Optimal waist circumference cut-off points and ability of different metabolic syndrome criteria for predicting diabetes in Japanese men and women: Japan Epidemiology Collaboration on Occupational Health Study

Comparison of waist circumference and waist-to-height ratio as predictors of clustering of cardiovascular risk factors among middle-aged people in rural Khanh Hoa, Vietnam

OBJECTIVE

Given the population-level variation in stature, a universal cut-off for waist circumference (WC) may not be appropriate for some populations. We compared the performance of WC and waist-to-height ratio (WHtR) to detect the clustering of cardiovascular disease (CVD) risk factors in rural Vietnam.

METHODS

We obtained data from a baseline survey of the Khanh Hoa Cardiovascular Study comprising 2942 middle-aged residents (40-60 years). We used areas under the receiver operating characteristics curve (AUROC), net reclassification index (NRI), and integrated discrimination improvement (IDI) to compare the performance of WC and WHtR in predicting CVD risk clustering (≥2 of the following risk factors: hypertension, diabetes, dyslipidemia, and elevated C-reactive protein).

RESULTS

The optimal cut-off values for WC were 81.8 and 80.7 cm for men and women, respectively. Regarding the clustering of CVD risk factors, the AUROC (95% CI) of WC and WHtR were 0.707 (0.676 to 0.739) and 0.719 (0.689 to 0.749) in men, and 0.682 (0.654 to 0.709) and 0.690 (0.663 to 0.717) in women, respectively. Compared with WC, WHtR had a better NRI (0.229; 0.102-0.344) and IDI (0.012; 0.004-0.020) in men and a better NRI (0.154; 0.050-0.257) in women.

CONCLUSIONS

The optimal WC cut-off for Vietnamese men was approximately 10 cm below the recommended Asian cut-off. WHtR might perform slightly better in predicting the clustering of CVD risk factors among the rural population in Vietnam.

Relationship of normal-weight central obesity with the risk for heart failure and atrial fibrillation: analysis of a nationwide health check-up and claims database

Aims

There have been scarce data on the relationship of normal-weight central obesity (NWCO) with the subsequent risk for heart failure (HF) and atrial fibrillation (AF). Using a nationwide health check-up and administrative claims database, we sought to clarify whether NWCO would be associated with the incidence of HF and AF.

Methods and results

Medical records of 1 697 903 participants without prior history of cardiovascular disease (CVD) and normal-weight (body mass index of 18.5–23.0 kg/m²) were extracted from the JMDC Claims Database, which is a health check-up and claims database. We defined NWCO as normal-weight and CO (waist circumference ≥ 90 cm for men or ≥ 80 cm for women). The median age was 44.0 (37.0–52.0) years and 872 578 (51.4%) participants were men. Overall, 154 778 individuals (9.1%) had CO. The mean follow-up period was 3.3 ± 2.6 years. Participants with NWCO were older and more likely to be women than those without. HF and AF occurred in 26 936 (1.6%) and 6554 (0.4%) participants, respectively. People having NWCO were associated with a greater risk for HF [hazard ratio (HR): 1.072, 95% confidence interval (CI) 1.026–1.119] and AF (HR: 1.202, 95% CI: 1.083–1.333) compared with those having normal-weight without CO.

Conclusion

Our analysis of a nationwide health check-up and administrative claims database including ∼1.7 million participants without prevalent CVD history demonstrated the potential impact of NWCO on the risk for HF and AF, suggesting the importance of abdominal obesity in the developing HF and AF even in normal-weight individuals.

Prevalence of Locomotive Dysfunction Exacerbating Systolic Blood Pressure and Abdominal Circumference: A Longitudinal Cohort Analysis

Background: We aimed to investigate the influence of locomotive dysfunction (LD) on the future prevalence of metabolic syndrome (MetS) in community-dwelling people using propensity score matching (PSM). Materials and Methods: Two hundred and twenty-five volunteers (87 men and 138 women, mean age: 66.9 years) underwent a health screening program in 2012 and 2014. We extracted 92 volunteers with LD and 133 without LD in 2012. After performing 1:1 PSM using clinical variables, including age, sex, individual MetS components, and comorbidities between the two groups, we investigated the prevalence of MetS between the two groups (LD and non-LD) in 2014. Results: Seventy-three subjects were enrolled in each group. In 2012, the mean the 25-question Geriatric Locomotive Function Scale was 2.6 in the non-LD group and 13.4 in the LD group. The baseline prevalence of MetS was 9 (12.3%) in non-LD group and 8 (11%) in LD group. After 2 years, the prevalence of MetS in the LD group increased to 18 (24.7%), but only by 8 (11%) (P = 0.031) in the non-LD group. Among MetS components, waist circumference (84.9 vs. 82.5 cm) and systolic blood pressure (SBP) (145 vs. 140 mmHg) in the LD group were significantly higher than in the non-LD group (P = 0.047, P = 0.023). Conclusions: The longitudinal analysis showed that LD increases the prevalence of MetS and deteriorates SBP and abdominal circumference over 2 years.

Comparison of Body Mass Index and Waist Circumference in the Prediction of Diabetes: A Retrospective Longitudinal Study

INTRODUCTION

Both body mass index (BMI) and waist circumference (WC) are associated with diabetes risk, and the difference between them in predictive ability for diabetes is still contentious. We conducted a population-based study to investigate and compare the association of them with diabetes by sex.

METHODS

This study included a total of 4754 subjects aged 40-80 years with no diabetes at baseline between 2008 and 2017. Using multivariate Cox proportional hazards models, we calculated hazard ratios for diabetes according to tertiles of BMI or WC. Harrell's C statistics was applied to assess and compare the predictive ability of the models using BMI and WC.

RESULTS

Both BMI and WC showed the significant positive trends with diabetes risk. In men, the extreme tertiles (BMI > 25.1 kg/m² and WC > 88.0 cm) provided 1.58-fold or 2.04-fold higher risk compared with the first tertiles (< 22.6 kg/m² and < 81.2 cm). In women, BMI > 24.4 kg/m² showed 3.28-fold higher risk than the first tertile (< 21.6 kg/m²), whereas WC ≥ 78.2 cm was more than twice as likely to suffer from diabetes as WC < 78.2 cm. BMI and WC showed a comparative performance in predicting diabetes in both sexes (P value 0.447 in men, and 0.337 in women).

CONCLUSION

Both BMI and WC showed a positive association with diabetes and offered a comparative predictive performance for diabetes in both sexes. The cut-off points, BMI 25.1 kg/m² and WC 88.0 cm in men and BMI 24.4 kg/m² and WC 78.2 cm in women, might contribute to the effective prevention strategies for diabetes.

Relationship between anthropometric characteristics and aerobic fitness among Malaysian men and women

This cross-sectional study evaluated the relationships between anthropometric and aerobic fitness (rate of perceived exertion [RPE] and predicted maximal oxygen uptake [VO_2max]) among 228 participants (age: 23.78±4.42 years). RPE and predicted VO_2max were determined during the cycle ergometer exercise test. Data were also obtained for height, weight, body mass index (BMI), hip and waist (WC) circumferences. Data analysis revealed VO_2max is correlated with WC (r=−0.571), weight (r=−0.521), waist-to-height ratio (WHtR) (r=−0.516), waist-to-hip ratio (WHR) (r=−0.487), and BMI (r=−0.47) in men, while, in women with WC (r=−0.581), weight (r=−0.571), WHtR (r=−0.545), BMI (r=−0.545), WHR (r=−0.473), and height (r=−0.287) (all P<0.05). Regression analysis showed WC was a significant predictor for VO_2max in men and women (r₂=32.6% vs. 33.7%). The receiver operating characteristic curve of WC showed 0.786 and 0.831 for men and women, respectively. WC or abdominal obesity is the strongest predictor for VO_2max, which is an indicator of aerobic fitness in Malaysian adults.

Obesity, Abdominal Obesity and Chronic Kidney Disease in Young Adults: A Nationwide Population-Based Cohort Study

Obesity has become a pandemic. It is one of the strongest risk-factors of new-onset chronic kidney disease (CKD). However, the effects of obesity and abdominal obesity on the risk of developing CKD in young adults has not been elucidated. From a nationwide health screening database, we included 3,030,884 young adults aged 20–39 years without CKD during a baseline examination in 2009–2010, who could follow up during 2013–2016. Patients were stratified into five levels based on their baseline body mass index (BMI) and six levels based on their waist circumference (WC; 5-cm increments). The primary outcome was the development of CKD. During the follow up, until 2016, 5853 (0.19%) participants developed CKD. Both BMI and WC showed a U-shaped relationship with CKD risk, identifying the cut-off values as a BMI of 21 and WC of 72 cm in young adults. The obesity group (odd ratio [OR] = 1.320, 95% confidence interval [CI]: 1.247–1.397) and abdominal obesity group (male WC ≥ 90, female WC ≥ 85) (OR = 1.208, 95%CI: 1.332–1.290) showed a higher CKD risk than the non-obesity or non-abdominal obesity groups after adjusting for covariates. In the CKD risk by obesity composite, the obesity displayed by the abdominal obesity group showed the highest CKD risk (OR = 1.502, 95%CI: 1.190–1.895), especially in those under 30 years old. During subgroup analysis, the diabetes mellitus (DM) group with obesity or abdominal obesity paradoxically showed a lower CKD risk compared with the non-obesity or non-abdominal obesity group. Obesity and abdominal obesity are associated with increased risk of developing CKD in young adults but a decreased risk in young adults with diabetes.

Optimal waist circumference cutoff values to predict cardiometabolic alterations in a Venezuela national representative sample. The EVESCAM study

BACKGROUND

Waist circumference (WC) value reflects abdominal adiposity, but the amount abdominal fat that is associated to cardiometabolic risk factors varies among ethnicities. Determination of metabolic abnormalities has not undergone a WC adaptation process in Venezuela.

AIMS

The aim of the study was (1) to determine the optimal WC cutoff value associated with ≥2 cardiometabolic alterations and (2) incorporating this new WC cutoff, to determine the prevalence of abdominal obesity and cardiometabolic risk factors related in Venezuela.

METHODS

The study was national population-based, cross-sectional, and randomized sample, from 2014 to 2017. To assess performance of WC for identifying cardiometabolic alterations, receiver operating characteristics curves, area under the curve (AUC), sensitivity, specificity, and positive likelihood ratios were calculated.

RESULTS

Three thousand three hundred eighty-seven adults were evaluated with mean age of 41.2 ± 15.8 years. Using the best tradeoff between sensitivity and specificity, WC cutoffs of 90 cm in men (sensitivity = 72.4% and specificity = 66.1%) and 86 cm in women (sensitivity = 76.2% and specificity = 61.4%) were optimal for aggregation of ≥2 cardiometabolic alterations. AUC was 0.75 in men and 0.73 in women using these new cutoffs. Prevalence of abdominal obesity and metabolic syndrome was 59.6% (95 CI; 57.5-61.7) and 47.6% (95 CI; 45.2-50.0), respectively. Cardiometabolic risk factors were associated with being men, higher age, adiposity, and living in northern or western regions.

CONCLUSION

The optimal WC values associated with cardiometabolic alterations were 90 cm in men and 86 cm in women. More than half of the Venezuelan population had abdominal obesity incorporating this new WC cutoff.

Incidence of Metabolic Syndrome in Young Japanese Adults in a 6-Year Cohort Study: The Uguisudani Preventive Health Large-Scale Cohort Study (UPHLS)

INTRODUCTION

To clarify the incidences of metabolic syndrome (MS) and risks in young Japanese adults by gender.

METHODS

A total of 58,901 adults who had undergone annual health check-ups in 2010 without a diagnosis of MS or missing data were divided into three age groups (20s through 40s) by gender. Participants were followed up for 6 years for new-onset MS according to Japanese criteria. The incidences of MS and risks were analyzed using the Cox proportional hazards model to adjust for confounding factors.

RESULTS

The incidences of MS per 1,000 person-years were 2.2, 5.5, and 10.2 for women aged in their 20s, 30s, and 40s, respectively, and 26.3, 40.5, and 57.4 in the respective men groups. Compared with the group aged in their 40s, the hazard ratios of new MS were 0.19 (95% confidence interval [CI], 0.13-0.29) for women in their 20s and 0.50 (95% CI, 0.41-0.61) for women in their 30s, and 0.46 (95% CI, 0.42-0.50) and 0.70 (95% CI, 0.66-0.73) for men in their 20s and 30s, respectively, after adjustment for lifestyle factors. For women, MS was associated with smoking in their 20s and 30s, and eating speed in their 30s, and for men, was associated with physical activity, eating speed, alcohol intake in their 20s and 30s, and smoking in their 30s.

CONCLUSION

Our findings suggest that the incidences of MS in the 20s and 30s are lower, but account for about 20-50% of women with MS and 50-70% of men with MS in their 40s. However, the data are not negligible and early lifestyle intervention for MS is necessary in young adults.

Associations of anemia and hemoglobin with hemoglobin A1c among non-diabetic workers in Japan

AIMS/INTRODUCTION

We examined the association between hemoglobin A1c (HbA1c) and anemia, which was categorized into three groups according to mean corpuscular volume (MCV), as well as the association between hemoglobin in the non-anemic range and HbA1c.

MATERIALS AND METHODS

We used the 2016 health checkup data from 36,422 workers without diabetes. Anemic people were divided into three groups based on MCV: <80, 80-90 and >90 fL. Non-anemic people were divided into four groups based on their hemoglobin levels. We carried out multiple linear regression models to estimate the means and 95% confidence intervals (CIs) of HbA1c.

RESULTS

For men, 0.2% had anemia with MCV <80 fL, 0.5% had anemia with MCV 80-90 fL, 0.9% had anemia with MCV >90 fL and 98.4% had no anemia. For women, the corresponding values were 6.1, 6.4, 2.8 and 84.7%, respectively. The adjusted mean HbA1c (%) values for men with anemia with MCV <80, 80-90 and >90 fL were 5.67 (95% CI 5.60-5.74), 5.58 (95% CI 5.54-5.62) and 5.41 (95% CI 5.37-5.44), respectively. Among men without anemia, HbA1c (%) increased from 5.36 (95% CI 5.34-5.39) in those with hemoglobin ≥17.5 mg/dL to 5.45 (95% CI 5.45-5.46) in those with hemoglobin 13.0 to <14.5 mg/dL (P for trend <0.001). The HbA1c values were higher in men with anemia with MCV <80 fL or MCV 80-90 fL, but lower in men with MCV >90 fL, compared with non-anemic men with hemoglobin 13.0 to <14.5 mg/dL (All P < 0.001). Similar findings were observed in women.

CONCLUSIONS

We observed elevated HbA1c among anemic people with MCV <80 fL or MCV 80-90 fL, and decreased HbA1c among anemic people with MCV >90 fL, suggesting that different types of anemia might influence HbA1c differently. In addition, non-anemic people with lower hemoglobin levels had higher HbA1c levels, suggesting that hemoglobin levels are in need of consideration when interpreting HbA1c values among non-anemic people.

The Impact of BMI Categories on Metabolic Abnormality Development in Chinese Adults Who are Metabolically Healthy: A 7-Year Prospective Study

PURPOSE

To determine what metabolic abnormalities develop frequently among metabolically healthy adults over time according to different baseline body mass index (BMI) categories.

PATIENTS AND METHODS

A prospective cohort study was performed on 10,805 adults, who were metabolically healthy at the time of the 2008 survey. Participants were divided into four groups: metabolically healthy obese (MHO), metabolically healthy overweight (MHOW), metabolically healthy normal-weight (MHN), and metabolically healthy underweight (MHU). Modified Poisson regression models were used to evaluate the relationship of BMI with the development of metabolic abnormalities. Association rule mining was used to identify the most frequent abnormalities that developed over time.

RESULTS

Compared with the MHN group, the adjusted relative risks of the MHO group were 1.57 (95% CI: 1.09-2.27) and 2.08 (95% CI: 1.59-2.73) for developing elevated fasting glucose and elevated blood pressure, respectively, after adjusting for lifestyle behaviours and dietary factors. At the end of follow-up, 33 (19.1%) MHO subjects and 342 (16.6%) MHOW subjects had elevated blood pressure as the predominant metabolic syndrome component, whereas 236 (9.0%) MHU subjects had elevated plasma glucose. The results were similar after stratification by sex.

CONCLUSION

MHO and MHOW subjects developed elevated blood pressure most frequently, and MHU subjects developed elevated blood glucose most commonly, regardless of sex.

Comparison of anthropometric measurements for prediction of the atherosclerosis and liver histology in young adults with nonalcoholic fatty liver disease

AIM

Anthropometry is a good evaluation tool that establishes the association between body fat distribution and metabolic risk factors precisely. The aim of this study was to test the association of anthropometric measurements with subclinical atherosclerosis and liver fibrosis.

METHODS

A total of 78 patients with nonalcoholic fatty liver disease (NAFLD) patients who had no known cardiovascular disease risk factors and 26 volunteered healthy controls were enrolled. Patients with suspected fatty liver underwent a liver biopsy. BMI, waist circumference (WC), hip circumference, and neck circumference (NC) were measured. To detect the presence of subclinical atherosclerosis, carotid intima-media thickness and carotid-femoral pulse wave velocity (cf-PWV) were examined.

RESULTS

NAFLD patients with fibrosis had higher NC, WC, and hip circumference levels, but no difference was observed between NAFLD patients without fibrosis and controls in these parameters. BMI was statistically different among the three groups (P < 0.05). After adjusting for confounding risk factors, the only significant parameter associated with histologic severity of NAFLD was WC, with odds ratio of 1.10. All anthropometric measurements were correlated positively with fibrosis, cf-PWV, and each other. While the association between BMI and cf-PWV remained significant, WC was found to be an independent risk factor for carotid intima-media thickness after adjustment of known cardiovascular risk factors.

CONCLUSION

WC is the strongest predictor of liver fibrosis as the anthropometric indexes in patients with NAFLD. NC can be used as an additional useful screening test for the primary evaluation of patients with NAFLD, even if it is not an independent risk factor.

Metabolic syndrome is a predictor of decreased renal function among community-dwelling middle-aged and elderly Japanese

PURPOSE

Metabolic syndrome (MetS) is increasing worldwide with the continuous increase in obesity prevalence. Chronic kidney disease (CKD) is also a major public health problem, but there is controversy over whether baseline MetS is a predictor of decreased renal function among Japanese community-dwelling middle-aged and elderly Japanese.

METHODS

We conducted a prospective cohort study designed as part of the Nomura study. We recruited a random sample of 410 men aged 68 ± 8 (mean ± standard deviation; range, 50-95) years and 549 women aged 69 ± 7 (50-84) years during their annual health examination in a single community. We examined the relationship between baseline MetS and renal dysfunction after a 3-year evaluation based on estimated glomerular filtration rate (eGFR_CKDEPI) using the CKD-EPI equations modified by the Japan coefficient. CKD was defined as dipstick-positive proteinuria (> or = 1 +) or a low eGFR_CKDEPI (< 60 mL/min/1.73 m²).

RESULTS

Of the 959 participants, 413 (43.1%) had MetS at baseline. Annual eGFR decline rate was significantly greater in those with MetS than in those without MetS, and the annual eGFR decline rate of < - 1.2 mL/min/1.73 m²/year increased significantly in relation to presence of baseline MetS, especially low HDL cholesterol (HDL-C). Moreover, the incidence rate of CKD after 3 years was 13.5% and increased significantly in relation to presence of baseline MetS, especially its components such as elevated HbA1c. The multivariate-adjusted odd ratio (OR) for CKD in participants with MetS versus those without MetS was 1.55 (0.99-2.43). The multivariate-adjusted ORs for rapid annual eGFR decline rate were significantly high in patients aged ≥ 65 years and presence of medication, regardless of gender and eGFR value.

CONCLUSIONS

Low HDL-C and elevated HbA1c levels correlated significantly with eGFR decline in a short period of 3 years. MetS also showed a significant association with eGFR decline. This study suggests the importance of low HDL-C and elevated HbA1c in the effect of MetS on eGFR decline rather than obesity among Japanese community-dwelling middle-aged and elderly Japanese without CKD.

Polycystic Ovarian Syndrome: Correlation between clinical hyperandrogenism, anthropometric, metabolic and endocrine parameters

OBJECTIVE

To evaluate the correlation between clinical hyperandrogenism-hirsutism assessed by modified Ferriman-Gallwey (F-G) score, anthropometric, metabolic and endocrine parameters among PCOS infertile women.

METHODS

This observational study after approval of FRC & ERC of BUMDC was conducted from September 2018-March 2019. It included seventy women aged 20-40 years who presented in infertility clinic of a local Hospital in Karachi. After written informed consent participants were enrolled as per the inclusion criteria of the study and evaluated for cyclical pattern (oligomenorrhoea, amenorrhoea, polymenorrhea), physical (weight, height, BMI), anthropometric, (waist circumference, hip circumference, waist to hip ratio, hirsutism), metabolic (carbohydrate, lipid & protein) and endocrine parameters (serum FSH, LH, LH/FSH ratio, serum testosterone, prolactin and progesterone level). Hirsutism was assessed by visual method through modified F-G score and Pearson correlation was determined between hirsutism and other study parameters.

RESULTS

A positive Pearson correlation is found between hirsutism and body weight, BMI, waist and hip circumference, waist to hip ratio (WHR), very low density lipoprotein, cholesterol, triglycerides and testosterone levels.

CONCLUSION

Hirsutism has correlation with anthropometric, metabolic and hyperandrgenic disorders in PCOS infertile women as assessed by modified F-G score.

Low serum creatinine and risk of diabetes: The Japan Epidemiology Collaboration on Occupational Health Study

AIMS/INTRODUCTION

We examined a prospective association between serum creatinine levels and diabetes.

MATERIALS AND METHODS

The present study included 31,343 male workers without diabetes, and aged between 20 and 64 years at baseline. We calculated the cumulative average of their serum creatinine over the study period. We defined diabetes as either glycated hemoglobin levels ≥6.5%, random glucose levels ≥200 mg/dL, fasting glucose levels ≥126 mg/dL or receiving antidiabetic treatment. Cox proportional hazards regression analysis was carried out to estimate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

With a median observation of 7.7 years, 2,509 participants developed diabetes. After adjusting for age, smoking, body mass index, hypertension and dyslipidemia, lower cumulative average serum creatinine levels were related to a greater diabetes risk: HRs were 1.56 (95% CI 1.35-1.82), 1.22 (1.09-1.35) and 1.06 (0.96-1.17) for the participants with serum creatinine <0.70, 0.70-0.79 and 0.80-0.89 mg/dL, respectively, compared with those with 0.90-1.20 mg/dL (P for trend <0.001). The serum creatinine-diabetes association was more pronounced among older adults (serum creatinine <0.70 vs 0.90-1.20 mg/dL, HR 1.66, 95% CI 1.37-2.00) than younger adults (HR 1.32, 95% CI 1.02-1.71; P for interaction by age group = 0.001).

CONCLUSIONS

Low serum creatinine is associated with an increased risk of diabetes. Screening serum creatinine levels can be used to identify those who are at high risk of diabetes.

Usefulness of waist-to-height ratio in screening incident metabolic syndrome among Japanese community-dwelling elderly individuals

This study examined a range of anthropometric indices and their relationships with metabolic syndrome (MetS). Despite recommendations that central obesity assessment should be employed as a marker of metabolic health, there is no consensus regarding the protocol for measurement. The present study included 720 men aged 71 ± 8 years and 919 women aged 71 ± 7 years from a rural village. We examined the relationship between anthropometric indices {e.g., body mass index (BMI), waist-to-height ratio (WHtR), waist-to-hip ratio (WHpR)}, and MetS based on the modified criteria of the National Cholesterol Education Program’s Adult Treatment Panel (NCEP-ATP) III report in a cross-sectional (N = 1,639) and cohort (N = 377) data. A receiver operating curve (ROC) analysis was performed to determine the optimal cut-off value and best discriminatory value of each of these anthropometric indices to predict MetS. In the cross-sectional study, WHtR as well as BMI and WHpR showed significantly predictive abilities for MetS in both genders; and WHtR showed the strongest predictive ability for the presence of MetS. Also in the cohort study, WHtR as well as BMI and WHpR showed significantly predictive abilities for incident MetS in both genders, and in men WHtR showed the strongest predictive ability for incident MetS, but in women BMI showed the strongest predictive ability. In the cross-sectional study, the optimal WHtR cutoff values were 0.52 (sensitivity, 71.0%; specificity, 77.9%) for men and 0.53 (sensitivity, 79.8%; specificity, 75.7%) for women. In the cohort study, the optimal WHtR values were 0.50 (sensitivity, 60.7%; specificity, 73.2%) for men and 0.50 (sensitivity, 75.0%; specificity, 56.1%) for women. Increased WHtR was significantly and independently associated with prevalence of MetS in both genders. These results suggest that WHtR is a useful screening tool for determining metabolic risk in Japanese elderly community dwelling individuals.

Obesity and risk of hearing loss: A prospective cohort study

BACKGROUND & AIMS

The existing yet limited prospective studies reported conflicting results about obesity and hearing loss. We investigated the prospective association between obesity and hearing loss in a large-scale Japanese working population, as well as the association between metabolic phenotype and hearing loss.

METHODS

The study included 48,549 employees aged 20-64 years and free of hearing loss at baseline. Pure-tone audiometric testing was performed annually to identify hearing loss at 1 and 4 kHz. Cox proportional hazards regression was used to investigate the risk of hearing loss associated with body mass index (BMI) and metabolic phenotype (based on a BMI of ≥25.0/<25.0 kg/m² and presence/absence of ≥2 components of metabolic syndrome, except waist circumference). Baseline and updated information were obtained from annual health checkups.

RESULTS

With a median follow-up of 7 years, 1595 and 3625 individuals developed unilateral hearing loss at 1 and 4 kHz, respectively. The adjusted hazard ratios (HR) for hearing loss at 1 kHz were 1.21 (1.08, 1.36) and 1.66 (1.33, 2.08) for those with BMI 25.0-29.9 kg/m² and BMI ≥30.0 kg/m², respectively, compared to individuals with BMI <25.0 kg/m². For hearing loss at 4 kHz, the corresponding HRs were 1.14 (1.05, 1.23) and 1.29 (1.09, 1.52). Compared with metabolically healthy non-obese individuals, the adjusted HRs for hearing loss at 1 kHz were 1.19 (1.03, 1.39), 1.27 (1.01, 1.61), and 1.48 (1.25, 1.76) for unhealthy non-obese, healthy obese, and unhealthy obese individuals, respectively. For hearing loss at 4 kHz, the corresponding HRs were 1.13 (1.04, 1.25), 1.21 (1.04, 1.41), and 1.26 (1.12, 1.41).

CONCLUSIONS

Overweight and obesity are associated with an increased risk of hearing loss, and metabolically unhealthy obesity may confer additional risk.

Total bilirubin independently predicts incident metabolic syndrome among community-dwelling women

BACKGROUND

Metabolic syndrome (MetS) is related to the increased risk of major cardiovascular diseases (CVD). The link between high serum total bilirubin (TBL) is cross-sectionally related to MetS and its components. However, whether serum TBL predicts incidence of MetS and its components remains inconclusive.

METHODS

The present study included 893 women aged 70 ± 9 years from a rural village. We examined the relationship between serum TBL and MetS based on the modified criteria of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP) III report in a cross-sectional (N = 893) and cohort (N = 288) data.

RESULTS

In the cross-sectional study, serum TBL (β = 0.536, p < 0.001) as well as age, alcohol consumption, exercise habits, history of CVD, SUA, GGT, and ALT was significantly and dependently associated with number of MetS components, but in the cohort study serum TBL was not associated with number of MetS components. Compared with the 1st tertile of serum TBL (0.20-0.55 mg/dL), multivariate-adjusted odds ratio (95% confidence interval) for the 2nd -3rd tertiles of serum TBL (0.54-2.00 mg/dL) was 0.70 (0.51-0.95) in the cross-sectional study and 0.41 (0.21-0.81) in the cohort study.

CONCLUSIONS

Our data demonstrated an independently negative association between serum TBL and MetS in Japanese community-dwelling women.

Serum Uric Acid to Creatinine Ratio Independently Predicts Incident Metabolic Syndrome Among Community-Dwelling Persons

BACKGROUND

Metabolic syndrome (MetS) is related to the increased risk of major cardiovascular disease. The link between high serum uric acid (SUA) and creatinine (Cr) levels is causally related to MetS and its components. However, whether renal function-normalized SUA [i.e., SUA to Cr ratio (SUA/Cr)] predicts incident MetS and its components remains inconclusive.

MATERIALS AND METHODS

We conducted a prospective cohort study designed as part of the Nomura study. The subjects comprised 447 men ages 68 ± 10 years and 625 women ages 68 ± 9 years from a rural village, and 155 (34.7%) men and 310 women (49.6%) had MetS at baseline. We found participants who underwent a similar examination 3 years later and analyzed the relationship between baseline SUA/Cr and incident MetS defined according to the modified criteria of the National Cholesterol Education Program-Adult Treatment Panel III (NCEP ATP III).

RESULTS

One hundred forty-nine (33.3%) men and 286 (45.8%) women had MetS after a 3-year follow-up. Multiple linear regression analysis was performed to evaluate the contribution of possible confounding factors for MetS. In women only, baseline SUA/Cr, as well as baseline number of MetS and age, was significantly and independently associated with the number of MetS components at follow-up. The multivariable-adjusted odds ratios (95% confidence interval) for incident MetS across three quartiles of baseline SUA/Cr (1st-2nd, 3rd, and 4th) were 1.00, 1.62 (0.97-2.69), and 2.07 (1.20-3.56), respectively. Furthermore, when subjects were stratified by age, estimated glomerular filtration rate (eGFR), and presence of baseline MetS, baseline SUA/Cr was also a significant and independent determinant for incident MetS in women with age ≥60 years, eGFR ≥70 mL/min/1.73 m², and presence of baseline MetS.

CONCLUSIONS

Baseline SUA/Cr was significantly associated with incident MetS among community-dwelling women.

Cumulative Risk of Type 2 Diabetes in a Working Population: The Japan Epidemiology Collaboration on Occupational Health Study

BACKGROUND

We estimated the cumulative risk of type 2 diabetes from age 30 to 65 years in a large working population in Japan.

METHODS

We used data from the Japan Epidemiology Collaboration on Occupational Health Study. Participants (46,065 men and 7,763 women) were aged 30-59 years, free of diabetes at baseline, and followed up for a maximum of 7 years. Incident type 2 diabetes was defined based on fasting and casual glucose, glycated hemoglobin, and current medical treatment for type 2 diabetes. We calculated the sex-specific cumulative risk of type 2 diabetes using the Practical Incidence Estimator macro, which was created to produce several estimates of disease incidence for prospective cohort studies based on a modified Kaplan-Meier method.

RESULTS

During 274,349 person-years of follow-up, 3,587 individuals (3,339 men and 248 women) developed type 2 diabetes. The cumulative risk was 34.7% (95% confidence interval, 33.1-36.3%) for men and 18.6% (95% confidence interval, 15.5-21.7%) for women. In BMI-stratified analysis, obese (BMI ≥30 kg/m2) and overweight (BMI 25-29.9 kg/m2) men and women had a much higher cumulative risk of type 2 diabetes (obese: 77.3% for men and 64.8% for women; overweight: 49.1% and 35.7%, respectively) than those with BMI <25 kg/m2 (26.2% and 13.4% for men and women, respectively).

CONCLUSIONS

The present data highlight the public health burden of type 2 diabetes in the working population. There is a need for effective programs for weight management and type 2 diabetes screening, especially for young obese employees, to prevent or delay the development of type 2 diabetes.

Development and validation of risk models to predict the 7-year risk of type 2 diabetes: The Japan Epidemiology Collaboration on Occupational Health Study

AIMS/INTRODUCTION

We previously developed a 3-year diabetes risk score in the working population. The objective of the present study was to develop and validate flexible risk models that can predict the risk of diabetes for any arbitrary time-point during 7 years.

MATERIALS AND METHODS

The participants were 46,198 Japanese employees aged 30-59 years, without diabetes at baseline and with a maximum follow-up period of 8 years. Incident diabetes was defined according to the American Diabetes Association criteria. With routine health checkup data (age, sex, abdominal obesity, body mass index, smoking status, hypertension status, dyslipidemia, glycated hemoglobin and fasting plasma glucose), we developed non-invasive and invasive risk models based on the Cox proportional hazards regression model among a random two-thirds of the participants, and used another one-third for validation.

RESULTS

The range of the area under the receiver operating characteristic curve increased from 0.73 (95% confidence interval 0.72-0.74) for the non-invasive prediction model to 0.89 (95% confidence interval 0.89-0.90) for the invasive prediction model containing dyslipidemia, glycated hemoglobin and fasting plasma glucose. The invasive models showed improved integrated discrimination and reclassification performance, as compared with the non-invasive model. Calibration appeared good between the predicted and observed risks. These models performed well in the validation cohort.

CONCLUSIONS

The present non-invasive and invasive models for the prediction of diabetes risk up to 7 years showed fair and excellent performance, respectively. The invasive models can be used to identify high-risk individuals, who would benefit greatly from lifestyle modification for the prevention or delay of diabetes.

Gender Differences in the Clinical Features of Sleep Apnea Syndrome

Objective Sleep apnea syndrome is more prevalent among men than women and is frequently accompanied by metabolic syndrome (MetS). However, gender differences in the effect of sleep-disordered breathing (SDB) leading to the risk of MetS remain unclear. The aim of our study was to investigate the clinical characteristics of SDB in women and the differential influence of SDB on MetS between genders. Methods In a single-center retrospective study, we compared the data of 1,809 consecutive SDB patients by gender to clarify the characteristics of sleep disorders in women. We also compared the prevalence of MetS and its related abnormalities by gender. A logistic regression analysis was used to determine the contributory factors for MetS. Results The mean age and proportion of patients over 50 years of age were higher in women than in men. SDB was milder in women than in men according to polysomnography findings. Elevated Hemoglobin A1c levels and hyperlipidemia were less frequent in women than in men. The MetS prevalence was similar in women and men (30.0% vs. 35.2%). A logistic regression analysis showed that the apnea-hypopnea index (AHI) was an independent risk factor for MetS in both genders, but that female gender was independently associated with a decreased prevalence of MetS and its related abnormalities. Conclusion Female SDB patients tend to be older with milder apnea and sleepiness than male SDB patients. A higher AHI is a significant risk factor for MetS in both genders, although female gender is an independent inhibitory factor for developing MetS in SDB patients.

Predictive capacity of indicators of adiposity in the metabolic syndrome in elderly individuals

ABSTRACT Objective To evaluate the predictive ability of adiposity indicators as MetS predictors in elderly individuals. Methods Cross-sectional study enrolled in the Estratégia Saúde da Família (Family Health Strategy). Anthropometric measurements were measured. Body Mass Index, Waist-Hip Ratio, Waist-Height Ratio, Conicity Index and Body Adiposity Index were calculated. Blood was collected and resting blood pressure was measured. MetS was classified according to the harmonizing criteria. The predictive ability of anthropometric variables was evaluated using Receiver Operating Characteristic curves. Results Regarding male individuals, our research indicates that the BMI, Waist-Height Ratio and Waist Hip Ratio are better predictors and they are equivalent to each other. As for female individuals, results show that the Body Mass Index and Waist-Height Ratio are better predictors and equivalent to each other. Conclusion Waist-Height Ratio and Body Mass Index are good MetS predictors for elderly individuals, especially among men. More research in this area is important. Comitê de Ética em Pesquisa com Seres Humanos da Universidade Federal de Viçosa. (Viçosa University Ethics Committee in Research with Human Beings) (nº 039/2011).

Sleep Duration Modifies the Association of Overtime Work With Risk of Developing Type 2 Diabetes: Japan Epidemiology Collaboration on Occupational Health Study

Background

Evidence linking working hours and the risk of type 2 diabetes mellitus (T2DM) is limited and inconsistent in Asian populations. No study has addressed the combined association of long working hours and sleep deprivation on T2DM risk. We investigated the association of baseline overtime work with T2DM risk and assessed whether sleep duration modified the effect among Japanese.

Methods

Participants were Japanese employees (28,489 men and 4,561 women) aged 30–64 years who reported overtime hours and had no history of diabetes at baseline (mostly in 2008). They were followed up until March 2014. New-onset T2DM was identified using subsequent checkup data, including measurement of fasting/random plasma glucose, glycated hemoglobin, and self-report of medical treatment. Hazard ratios (HRs) of T2DM were estimated using Cox regression analysis. The combined association of sleep duration and working hours was examined in a subgroup of workers (n = 27,590).

Results

During a mean follow-up period of 4.5 years, 1,975 adults developed T2DM. Overtime work was not materially associated with T2DM risk. In subgroup analysis, however, long working hours combined with insufficient sleep were associated with a significantly higher risk of T2DM (HR 1.42; 95% CI, 1.11–1.83), whereas long working hours with sufficient sleep were not (HR 0.99; 95% CI, 0.88–1.11) compared with the reference (<45 hours of overtime with sufficient sleep).

Conclusions

Sleep duration modified the association of overtime work with the risk of developing T2DM. Further investigations to elucidate the long-term effect of long working hours on glucose metabolism are warranted.

Intensity of Leisure-Time Exercise and Risk of Depressive Symptoms Among Japanese Workers: A Cohort Study

Background

Data on the effect of physical activity intensity on depression is scarce. We investigated the prospective association between intensity of leisure-time exercise and risk of depressive symptoms among Japanese workers.

Methods

The participants were 29,052 employees (24,653 men and 4,399 women) aged 20 to 64 years without psychiatric disease including depressive symptoms at health checkup in 2006–2007 and were followed up until 2014–2015. Details of leisure-time exercise were ascertained via a questionnaire. Depressive states were assessed using a 13-item questionnaire. Multivariable-adjusted hazard ratio of depressive symptoms was estimated using Cox regression analysis.

Results

During a mean follow-up of 5.8 years with 168,203 person-years, 6,847 workers developed depressive symptoms. Compared with workers who engaged in no exercise during leisure-time (0 MET-hours per week), hazard ratios (95% confidence intervals) associated with >0 to <7.5, 7.5 to <15.0, and ≥15.0 MET-hours of leisure-time exercise were 0.88 (0.82–0.94), 0.85 (0.76–0.94), and 0.78 (0.68–0.88) among workers who engaged in moderate-intensity exercise alone; 0.93 (0.82–1.06), 0.82 (0.68–0.98), and 0.83 (0.71–0.98) among workers who engaged in vigorous-intensity exercise alone; and 0.96 (0.80–1.15), 0.80 (0.67–0.95), and 0.76 (0.66–0.87) among workers who engaged in both moderate- and vigorous-intensity exercise with adjustment for age, sex, lifestyles, work-related and socioeconomic factors, and body mass index. Additional adjustment for baseline depression score attenuated the inverse association, especially among those who engaged in moderate-intensity exercise alone.

Conclusions

The results suggest that vigorous-intensity exercise alone or vigorous-intensity combined with moderate-intensity exercise would prevent depressive symptoms among Japanese workers.

Metabolic Syndrome Over 4 Years Before the Onset of Cardiovascular Disease - Nested Case-Control Study

BACKGROUND

We investigated the risk of cardiovascular disease (CVD) with duration of metabolic syndrome (MetS) for the past 4 years before the CVD event.Methods and Results:We performed a nested case-control study within the Japan Epidemiology Collaboration on Occupational Health Study. A total of 139 registered cases of CVD and 561 self-reported cases of CVD were identified and matched individually on age, sex, and worksite with 695 and 2,803 controls, respectively. MetS was defined by the Joint Interim Statement definition. The odds ratio (95% confidence interval) for registered CVD was 4.7 (2.9, 7.5) for people with persistent MetS (positive for MetS for ≥3 assessments) and 1.9 (1.1, 3.3) for those with intermittent MetS (positive for MetS for 1-2 assessments), compared with people without MetS during the past 4 years before the event/index date (P for trend <0.001). The corresponding odds ratio for self-reported CVD was 2.7 (2.2, 3.5) and 1.8 (1.4, 2.3) (P for trend <0.001). The association with MetS duration was stronger for myocardial infarction than for other CVD subtypes. Similar results were obtained when using the Japanese MetS criteria.

CONCLUSIONS

The risk of CVD increases with increasing MetS duration. These findings contribute to risk stratification and encourage lifestyle modification for people with MetS to minimize their health risk.

Gender Differences in Lifestyle Factors Associated with Metabolic Syndrome and Preliminary Metabolic Syndrome in the General Population: The Watari Study

Objective In Japan, metabolic syndrome (MetS) and preliminary metabolic syndrome (preMetS) are more prevalent in men; however, it remains unclear whether the relationship between these metabolic disorders and lifestyle factors is similar between genders. Methods We examined waist circumference, blood pressure, fasting blood, and various lifestyle factors in 3,166 individuals aged from 30-79 years of age from the Japanese general population. MetS was diagnosed on the basis of central obesity - assessed by waist circumference - plus two or more of the following cardio-metabolic risks according to Japanese criteria: high blood pressure, hyperglycemia, and lipid abnormality. Central obesity plus one of the risks was defined as preMetS. Results Men had a significantly higher prevalence of MetS (23.3% vs. 8.7%, p<0.001) and preMetS (21.2% vs. 10.2%, p<0.001) than women. An age-adjusted logistic regression analysis revealed that heavy drinkers were associated with an increased probability of MetS (odds ratio, 1.91: 95% confidence interval, 1.29-2.83) and preMetS (1.69: 1.11-2.58); fast eaters were also related to preMetS (1.83: 1.33-2.55) and MetS (1.55: 1.12-2.15) in men. Lacking regular exercise was significantly associated with preMetS (1.38: 1.03-1.85), but not MetS. In women, preMetS was significantly associated with fast eaters and lacking regular exercise (1.44: 1.01-2.07 and 1.41: 1.02-1.96, respectively); a stepwise increase in each odds ratio (2.02: 1.40-2.91 and 1.47: 1.03-2.09, respectively) was also observed for MetS. Conclusion The relationships between lifestyle factors and MetS or preMetS differed between men and women, which suggests the need for gender-specific lifestyle modification to effectively prevent MetS.

Metabolic syndrome components and diabetes incidence according to the presence or absence of impaired fasting glucose: The Japan Epidemiology Collaboration on Occupational Health Study

Background

We prospectively examined the association of diabetes risk with the number of metabolic abnormalities, as well as their combinations, according to the presence or absence of impaired fasting glucose (IFG) in a large-scale Japanese working population.

Methods

Participants included 55,271 workers at 11 companies who received periodic health check-ups between 2008 and 2013. The metabolic syndrome (MetS) components were defined using the 2009 Joint Interim Statement. IFG was defined as fasting plasma glucose 5.6–6.9 mmol/L. Diabetes newly diagnosed after the baseline examination was defined according to the American Diabetes Association criteria. We calculated the hazard ratios (HRs) for diabetes incidence using the Cox proportional hazards model.

Results

During the follow-up period (median 4.95 years), 3183 subjects developed diabetes. In individuals with normal fasting glucose levels, the risk of diabetes increased steadily with the increasing number of MetS components; the multivariable-adjusted HRs for incident diabetes for the number of MetS components were 2.0, 4.3, 7.0, and 10.0 for one, two, three, or four MetS components, respectively, compared with the absence of components. A similar association was observed among individuals with IFG; the corresponding HRs were 17.6, 23.8, 33.9, and 40.7. The combinations that included central obesity appeared to be more strongly associated with diabetes risk than other combinations with the same number of MetS components within the same glucose status.

Conclusions

Our findings indicate that risk stratification of individuals by the presence or absence of IFG and the number of MetS components can detect individuals with a high risk of diabetes.

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We examined diabetes risk by the number and combination of metabolic abnormalities.

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Diabetes risk increased with the number of abnormalities for a given glucose status.

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The combinations that included central obesity were strongly associated with diabetes.

Comorbidities according to airflow limitation severity: data from comprehensive health examination in Japan

Objectives

The present study aimed to investigate the relationship between airflow limitation (AL) severity and comorbidities in comprehensive health examination.

Methods

This cross-sectional study included 6661 men and 6044 women aged 40–89 who underwent a lung function test during medical checkups. AL was defined as forced expiratory volume in 1 s/forced vital capacity of < 0.7. Logistic regression analysis was used to assess the association between AL severity and the presence of comorbidities.

Results

When compared with the normal lung function group, subjects with AL had a higher prevalence of lung cancer (odd ratio (OR) 9.88, 95% confidence interval (CI) 3.88–25.14) in men, hypertension (OR 1.63, 95% CI 1.26–2.10) in women, diabetes and hyperglycemia (OR 1.23, 95% CI 1.02–1.49 in men, OR 1.61, 95% CI 1.18–2.20 in women) in men and women after adjusting for potential confounders. In men, lung cancer and MetS (the Joint Interim Statement: JIS) were significantly associated with moderate-to-very severe AL after adjustment. In women, hypertension, diabetes and hyperglycemia, MetS (JIS), and MetS (the Japanese Committee of the Criteria for MetS: JCCMS) were significantly associated with mild AL after adjustment. Hypertension was significantly associated with moderate-to-very severe AL after adjustment in women.

Conclusions

Significant relationships were found between AL severity and the presence of comorbid lung cancer in men, hypertension in women, diabetes and hyperglycemia, and MetS in men and women. Knowledge of comorbidities associated with AL should be widely publicized to raise the awareness of chronic obstructive pulmonary disease (COPD).

Duration and degree of weight change and risk of incident diabetes: Japan Epidemiology Collaboration on Occupational Health Study

We prospectively examined diabetes risk in association with a summary measure of degree and duration of weight change. The study participants were 51,777 employees from multiple companies in Japan, who were aged 30-59years, free of diabetes at baseline, and followed up for 7years (2008-2015). Exposure was cumulative body mass index (BMI)-years, which was defined as the area of BMI units above or below baseline BMI during follow-up, and was treated as a time-dependent variable in the Cox proportional hazards regression models. During the 263,539 person-years of follow-up, 3465 participants developed diabetes. The adjusted hazard ratio (HR) of diabetes for a 1-unit increase in cumulative BMI-years was 1.11 (95% confidence interval (CI): 1.09, 1.12). The association was more pronounced among overweight (HR=1.11; 95% CI: 1.08, 1.14) and obese (HR=1.12; 95% CI: 1.08, 1.15) adults compared with normal- and under-weight (HR=1.07; 95% CI: 1.03, 1.11) adults (P for interaction of cumulative BMI-years X baseline BMI-group=0.002). The association of higher cumulative BMI-years with incident diabetes did not substantially differ by metabolic phenotype. The present results emphasize the importance of avoiding additional weight gain over an extended period of time for the prevention of type 2 diabetes, especially among overweight and obese adults, irrespective of metabolic health status.