS

A total of 48 320 Japanese patients with type 2 diabetes aged ≥18 years, with glycated haemoglobin (HbA1c) levels ≥48 mmol/mol (6.5%) and/or glucose-lowering drug prescription, were identified from databases of specialist clinics from 1989 and followed until September 2022. Remission was defined as HbA1c <48 mmol/mol at least 3 months after cessation of a glucose-lowering drug. Relapse was defined as failure to maintain remission for 1 year. Factors associated with remission and relapse were evaluated by logistic regression analysis.

RESULTS

The overall incidence of remissions per 1000 person-years was 10.5, and for those with HbA1c levels of 48 to 53 mmol/mol (6.5% to 6.9%), those taking no glucose-lowering drugs at baseline, and those with a ≥10% body mass index (BMI) reduction in 1 year, it was 27.8, 21.7 and 48.2, respectively. Shorter duration, lower baseline HbA1c, higher baseline BMI, higher BMI reduction at 1 year, and no glucose-lowering drugs at baseline were significantly associated with remission. Among 3677 persons with remission, approximately two-thirds (2490) relapsed within 1 year. Longer duration, lower BMI at baseline, and lower BMI reduction at 1 year were significantly associated with relapse.

CONCLUSIONS

The results showed that the incidence of remission and predictors of relapse, especially baseline BMI, might differ greatly between East Asian and Western populations. Furthermore, the relationships of BMI reduction with remission and relapse may be greater in East Asian than in Western populations, implying ethnic differences in returning from overt hyperglycaemia to nearly normal glucose levels.

Association of complication of type 2 diabetes mellitus with hemodynamics and exercise capacity in patients with heart failure with preserved ejection fraction: a case-control study in individuals aged 65-80 years

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a frequently observed complication in patients with heart failure with preserved ejection fraction (HFpEF). Although a characteristic finding in such patients is a decrease in objective exercise capacity represented by peak oxygen uptake (peakVO₂), exercise capacity and its predictors in HFpEF with T2DM remain not clearly understood. This case-control study aimed to investigate the association between exercise capacity and hemodynamics indicators and T2DM comorbidity in patients with HFpEF aged 65-80 years.

METHODS

Ninety-nine stable outpatients with HFpEF and 50 age-and-sex-matched controls were enrolled. Patients with HFpEF were classified as HFpEF with T2DM (n = 51, median age, 76 years) or without T2DM (n = 48, median age, 76 years). The peakVO₂ and ventilatory equivalent versus carbon dioxide output slope (VE vs VCO₂ slope) were measured by cardiopulmonary exercise testing. The peak heart rate (HR) and peak stroke volume index (SI) were measured using impedance cardiography, and the estimated arteriovenous oxygen difference (peak a-vO₂ diff) was calculated with Fick's equation. The obtained data were compared among the three groups using analysis of covariance adjusted for the β-blocker medication, presence or absence of sarcopenia, and hemoglobin levels in order to determine the T2DM effects on exercise capacity and hemodynamics in patients with HFpEF.

RESULTS

In HFpEF with T2DM compared with HFpEF without T2DM and the controls, the prevalence of sarcopenia, chronotropic incompetence, and anemia were significantly higher (p < 0.001). The peakVO₂ (Controls 23.5 vs. without T2DM 15.1 vs. with T2DM 11.6 mL/min/kg), peak HR (Controls 164 vs. without T2DM 132 vs. with T2DM 120 bpm/min), peak a-vO₂ (Controls 13.1 vs without T2DM 10.6 vs with T2DM 8.9 mL/100 mL), and VE vs VCO₂ slope (Controls 33.2 vs without T2DM 35.0 vs with T2DM 38.2) were significantly worsened in patients with HFpEF with T2DM (median, p < 0.001). There was no significant difference in peak SI among the three groups.

CONCLUSIONS

Our results suggested that comorbid T2DM in patients with HFpEF may reduce exercise capacity, HR response, peripheral oxygen extraction, and ventilation efficiency. These results may help identify cardiovascular phenotypes of HFpEF complicated with T2DM and intervention targets for improving exercise intolerance.

Association between abdominal obesity and diabetic retinopathy in patients with diabetes mellitus: A systematic review and meta-analysis

OBJECTIVE

Previous studies have reported different opinions regarding the association between abdominal obesity and diabetic retinopathy (DR) in patients with diabetes mellitus (DM). In this study, we aimed to investigate this problem through a systematic review and meta-analysis to provide a basis for clinical interventions.

METHODS

A comprehensive search was conducted in the PubMed, Embase, and Web of Science databases up to May 1, 2022, for all eligible observational studies. Standardized mean differences (SMD) and 95% confidence intervals (CI) were evaluated using a random-effects model in the Stata software. We then conducted, publication bias assessment, heterogeneity, subgroup and sensitivity analyses.

RESULTS

A total of 5596 DR patients and 17907 non-DR patients were included from 24 studies. The results of the meta-analysis of abdominal obesity parameters showed statistically significant differences between DR and non-DR patients in both type 1 and type 2 diabetes. Waist circumference (WC) was higher in patients with DR than in the non-DR patients. In the waist-hip ratio (WHR) subgroup, the level of WHR was higher in patients with DR than that in non-DR patients. The association between abdominal obesity and mild to moderate nonproliferative DR or vision-threatening DR groups did not show any statistical difference. Subgroup analysis according to ethnicity showed that Caucasians had higher levels of combined abdominal obesity parameters than Asians.

CONCLUSION

We found that abdominal obesity measured by WC and WHR is associated with DR in patients with type 1 and type 2 diabetes. This association is stronger in Caucasians than in Asians, where isolated abdominal obesity might be more related to DR. However, no correlation was found between abdominal obesity and varying degrees of diabetic retinopathy. Further prospective cohort studies with larger sample sizes are yet to be conducted to clarify our findings.

Year-long effects of COVID-19 restrictions on glycemic control and body composition in patients with glucose intolerance in Japan: A single-center retrospective study

Aims/Instruction

During the coronavirus disease 2019 (COVID‐19) pandemic, the lockdowns in Europe raised concerns about negative effects on glycemic control and body composition in patients with diabetes. In Japan, voluntary‐based restrictions were imposed as the declaration of a state of emergency (DSE), whose metabolic consequences have not been fully investigated. We carried out a single‐center retrospective study to evaluate changes in glycemic control and body composition in outpatients with glucose intolerance after the DSE.

Materials and Methods

We enrolled outpatients with glucose intolerance: (i) for whom longitudinal data about body composition were available; (ii) who participated in dietary follow up with nutritionists; and (iii) whose laboratory data included glycated hemoglobin (HbA1c) levels before and after the DSE.

Results

Among 415 patients, we found no significant changes in HbA1c overall after the DSE. Bodyweight and fat mass increased significantly, whereas skeletal mass decreased significantly. HbA1c changes after the DSE were significantly correlated with changes in bodyweight and fat mass. In 128 patients whose HbA1c levels increased ≥0.3%, changes in bodyweight and fat mass were significantly larger than those in the other 287 patients. With regard to lifestyle changes, increased snacking was likely to worsen glycemic control (odds ratio 1.76, P = 0.036).

Conclusions

COVID‐19 restrictions in Japan had unfavorable metabolic consequences for patients with glucose intolerance, highlighted by increased bodyweight and body fat, and decreased skeletal muscle. In addition, lifestyle changes, such as increased snacking, might worsen glycemic control. Clinical attention and interventions are required to prevent such metabolic changes.

A Non-Obese Hyperglycemic Mouse Model that Develops after Birth with Low Birthweight

The number of low birthweight (LBW) infants weighing below 2500 g has not decreased in Japan. This study aimed to develop an adult non-obese hyperglycemic mouse model born with LBW to study the pathogenesis. At 16.5 days of gestation, transient intrauterine ischemia (blocked blood flow in both uterine arteries for 15 min) was performed in a subgroup of pregnant mice (group I). Non-occluded dams were used as sham controls (group C). After birth, female pups in each group were weaned at 4 weeks of age and reared on the normal diet until 8 weeks of age (n = 7). Fasting blood glucose levels, serum immunoreactive insulin (IRI), and body composition were then measured. Metabolite analyses was performed on the liver tissues. Birthweight was significantly lower in group I compared with group C. Pups from group I remained underweight with low fat-free mass and showed hyperglycemia with high serum IRI and homeostasis model assessment of insulin resistance levels, indicating insulin resistance. Metabolite analyses showed significantly reduced adenosine triphosphate and nicotinamide adenine dinucleotide production and increased lactic acid in group I. The pathogenesis of our non-obese hyperglycemic mouse model may be due to increased myogenic insulin resistance based on mitochondrial dysfunction and reduced lean body mass.

Safety and effectiveness of empagliflozin according to body mass index in Japanese patients with type 2 diabetes: a subgroup analysis of a 3-year post-marketing surveillance study

BACKGROUND

Empagliflozin, a glucose-lowering drug licensed for type 2 diabetes (T2D), demonstrated tolerability and effectiveness overall in a post-marketing surveillance (PMS) study in Japan. However, the impact of body mass index (BMI) is unclear.

RESEARCH DESIGN AND METHODS

This was a prespecified sub-analysis of the prospective, 3-year, PMS study of empagliflozin in Japan where the primary endpoint was adverse drug reactions (ADRs). We evaluated results according to BMI.

RESULTS

We enrolled 7931 T2D patients treated with empagliflozin. Baseline mean age was 58.7 years; 63.01% were male. Baseline BMI was <20 kg/m² in 2.06% of patients, while 21.28%, 37.35%, and 24.97% had BMI 20-<25, 25-<30 and ≥30 kg/m², respectively. ADRs occurred in 19 (11.66%), 203 (12.03%), 411 (13.88%), and 295 (14.90%) patients with BMI <20, 20-<25, 25-<30 and ≥30 kg/m², respectively. Excessive/frequent urination was the most frequent ADR of special interest in all BMI subgroups except 20-<25 kg/m² (urinary tract infection). Mean change in glycated hemoglobin from baseline was -0.75%, with similar magnitude across BMI subgroups. Body-weight reduction seemed dependent on BMI, with almost no change in the <20 kg/m² subgroup.

CONCLUSIONS

Empagliflozin appeared well tolerated and effective in Japanese T2D patients regardless of BMI, although the number of patients with BMI <20 kg/m² was small in this study.

Dietary intake and physical activity in Japanese patients with type 2 diabetes: the Japan Diabetes Complication and its Prevention prospective study (JDCP study 8)

Medical nutrition therapy and exercise therapy are the cornerstones of treatment for patients with type 2 diabetes; however, there has not been a nationwide study on the actual dietary intake and physical activity status of patients since the 2000s. We aimed to clarify this in Japanese patients with type 2 diabetes using data from the Japan Diabetes Complication and its Prevention prospective (JDCP), a nationwide study launched in 2007. A total of 1992 patients with type 2 diabetes, aged 40-75 years, completed either the Brief-type, self-administered Diet History Questionnaire (1643 patients) or International Physical Activity Questionnaire (1834 patients), and their data were analyzed in this study. Mean daily energy intake for all participants was 1686.8 kcal/day, and the mean proportions of carbohydrate, protein, and fat comprising total energy intake were 60.2, 16.2, and 23.6%, respectively. The patients in this study had similar energy and nutrient intake status to patients in the 1996 Japan Diabetes Complications Study; however, Japanese patients still had higher carbohydrate and lower fat consumption than patients with diabetes in Western countries. The physical activity questionnaire reported that 31.0% of patients did not have exercise habits; this was particularly noticeable in female patients and patients under the age of 65. BMI increased from 22.7 to 24.1 kg/m² in men and 23.2 to 24.8 kg/m² in women from 1996 to 2007, respectively. Further research is required to investigate how dietary intake and physical activity associates with the risk of developing complications in type 2 diabetes patients.

Psychiatric behavioral effect and characteristics of type 2 diabetes mellitus on Japanese patients with Prader-Willi syndrome: a preliminary retrospective study

OBJECTIVES

In recent years, research on behavioral and psychiatric problems of adults with Prader-Willi syndrome (PWS) has gained attention. However, no report is available regarding the relationship between psychiatric illness and type 2 diabetes mellitus (T2DM) in patients with PWS. Therefore, we evaluated a behavioral assessment to address the lack of data on the association between psychiatric behavior and T2DM.

METHODS

This was a retrospective single-center study of patients with PWS. Patients with PWS whose blood tests were performed in our hospital between January 2018 and December 2019 and aged >10 years were included. We evaluated the data, including the behavioral patterns of Japanese PWS patients with T2DM.

RESULTS

Overall, 114 patients were evaluated; 33 patients (28.9%) developed T2DM. The age of T2DM onset was 18.0 years (interquartile range [IQR], 14.6-21.4 years). The median body mass index at T2DM onset was 33.7 kg/m² (IQR, 30.0-37.4 kg/m²). Between-group comparisons of the intelligence quotient, Food-Related Problem Questionnaire (FRPQ), and Japanese versions of the Short Sensory Profile and Aberrant Behavior Checklist showed a significant difference only in FRPQ scores (p=0.003).

CONCLUSIONS

The occurrence of T2DM among Japanese patients with PWS remains high. Only the FRPQ was significantly different between the T2DM and the non-T2DM group.

Risk Classification for Metabolic Syndrome and the Incidence of Cardiovascular Disease in Japan With Low Prevalence of Obesity: A Pooled Analysis of 10 Prospective Cohort Studies

Background It is uncertain whether risk classification under the nationwide program on screening and lifestyle modification for metabolic syndrome captures well high-risk individuals who could benefit from lifestyle interventions. We examined the validity of risk classification by linking the incidence of cardiovascular disease (CVD). Methods and Results Individual-level data of 29 288 Japanese individuals aged 40 to 74 years without a history of CVD from 10 prospective cohort studies were used. Metabolic syndrome was defined as the presence of high abdominal obesity and/or overweight plus risk factors such as high blood pressure, high triglyceride or low high-density lipoprotein cholesterol levels, and high blood glucose levels. The risk categories for lifestyle intervention were information supply only, motivation-support intervention, and intensive support intervention. Sex- and age-specific hazard ratios and population attributable fractions of CVD, which were also further adjusted to consider non-high density lipoprotein cholesterol levels, were estimated with reference to nonobese/overweight individuals, using Cox proportional hazard regression. Since the reference category included those with risk factors, we set a supernormal group (nonobese/overweight with no risk factor) as another reference. We documented 1023 incident CVD cases (565 men and 458 women). The adjusted CVD risk was 60% to 70% higher in men and women aged 40 to 64 years receiving an intensive support intervention, and 30% higher in women aged 65 to 74 years receiving a motivation-support intervention, compared with nonobese/overweight individuals. The population attributable fractions in men and women aged 40 to 64 years receiving an intensive support intervention were 17.7% and 6.6%, respectively, while that in women aged 65 to 74 years receiving a motivation-support intervention was 9.4%. Compared with the supernormal group, nonobese/overweight individuals with risk factors had similar hazard ratios and population attributable fractions as individuals with metabolic syndrome. Conclusions Similar CVD excess and attributable risks among individuals with metabolic syndrome components in the absence and presence of obesity/overweight imply the need for lifestyle modification in both high-risk groups.

Metabolic Syndrome and Sarcopenia

Skeletal muscle is a major organ of insulin-induced glucose metabolism. In addition, loss of muscle mass is closely linked to insulin resistance (IR) and metabolic syndrome (Met-S). Skeletal muscle loss and accumulation of intramuscular fat are associated with a variety of pathologies through a combination of factors, including oxidative stress, inflammatory cytokines, mitochondrial dysfunction, IR, and inactivity. Sarcopenia, defined by a loss of muscle mass and a decline in muscle quality and muscle function, is common in the elderly and is also often seen in patients with acute or chronic muscle-wasting diseases. The relationship between Met-S and sarcopenia has been attracting a great deal of attention these days. Persistent inflammation, fat deposition, and IR are thought to play a complex role in the association between Met-S and sarcopenia. Met-S and sarcopenia adversely affect QOL and contribute to increased frailty, weakness, dependence, and morbidity and mortality. Patients with Met-S and sarcopenia at the same time have a higher risk of several adverse health events than those with either Met-S or sarcopenia. Met-S can also be associated with sarcopenic obesity. In this review, the relationship between Met-S and sarcopenia will be outlined from the viewpoints of molecular mechanism and clinical impact.

Secular Trends in Dietary Intake over a 20-Year Period in People with Type 2 Diabetes in Japan: A Comparative Study of Two Nationwide Registries; Japan Diabetes Complications Study (JDCS) and Japan Diabetes Clinical Data Management Study (JDDM)

Background: In order to provide effective dietary guidance, it is necessary to consider dietary intake, which can change over time. This study analyzed changes in the diet of Japanese patients with type 2 diabetes over a 20-year period. Methods: We compared the results of two dietary surveys that used the food frequency questionnaire format. The first was conducted in 1996 by the Japan Diabetes Complications Study (JDCS) (n = 1509; males 53.3%), and the second in 2014–2018 by the Japan Diabetes Clinical Data Management Study (JDDM) (n = 1145; males 65.6%). Both are nationwide representative registries of outpatients with type 2 diabetes in Japan. Results: Over a 20-year period, both men and women with type 2 diabetes had a significant increase in body mass index (BMI). Nonetheless, there was only a small change in energy intake. Conversely, there was a significant increase in fat intake and thus in the fat-to-energy ratio. With regard to food groups, there was a significant increase in meat intake and a decrease in the intake of fish, soybeans/soy products, vegetables, and fruits, with a particularly significant decrease in vegetables. Conclusions: Even in Japan, an industrialized country with a stable socioeconomic environment, there were many significant changes in the dietary intake of patients with type 2 diabetes over the 20-year period.

Developing a health economic model for Asians with type 2 diabetes based on the Japan Diabetes Complications Study and the Japanese Elderly Diabetes Intervention Trial

INTRODUCTION

Cost-effectiveness analyses are becoming increasingly important in Japan following the introduction of a health technology assessment scheme. The study objective was to develop an economic model to evaluate the cost-effectiveness of two interventions for type 2 diabetes in a Japanese population.

RESEARCH DESIGN AND METHODS

The Japan Diabetes Complications Study/Japanese Elderly Diabetes Intervention Trial risk engine (JJRE) Cost-Effectiveness Model (JJCEM) was developed, incorporating validated risk equations in Japanese patients with type 2 diabetes from the JJRE. Weibull regression models were developed for progression of the model outcomes, and a targeted literature review was performed to inform default values for utilities and costs. To illustrate outcomes, two simulated analyses were performed in younger (aged 40 years) and older (aged 80 years) Japanese populations, comparing a hypothetical treatment with placebo.

RESULTS

The model considers a population based on user-defined values for 11 baseline characteristic parameters and simulates rates of diabetic complications over a defined time horizon. Costs, quality-adjusted life years, and an incremental cost-effectiveness ratio are estimated. The model provides disaggregated results for two competing interventions, allowing visualization of the key drivers of cost and utility. A scatterplot of simulations and cost-effectiveness acceptability curve are generated for each analysis.

CONCLUSIONS

This is the first cost-effectiveness model for East Asian patients with type 2 diabetes, developed using Japan-specific risk equations. This population constitutes the largest share of the global population with diabetes, making this model highly relevant. The model can be used to evaluate the cost-effectiveness of anti-diabetic interventions in patients with type 2 diabetes in Japan and other East Asian populations.

Efficacy and safety of antipsychotic treatments for schizophrenia: A systematic review and network meta-analysis of randomized trials in Japan

BACKGROUND

We examined the efficacy and safety of using antipsychotic medication for schizophrenia using only randomized trials of antipsychotic for schizophrenia conducted in Japan to avoid the biological and environmental heterogeneities caused by pooling data from various races and ethnicities.

METHODS

We searched for eligible studies on Embase, PubMed, and CENTRAL. Primary outcomes were improvement in Positive and Negative Syndrome Scale total score (PANSS-T) and all-cause discontinuation. Other outcomes were improvement in PANSS subscale scores, discontinuation due to adverse events or inefficacy, and the incidence of 16 adverse events.

RESULTS

We calculated mean difference or risk ratios and 95% credible intervals. We identified 34 RCTs (6798 patients; mean study duration, 9.0 ± 4.24 weeks; proportion of male patients, 53.7%; mean age, 43.3 years). Besides placebo, studies included aripiprazole, asenapine, blonanserin, blonanserin-patch, brexpiprazole, clocapramine (no PANSS data), clozapine (no PANSS data), haloperidol, lurasidone, mosapramine, olanzapine, paliperidone, perospirone, quetiapine, and risperidone. Efficacy and safety profiles differed for antipsychotics used with schizophrenia in Japanese patients. All active treatments other than haloperidol and quetiapine outperformed placebo to improve PANSS-T. Asenapine, olanzapine, paliperidone, and risperidone outperformed placebo for all-cause discontinuation. Asenapine, blonanserin, blonanserin-patch, haloperidol, lurasidone, mosapramine, olanzapine, paliperidone, and risperidone outperformed placebo to improve PANSS positive subscale scores. Aripiprazole, asenapine, blonanserin, blonanserin-patch, brexpiprazole, lurasidone, olanzapine, paliperidone, perospirone, and risperidone outperformed placebo to improve PANSS negative subscale scores. The confidence in evidence of most outcomes was low or very low.

CONCLUSION

Our results are similar to those of previous network meta-analysis involving various races and ethnicities.

Excessive Intake of High-Fructose Corn Syrup Drinks Induces Impaired Glucose Tolerance

The number of patients with diabetes was approximately 463 million worldwide in 2019, with almost 57.6% of this population concentrated in Asia. Asians often develop type 2 diabetes (T2D), even if they are underweight and consume a smaller amount of food. Soft drinks contain large amounts of sweeteners, such as high-fructose corn syrup (HFCS). Excessive intake of HFCS drinks is considered to be one of the causes of T2D. In the present study, we investigated the effect of excessive consumption of HFCS-water on glucose tolerance and obesity under conditions of controlled caloric intake using a mouse model. Three-week-old male ICR mice were divided into two groups and given free access to 10% HFCS-water or deionized water. The caloric intake was adjusted to be the same in both groups using a standard rodent diet. The excess HFCS-water intake did not lead to obesity, but led to impaired glucose tolerance (IGT) due to insulin-secretion defect. It affected glucose and fructose metabolism; for example, it decreased the expression of glucokinases, ketohexokinase, and glucose transporter 2 in the pancreas. These results suggest that excessive consumption of HFCS drinks, such as soft drinks, without a proper diet, induces nonobese IGT due to insulin-secretion defect.

TYK2 Promoter Variant Is Associated with Impaired Insulin Secretion and Lower Insulin Resistance in Japanese Type 2 Diabetes Patients

Accumulating evidence has suggested that viral infection causes type 1 diabetes due to direct β-cell damage and the triggering of autoimmune reactivity to β cells. Here, we elucidated that the tyrosine kinase 2 (Tyk2) gene, encoding an interferon receptor signaling molecule, is responsible for virus-induced diabetes in mice, and its promoter variant confers a risk of type 1 diabetes in humans. This study investigated the relationship between a TYK2 promoter variant (TYK2PV) and insulin secretion in type 2 diabetes patients. TYK2PV status was determined using direct DNA sequencing and its associations with fasting insulin, C-peptide, and homeostatic model assessment of insulin resistance (HOMA-IR) were evaluated in type 2 diabetes patients without sulfonylurea or insulin medication. Of the 172 patients assessed, 18 (10.5%) showed TYK2PV-positivity. Their body mass index (BMI) was significantly lower than in those without the variant (23.4 vs. 25.4 kg/m2, p = 0.025). Fasting insulin (3.9 vs. 6.2 μIU/mL, p = 0.007), C-peptide (1.37 vs. 1.76 ng/mL, p = 0.008), and HOMA-IR (1.39 vs. 2.05, p = 0.006) were lower in those with than in those without the variant. Multivariable analysis identified that TYK2PV was associated with fasting insulin ≤ 5 μIU/mL (odds ratio (OR) 3.63, p = 0.025) and C-peptide ≤ 1.0 ng/mL (OR 3.61, p = 0.028), and also lower insulin resistance (HOMA-IR ≤ 2.5; OR 8.60, p = 0.042). TYK2PV is associated with impaired insulin secretion and low insulin resistance in type 2 diabetes. Type 2 diabetes patients with TYK2PV should be carefully followed in order to receive the appropriate treatment including insulin injections.

Sodium Intake and Incidence of Diabetes Complications in Elderly Patients with Type 2 Diabetes-Analysis of Data from the Japanese Elderly Diabetes Intervention Study (J-EDIT)

This study investigates the associations between sodium intake and diabetes complications in a nationwide cohort of elderly Japanese patients with type 2 diabetes aged 65–85. Data from 912 individuals regarding their dietary intake at baseline is analyzed and assessed by the Food Frequency Questionnaire based on food groups. Primary outcomes are times to diabetic retinopathy, overt nephropathy, cardiovascular disease (CVD), and all-cause mortality during six years. We find that mean sodium intake in quartiles ranges from 2.5 g to 5.9 g/day. After adjustment for confounders, no significant associations are observed between sodium intake quartiles and incidence of diabetes complications and mortality, except for a significant trend for an increased risk of diabetic retinopathy (p = 0.039). Among patients whose vegetable intake was less than the average of 268.7 g, hazard ratios (HRs) for diabetic retinopathy in patients in the second, third, and fourth quartiles of sodium intake compared with the first quartile were 0.87 (95% CI, 0.31–2.41), 2.61 (1.00–6.83), and 3.70 (1.37–10.02), respectively. Findings indicate that high sodium intake under conditions of low vegetable intake is associated with an elevated incidence of diabetic retinopathy in elderly patients with type 2 diabetes.

Current Status and Issues Associated with Bariatric and Metabolic Surgeries in Japan

Among Asian countries, laparotomic and laparoscopic bariatric surgeries were introduced in Japan after its establishment in Taiwan. However, despite high prevalence of potential patients with obesity and diabetes, the wider incorporation of surgery into treatment regimen has been stalling for decades in Japan. While the unique Japanese national health insurance system has guaranteed fair healthcare delivery, it might have worked as a barrier to the development of bariatric and metabolic surgeries (BMS). The present article reviews the status of BMS in Japan and discusses recent issues related to its use. To focus on and identify the major obstacles inhibiting the widespread use of BMS, we have comprehensively covered some major areas including the insurance system, surgical indication, accreditation and training system, original research, and national registry.

Influence of diabetes on short-term outcome after major hepatectomy: an underestimated risk?

BACKGROUND

Patient-related risk factors such as diabetes mellitus and obesity are increasing in western countries. At the same time the indications for liver resection in both benign and malignant diseases have been significantly extended in recent years. Major liver resection is performed more frequently in a patient population of old age, comorbidity and high rates of neoadjuvant chemotherapy. The aim of this study was to evaluate whether diabetes mellitus, obesity and overweight are risk factors for the short-term post-operative outcome after major liver resection.

METHODS

Four hundred seventeen major liver resections (≥ 3 segments) were selected from a prospective database. Exclusion criteria were prior liver resection in patient's history and synchronous major intra-abdominal procedures. Overweight was defined as BMI ≥ 25 kg/m2 and < 30 kg/m2 and obesity as BMI ≥ 30 kg/m2. Primary end point was 90-day mortality and logistic regression was used for multivariate analysis. Secondary end points included morbidity, complications according to Clavien-Dindo classification, unplanned readmission, bile leakage, and liver failure. Morbidity was defined as occurrence of a post-operative complication during hospital stay or within 90 days postoperatively.

RESULTS

Fifty-nine patients had diabetes mellitus (14.1%), 48 were obese (11.6%) and 147 were overweight (35.5%). There were no statistically significant differences in mortality rates between the groups. In the multivariate analysis, diabetes was an independent predictor of morbidity (OR = 2.44, p = 0.02), Clavien-Dindo grade IV complications (OR = 3.6, p = 0.004), unplanned readmission (OR = 2.44, p = 0.04) and bile leakage (OR = 2.06, p = 0.046). Obese and overweight patients did not have an impaired post-operative outcome compared patients with normal weight.

CONCLUSIONS

Diabetes has direct influence on the short-term postoperative outcome with an increased risk of morbidity but not mortality. Preoperative identification of high-risk patients will potentially decrease complication rates and allow for individual patient counseling as part of a shared decision-making process. For obese and overweight patients, major liver resection is a safe procedure.

Fixed-ratio combination of basal insulin and glucagon-like peptide-1 receptor agonists in the treatment of Japanese people with type 2 diabetes: An innovative solution to a complex therapeutic challenge

Over 10 million people in Japan have known or suspected type 2 diabetes (T2D), and this number is expected to rise. Although many people require therapy escalation because of the progressive nature of T2D, this appears to be suboptimal in Japanese real-world clinical practice. Insulin therapy tends to be introduced only when glycaemic control is very poor (mean glycated haemoglobin >9%). Although basal insulin therapy is effective in reducing fasting plasma glucose (FPG), postprandial plasma glucose often remains uncontrolled. Basal-bolus insulin regimens are complex and carry the risk of weight gain and hypoglycaemia. Recently, fixed-ratio combinations (FRCs) of BI and glucagon-like peptide-1 receptor agonists (GLP-1RAs) have shown efficacy in reducing both FPG and postprandial plasma glucose with a single injection and without increased risk of hypoglycaemia or weight gain. IDegLira, a titratable FRC of insulin degludec (100 U/mL) and liraglutide, is currently available in Japan and the United States/European Union at a ratio of 1 U (unit):0.036 mg. iGlarLixi (insulin glargine 100 U/mL and lixisenatide at a ratio of 1:1 (20 U/20 μg) has recently been approved in Japan. Phase 3 trials in Japan for IDegLira (DUAL Japan) and iGlarLixi (LixiLan JP) have shown that both FRCs are efficacious. This review provides an overview of IDegLira and iGlarLixi (Japanese formulation) and considers their potential use as new therapeutic options to address the clinical need for early glycaemic control in Japanese people with T2D.

Family Support for Medical Nutritional Therapy and Dietary Intake among Japanese with Type 2 Diabetes (JDDM 56)

The aim of this study was to investigate the association between habitual dietary intake for patients with diabetes and the content of family support for medical nutritional therapy (MNT). Analyzed were 289 Japanese with type 2 diabetes (men, 58.5%; mean age, 62.0 years; mean HbA1c, 53.4 mmol/mol) who completed the Food Frequency Questionnaire and Diabetes Family Behavior Checklist (DFBC). Relationships of mean values for food group intake to DFBC responses regarding MNT were examined using multivariate analysis of covariance. Positive response to "Praise for following diet" was associated with lower sweets intake (none: 60.1 g/day; ≥once monthly: 50.9 g/day, p = 0.038) and higher seasoning intake (none: 21.6 g/day, ≥once monthly: 24.1 g/day, p = 0.046). Energy intake was higher with positive responses to "Eat at the same time that you do" (none: 1636 kcal/day, ≥once monthly: 1818 kcal/day, p = 0.038). "Nags about not following diet" was associated with higher fish (none: 68.7 g/day, ≥once monthly: 78.7 g/day, p = 0.042) and salt intake (none: 8.3 g/day, ≥once monthly: 9.0 g/day, p = 0.014). Eating foods not part of the diabetic diet (none: 218.4 g/day, ≥once monthly: 246.9 g/day, p = 0.014) resulted in a higher vegetable intake. In females, significant differences in relationships in the overall analysis were reversed. Our results clarified relationships between types of family support of patients with type 2 diabetes and their dietary intake and the importance of sex differences for more effective MNT.

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.

Liver fat accumulation assessed by computed tomography is an independent risk factor for diabetes mellitus in a population-based study: SESSA (Shiga Epidemiological Study of Subclinical Atherosclerosis)

AIMS

Ectopic fat accumulation is related to insulin resistance and diabetes mellitus (DM). However, the effect of fatty liver on DM in non-obese individuals has not been clarified. We investigated whether liver fat accumulation assessed by computed tomography (CT) is associated with the incidence of DM.

METHODS

In a prospective population-based study, 640 Japanese men were followed up for 5 years. The liver to spleen (L/S) ratio of the CT attenuation value was used as the liver fat accumulation index. We calculated the odds ratio (OR) and 95% confidence interval (CI) for the DM incidence of per 1 standard deviation (SD) lower L/S and those of L/S < 1.0 compared with L/S ≥ 1.0, using logistic regression models.

RESULTS

Both per 1 SD lower L/S and L/S < 1.0 were significantly associated with a risk for DM incidence (1 SD lower L/S: OR = 1.57, 95%CI = 1.14-2.16; L/S < 1.0: OR = 2.27, 95%CI = 1.00-5.14). The relationship between L/S and incidence of DM was consistent in the obese and non-obese groups, with thresholds of BMI 25 kg/m², waist circumference 85 cm, or visceral adipose tissue 100 cm².

CONCLUSIONS

Liver fat accumulation assessed by CT was associated with the incidence of DM.

Changing the Concept of Type 2 Diabetes: Beta Cell Workload Hypothesis Revisited

BACKGROUND

Despite a number of innovations in anti-diabetic drugs and substantial improvement in diabetes care, the number of people with diabetes continues to increase, suggesting further need to explore novel approaches to prevent diabetes. Type 2 diabetes (T2DM) is characterized by beta cell dysfunction and insulin resistance. However, insulin resistance, usually a consequence of obesity, is often emphasized and the role of beta cell dysfunction in T2DM is less appreciated.

OBJECTIVE AND RESULTS

This paper summarizes recent evidence showing the importance of beta cell dysfunction in T2DM and refines the "beta cell workload hypothesis", emphasizing the importance of beta cell preservation for the prevention and management of T2DM.

CONCLUSION

It is hoped that this novel concept will foster a better understanding of the pathophysiology of T2DM by not only medical staff and patients with diabetes, but also the general population, and encourage more people to adhere to a healthy lifestyle, eventually resulting in "stopping diabetes".

Vitamin B6 intake and incidence of diabetic retinopathy in Japanese patients with type 2 diabetes: analysis of data from the Japan Diabetes Complications Study (JDCS)

PURPOSE

Although vitamin B6 has been suspected to prevent the progression of diabetic retinopathy, evidence of this in patients with type 2 diabetes based on longitudinal studies is sparse. This study investigated the relationship between vitamin B6 intake and the incidence of diabetic retinopathy in Japanese patients with type 2 diabetes.

METHODS

The study was part of an examination of a nationwide cohort of patients with type 2 diabetes aged 40-70 years with HbA1c ≥ 48 mmol/mol. After excluding nonresponders to a dietary survey using the Food Frequency Questionnaire based on food groups, 978 patients were analyzed. Primary outcome was the 8-year risk of a diabetic retinopathy event, and Cox regression analyses estimated hazard ratios (HRs) for retinopathy according to vitamin B6 intake adjusted for age, gender, body mass index, HbA1c, smoking, energy intake, and other confounders.

RESULTS

Mean vitamin B6 intake in quartiles ranged from 1.1 to 1.6 mg/day, and half of the participants had vitamin B6 intake below the recommended daily dietary allowance according to dietary reference intakes in Japanese adults (men 1.4 mg/day; women 1.2 mg/day). After adjusting for confounders, HRs for diabetic retinopathy in the 2nd, 3rd, and 4th quartile groups of vitamin B6 intake compared with the 1st quartile group were 1.17 (95% confidence interval 0.81-1.69, p = 0.403), 0.88 (0.58-1.34, p = 0.550), and 0.50 (0.30-0.85, p = 0.010), respectively.

CONCLUSIONS

Findings suggested that high vitamin B6 intake was associated with a lower incidence of diabetic retinopathy in Japanese with type 2 diabetes.

Effect of switching from pioglitazone to the sodium glucose co-transporter-2 inhibitor dapagliflozin on body weight and metabolism-related factors in patients with type 2 diabetes mellitus: An open-label, prospective, randomized, parallel-group comparison trial

The effects of dapagliflozin (DAP) and pioglitazone (PIO) on body weight and glycaemic control were compared in patients with type 2 diabetes mellitus. Seventy-one patients on PIO were either switched to DAP (n = 36) at 5 mg per day or continued on PIO (n = 35). Primary endpoints were superiority of body weight loss and non-inferiority of HbA1c level after 24 weeks with DAP. Body weight decrease was greater with DAP than with PIO (75.3 ± 14.9 to 71.3 ± 15.1 kg vs. 74.7 ± 13.8 to 75.2 ± 13.9 kg; P < 0.01). Change in the HbA1c level was comparable (P = 0.64). The level of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and urinary albumin : creatinine ratio (ACR) decreased only with DAP (NT-proBNP, P < 0.01; ACR, P = 0.02), and the change in NT-proBNP correlated negatively with baseline NT-proBNP level (ρ = -0.68, P < 0.01) and log-converted ACR (ρ = -0.35, P < 0.05). DAP promotes body weight loss in type 2 diabetes mellitus and may decrease fluid retention, thus reducing the occurrence of cardiovascular events.

Should sulfonylurea be discontinued or maintained at the lowest dose when starting ipragliflozin? A multicenter observational study in Japanese patients with type 2 diabetes

AIMS/INTRODUCTION

We investigated the difference in efficacy and safety between discontinuation and maintaining of sulfonylurea when adding a sodium-glucose cotransporter 2 inhibitor.

MATERIALS AND METHODS

In the present multicenter, prospective observational study, 200 patients with type 2 diabetes treated with sulfonylurea and with a need to add ipragliflozin were enrolled and divided into two groups: discontinued sulfonylurea (Discontinuation group) or maintained sulfonylurea, but at the lowest dose (Low-dose group) when adding ipragliflozin. We compared the two groups after 24 weeks using propensity score matching to adjust for differences between the groups.

RESULTS

In the matched cohort (58 patients in each group), baseline characteristics of both groups were balanced. The primary outcome of the proportion of patients with non-exacerbation in glycated hemoglobin after 24 weeks was 91.4% in the Low-dose group and 75.9% in the Discontinuation group, a significant difference (P = 0.024). However, bodyweight was significantly decreased in the Discontinuation group compared with the Low-dose group (-4.4 ± 2.1 kg vs -2.9 ± 1.9 kg, P < 0.01). Similarly, liver enzyme improvement was more predominant in the Discontinuation group. A logistic regression analysis showed that high-density lipoprotein cholesterol, age and sulfonylurea dose were independent factors associated with non-exacerbation of glycated hemoglobin in the Discontinuation group.

CONCLUSIONS

The purpose of using ipragliflozin should be considered when making the decision to discontinue or maintain sulfonylurea at the lowest dose. Furthermore, low high-density lipoprotein cholesterol level, low dose of sulfonylurea and younger age were possible markers to not show worsening of glycemic control by discontinuing sulfonylurea.

Relationship between body fat and diabetic retinopathy in patients with type 2 diabetes: a nationwide survey in Korea

PURPOSE

To evaluate the association of body mass index (BMI), waist circumference, and body fat with diabetic retinopathy (DR) in Korean patients with type 2 diabetes.

METHODS

Among the 1130 participants 19 years of age or older with type 2 diabetes enrolled in the nationwide survey, a total of 887 participants were included in the analyses after excluding patients with ungradable fundus images. The presence and severity of DR were graded with seven-field fundus photographs. The associations between DR and anthropometric parameters and total body fat, which was assessed by dual-energy X-ray absorptiometry, were analysed using multivariate logistic regression models.

RESULTS

Patients were divided into three groups according to severity of DR: no DR (n = 702, 79.1%), mild/moderate DR (n = 130, 14.7%), and vision-threatening DR (n = 55, 6.2%). In multivariate-adjusted analyses, higher BMI (adjusted odds ratio [aOR], 0.80; 95% confidence interval [CI], 0.70-0.92; P = 0.001), larger waist circumference (aOR, 0.96; 95% CI, 0.91-1.00; P = 0.047), and higher total body fat (aOR, 0.86; 95% CI, 0.79-0.92; P < 0.001) were significantly associated with a lower risk of vision-threatening DR. In sex-stratified analyses, however, only total body fat in women showed a significant inverse association with the presence of DR (aOR, 0.93; 95% CI, 0.88-0.98; P < 0.001) and independently with the severity of DR (P for trend = 0.004).

CONCLUSION

In Korean patients with type 2 diabetes, obese patients might be less likely to have vision-threatening DR. Total body fat in women appears to be inversely and independently associated with DR prevalence and progression.

Elevated blood apelin levels in type 2 diabetes mellitus: A systematic review and meta-analysis

AIMS

Apelin is a circulatory blood peptide acting as a ligand for the orphan G protein-coupled receptor known as APJ. Whether apelin blood levels can affect the pathogenesis of type 2 diabetes mellitus is an open question. In the present study, we aimed to assess the levels of circulatory apelin peptide in the type 2 diabetic subjects using systematic review and meta-analysis under random-effects model and standardized mean difference (SMD) as the effect size. For heterogeneity testing, Q and I²% statistic indices as well as meta-regression were applied.

METHODS

Using specialized biomedical online databases of Pubmed, Pubmed Central, Medline, Google scholar, Scopus and Embase databases without the beginning date restriction until July 2018, the systematic review retrieved nine studies for meta-analysis after fulfilling the inclusion and exclusion criteria.

RESULTS

Analysis of Q and I²% statistic indices as well as meta-regression showed a high heterogeneity in the 16 selected studies (737.578 and 96.475, respectively), thus, the random-effects model was chosen. The primary analysis for the main hypothesis on a total number of 1102 cases and 1078 healthy control subjects found that the weighted pooled SMD for the impact of apelin blood concentration in type 2 diabetes mellitus was as follows: SMD = 2.136 (95% confidence interval, 1.580-2.693). The P-value for the significance of the combined SMD examined by the z-test was 0.000 and thus, it was clearly significant.

CONCLUSIONS

This meta-analysis presents evidence that apelin circulatory levels are higher in type 2 diabetic subjects than normal controls.

Insights into pathogenesis of five novel GCK mutations identified in Chinese MODY patients

OBJECTIVE

Heterozygous inactivating mutations in GCK are associated with defects in pancreatic insulin secretion and/or hepatic glycogen synthesis leading to mild chronic hyperglycaemia of maturity onset diabetes of young type 2 (MODY2). However, the effect of naturally occurring GCK mutations on the pathogenesis for MODY2 hyperglycaemia remains largely unclear, especially in the Asian population. The aim of this study is to explore the potential pathogenicity of novel GCK mutations related to MODY2.

METHODS

Genetic screening for GCK mutations from 96 classical MODY families was performed, and structure-function characterization and clinical profile of identified GCK mutations were conducted.

RESULTS

Five novel (F195S, I211T, V222D, E236G and K458R) and five known (T49N, I159V, R186X, A188T and M381T) mutations were identified and co-segregated with hyperglycaemia in their pedigrees. R186X generates non-functional truncated form and V222D and E236G fully inactivate glucokinase due to severe structure disruptions. The other seven GCK mutations exhibited marked reductions in catalytic efficiency and thermo-stability; notably, the interaction with GKRP was significantly enhanced in I211T, I159V, T49N and K458R, reduced in F195S and M381T, and completely lost with A188T. 31% (17/55) of MODY2 patients showed signs of insulin resistance. Conventional hypoglycaemia treatment did not improve the HbA1C in MODY2 patients when insulin resistance is not present.

CONCLUSIONS

Five novel GCK mutations have been identified in Chinese MODY. The defects in enzymatic activity and protein stability, together with alteration of GKRP binding on GCK mutants may synergistically contribute to the development of MODY2 hyperglycaemia. No treatment should be prescribed to MODY2 patients when insulin resistance is not present.

Cross-sectional study of the association between day-to-day home blood pressure variability and visceral fat area measured using the dual impedance method

Background

The blood pressure (BP) variability (BPV) is a predictor of cardiovascular disease, independently of the BP itself. In addition, visceral fat accumulation can trigger atherosclerotic disease through various mechanisms.

Methods and results

We examined the association between fat accumulation and day-to-day BPV in 61 adult hypertensive patients. Visceral fat area (VFA) was measured using the dual bioelectrical impedance analysis method. Participants were divided into three groups based on VFA. The standard deviation (SD) in home systolic BP (SBP) for 7 consecutive days was significantly lower in the high VFA tertile (low VFA, 8.40±4.15 mmHg; intermediate VFA, 8.47±2.80 mmHg; and high VFA, 5.84±2.37 mmHg, p of One-way ANOVA = 0.017, p for trend = 0.0126). A similar association was observed between the coefficient of variance (CV) of home SBP and the VFA tertile. Multiple-regression analysis adjusted for age, sex, antihypertensive drug, diabetes, habitual drinking, and SBP level also showed a significant association between the VFA tertile and the SD or CV of home SBP. The adjusted coefficient of regression for the SD of home SBP was -3.28 (95%CI: -5.60 to -0.97, p = 0.008) and the CV of home SBP was -2.51 (95%CI: -4.31 to -0.71, p = 0.008) for the highest VFA tertile as compared to the lowest VFA tertile.

Conclusions

These results show for the first time negative correlation between VFA and day-to-day BPV. The degree of obesity should be taken into account when evaluating the value of BPV.

Influence of food texture on energy metabolism and adiposity in male rats

NEW FINDINGS

What is the central question of this manuscript? What is the effect of food texture on fat accumulation, lipogenesis and proinflammatory factors in the adipose tissue and on energy balance in male rats? What is the main finding and its importance? Calorie intake and fat accumulation in rats fed soft pellets ad libitum increased, but their body weight did not. The data suggest that, even when BMI is normal, frequent consumption of soft food may contribute to the development of lifestyle-related diseases.

ABSTRACT

Dietary factors such as food texture are known to affect feeding behaviour and energy metabolism. We recently found that rats fed soft pellets (SPs) on a 3 h restricted feeding schedule showed glucose intolerance, insulin resistance with disruption of insulin signalling, and hyperplasia of pancreatic β-cells, even though there were no differences in energy intake and body weight between rats fed control pellets (CPs) and rats fed SPs. We investigated the effect of food texture on fat accumulation, lipogenesis and proinflammatory factors in the mesenteric fat, as well as on energy balance in male rats fed CPs or SPs. We used 7-week-old Wistar rats that were randomly divided into two groups, ad libitum fed either CPs or SPs for 27 weeks. Body weight and calorie intake were monitored once a week throughout the experiment. The calorie intake, lipogenesis and fat accumulation of the rats fed SPs increased, whereas their body weight did not. Additionally, SP rats used their fat mainly as a source of energy and increased their energy expenditure. Our data suggest that the habit of frequently eating soft food causes visceral fat accumulation without an increase in body weight. Further investigations using soft-textured foods could lead to the development of appropriate interventions for non-overweight patients with lifestyle-related diseases.

Body mass index ≥23 is a risk factor for insulin resistance and diabetes in Japanese people: A brief report

Background

Screening for undiagnosed type 2 diabetes mellitus is recommended for Asian Americans with a body mass index ≥23. However, the optimal body mass index cut-off score for predicting the risk of diabetes mellitus in Japanese people is not well known. The aim of this study was to determine the best body mass index cut-off score for predicting insulin resistance and diabetes mellitus in the Japanese population.

Methods

This study had two parts, a clinical investigation and a retrospective observational investigation. In the clinical part of the study, 58 participants (26 with type 2 diabetes mellitus and 32 non-diabetics) underwent a hyperinsulinemic-euglycemic clamp from which their glucose disposal rate was measured. For the retrospective part of the study, medical check-up data from 88,305 people in the Tottori Prefecture were analyzed for clinical evidence of diabetes mellitus. The optimal BMI cut-off scores for prediction of insulin resistance and diabetes mellitus were determined.

Results

In the clamp study, the optimal body mass index cut-off score to predict insulin resistance in non-diabetic patients was 22.7. All participants with type 2 diabetes mellitus were insulin resistant, and the optimal body mass index cut-off score for prediction of severe insulin resistance was 26.2. When the data from the type 2 diabetic and the non-diabetic participants were combined, the optimal body mass index cut-off score for prediction of insulin resistance was 23.5. Analysis of 88,305 medical check-up records yielded an optimal body mass index cut-off score for prediction of diabetes mellitus of 23.6.

Conclusions

These results suggest that having a body mass index ≥23 is a risk factor for insulin resistance and diabetes mellitus in the Japanese population.

Twelve-year trends of increasing overweight and obesity in patients with diabetes: the Shiga Diabetes Clinical Survey

The prevalence of obesity is increasing globally in patients with diabetes. This study aimed to examine 12-year trends of increasing obesity in Japanese patients with diabetes, and their clinical features. The study used results of the Shiga Diabetes Clinical Survey, which recorded medical performance in diabetic patients in 2000, 2006 and 2012. Data were analyzed from 14,205, 14,407 and 21,449 adult patients in these three years, respectively. Overweight and obesity prevalence and the clinical features of diabetes patients were examined, stratified by body mass index (BMI) and age. The prevalence of overweight (BMI 25-30 kg/m²) and obesity (BMI ≥30 kg/m²) were 27.0% and 5.1% in 2000, 28.9% and 7.3% in 2006 and 30.9% and 10.0% in 2012. Glycemic control, blood pressure and serum lipid profile improved over 12 years in all BMI categories. However, glycemic and triglyceride control were insufficient in obese patients aged <65 years (hemoglobin A1c 7.5 ± 1.4%, triglyceride 197.7 ± 178.4 mg/dL in 2012). The percentage of patients who used antihypertensive and lipid-lowering drugs increased and patients with higher BMI had increased frequency of using these drugs, both in young and old age groups. Higher BMI was significantly and positively associated with albuminuria. In summary, overweight and obesity have increased in Japanese diabetic patients, particularly for younger generations. Findings suggest that obesity may lead to poorer glycemic control, blood pressure and lipid profiles. Overweight and obesity are important modifiable risk factors for diabetes, suggesting that more active weight-control interventions are warranted.

Canagliflozin for the treatment of type 2 diabetes: a comparison between Japanese and non-Japanese patients

INTRODUCTION

Canagliflozin, a sodium-glucose co-transporter-2 (SGLT2) inhibitor, improves various cardiometabolic parameters. Although canagliflozin was originally discovered in Japan, no comprehensive summary of its effects in Japanese patients has been reported. As differences exist in the pathologic features of diabetes between Japanese and non-Japanese populations, it is important to consolidate Japanese data for canagliflozin. Areas covered: The authors summarize Japanese clinical trial and post-marketing surveillance data for canagliflozin, and make comparisons with non-Japanese data. They also consider the therapeutic potential of canagliflozin in Japanese patients by presenting results from the CANagliflozin cardioVascular Assessment Study (CANVAS) Program. Expert opinion: In Japanese patients, canagliflozin 100 mg, administered as monotherapy or combination therapy, improved blood glucose, body weight, and blood pressure, and was well tolerated; the efficacy and safety profiles were comparable to previous clinical studies in other countries. In the CANVAS Program, canagliflozin reduced major cardiovascular events, and although Japan was not included in this program, canagliflozin may have cardiovascular benefits in Japanese patients, in whom control of multiple risk factors is important for preventing diabetic complications. Patients with high cardiovascular risk often have multiple comorbidities, so it is important to consider the risk-benefit balance of using SGLT2 inhibitors in individual patients.

Meat intake and incidence of cardiovascular disease in Japanese patients with type 2 diabetes: analysis of the Japan Diabetes Complications Study (JDCS)

PURPOSE

Excessive meat intake has been researched as a major cause of cardiovascular disease (CVD) among healthy adults, but data on this topic in Asian patients with diabetes are sparse. The quantity and variety of available meats vary widely between Asian and Western countries. As part of a nationwide cohort study we investigated the relationship between meat intake and incidence of CVD in Japanese patients with type 2 diabetes aged 40-70 years with HbA1c ≥ 6.5%.

METHODS

Analyzed were 1353 responders to a baseline dietary survey assessed by the Food Frequency Questionnaire based on food groups. Primary outcome was the 8-year risk of a CVD event, including coronary heart disease (CHD) and stroke. Cox regression analyses estimated hazard ratios (HRs) for dietary intake adjusted for age, gender, body mass index, HbA1c, smoking, energy intake, and other confounders.

RESULTS

Mean meat intake in quartiles ranged from 9.9 to 97.7 g/day. After adjusting for confounders, HRs of CHD in the 2nd, 3rd, and 4th quartiles for meat intake compared with the 1st quartile were 2.84 (95% confidence interval 1.29-6.24, p = 0.01), 3.02 (1.36-6.70, p < 0.01), and 2.99 (1.35-6.65, p = 0.01), respectively. In two groups according to meat intake, patients consuming ≥ 20 g/day of meat had a 2.94-fold higher risk of CHD than those consuming < 20 g/day (p < 0.01). There was no significant association of stroke with meat intake.

CONCLUSIONS

An elevated incidence of CHD in Japanese patients with type 2 diabetes was associated with high meat intake.

Lower-limb muscle strength according to bodyweight and muscle mass among middle age patients with type 2 diabetes without diabetic neuropathy

[Purpose] This study assessed the effects of type 2 diabetes without diabetic polyneuropathy on muscle strength according to body composition in middle age patients. [Subjects and Methods] This study included 45 non-diabetic individuals (control group) and 50 patients with type 2 diabetes (DM group), 40 to 64 years of age. The body composition was examined, including the leg muscle volume (LMV), which was the sum of the lower-limb muscle mass. The muscle strength was also examined, and the knee extension force (KEF), ankle dorsiflexion force (ADF). The KEF and ADF were normalized to the bodyweight, and the total leg muscle force (TLMF) were calculated by combining the KEF and ADF. The leg muscle quality (LMQ) was calculated as the TLMF normalized with the LMV. [Results] While no significant differences were found in the LMV between groups, the body mass index were higher in the DM group than in the control group. Significant differences were observed in %KEF, %ADF, and the LMQ in the DM group, with 15.8%, 18.7%, and 11.5% lower values than those in the control group, respectively. [Conclusion] The results of this study may demonstrate that muscle weakness occurs before diabetes progresses to a severe condition.

Efficacy and safety of ipragliflozin and metformin for visceral fat reduction in patients with type 2 diabetes receiving treatment with dipeptidyl peptidase-4 inhibitors in Japan: a study protocol for a prospective, multicentre, blinded-endpoint phase IV randomised controlled trial (PRIME-V study)

INTRODUCTION

In Japan, dipeptidyl peptidase-4 (DPP-4) inhibitors are frequently used as the treatment of choice for patients with type 2 diabetes. In some cases, however, poor glycaemic and body weight control issues persist despite treatment with DPP-4 inhibitors. Previous researchers have revealed that sodium-dependent glucose transporter-2 (SGLT-2) inhibitors reduce both plasma glucose levels and body weight in patients with type 2 diabetes. However, further investigation regarding the effects of SGLT-2 inhibitors on body composition, especially in the Asian population who tends to have relatively low-to-moderate body mass indices, is required. Therefore, we aim to determine the effects of treatment with SGLT-2 inhibitors or metformin for reducing visceral fat in 106 Asian patients with type 2 diabetes who were undergoing treatment with the DPP-4 inhibitor sitagliptin (50 mg daily) for poor glycaemic control.

METHODS AND ANALYSIS

A prospective, multicentre, blinded-endpoint phase IV randomised controlled study will be conducted to evaluate the safety and efficacy of a 24-week treatment with either an SGLT-2 inhibitor (ipragliflozin) or metformin for reducing visceral fat and plasma glucose levels in patients with type 2 diabetes. Patients who satisfy the eligibility criteria will be randomised (1:1) to receive ipragliflozin (50 mg daily) or metformin (1000 mg daily). The primary outcome is the rate of change in the total area of visceral fat for patients in both treatment groups, measured using CT, after 24 weeks of therapy. Two radiologists, blinded to the clinical information, will perform centralised analysis of the images in a unified measurement condition.

ETHICS AND DISSEMINATION

The protocol was approved by the institutional review board of each hospital. This study is ongoing and due to finish in April 2017. The findings of this study will be disseminated via peer-reviewed publications and conference presentations, and will also be disseminated to participants.

TRIAL REGISTRATION NUMBER

UMIN000015170, R000016861 (https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000016861); Pre-results.

Dietary salt intake and diabetes complications in patients with diabetes: An overview

Dietary salt restriction is an essential constituent of diabetes care in preventing or slowing the development of diabetes complications, and many diabetes management guidelines include recommendations for dietary salt intake. However, descriptions of guidelines for salt intake are sometimes confined to studies of participants without diabetes or small short-term studies of patients with diabetes. However, in response to such situations, recent longitudinal studies of patients with diabetes have reported an association between dietary salt intake and diabetes complications. Thus, this review summarizes important points in the current situation regarding guidelines on salt intake and the latest findings and future issues on dietary salt intake for diabetes care focusing on (i) the current status and issues regarding the leading guidelines for dietary salt intake for diabetes care in various regions worldwide, and (ii) findings on salt intake from recent longitudinal studies of patients with diabetes whose dietary salt intake was restricted.

Is the Proportion of Carbohydrate Intake Associated with the Incidence of Diabetes Complications?-An Analysis of the Japan Diabetes Complications Study

The appropriate proportions of macronutritional intake have been controversial in medical nutritional therapy for diabetes, and evidence of the effects of carbohydrate consumption on diabetes complications in prospective settings is sparse. We investigated the relationships between proportions of carbohydrate intake as the % of total energy and diabetes complications in a nationwide cohort of Japanese patients with type 2 diabetes aged 40–70 years with hemoglobin A1c ≥6.5%. The analysis was of 1516 responders to a baseline dietary survey assessed by the Food Frequency Questionnaire based on food groups. Primary outcomes were times to overt nephropathy, diabetic retinopathy, and cardiovascular disease (CVD) after 8 years. Hazard ratios (HRs) for proportions of carbohydrate intake were estimated by Cox regression adjusted for confounders. High carbohydrate intake was significantly related to higher intakes of grain, fruits, and sweets/snacks and lower intakes of soybean and soy products, vegetables, seaweed, meat and processed meat, fish and processed fish, eggs, milk and dairy products, oil, and alcoholic beverages. During the eight-year follow-up, there were 81, 275, and 129 events of overt nephropathy, diabetic retinopathy, and CVD, respectively. After adjustment for confounders, HRs for complications in patients with carbohydrate intake in the second or third tertiles (51.0%–56.4% and ≥56.5%, respectively) compared with carbohydrate intake in the first tertile (<50.9%, referent) were analyzed. No significant associations were shown in the second and third tertiles relative to first tertile (overt nephropathy: 1.05 (95% Confidence Interval, 0.54–2.06) and 0.98 (0.40–2.44); diabetic retinopathy: 1.30 (0.90–1.88) and 1.30 (0.78–2.15); and CVD: 0.95 (0.55–1.63) and 1.37 (0.69–2.72)). By exploring potentially nonlinear relationships, trends for the incidence of diabetes complications according to proportions of carbohydrate intake were not clearly shown. Findings suggested that proportions of carbohydrate intake were not associated with the incidence of diabetes complications among type 2 diabetes patients in Japan.