Population Approaches Targeting Metabolic Syndrome Focusing on Japanese Trials

Associating Liver Enzymes and Their Interactions with Metabolic Syndrome Prevalence in a Japanese Working Population

Background: Serum gamma-glutamyltransferase (γ-GT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels often increase in metabolic diseases. Objective: This study was conducted to determine which liver enzymes are strongly associated with metabolic syndrome (MetS), how they interact to produce different probability estimates, and what cutoff levels should be used to guide clinical decision-making. Methods: The researchers examined the insurance-based medical checkup data of 293,610 employees ≥35 years years of age, who underwent medical checkups between April 1, 2016, and March 31, 2017. Liver enzyme levels were grouped into quartiles. The association and interaction of liver enzymes with MetS were examined using logistic regression, and receiver operating characteristic (ROC) analyses were used to determine the optimal cutoff values for each liver enzyme in detecting the prevalence of MetS. Results: High levels of γ-GT and ALT were more strongly associated with MetS than AST. At various levels, the tested liver enzymes were found interactive, and associated with the likelihood of MetS prevalence. ROC analysis underscored the significance of all liver enzymes in predicting the development of MetS. The cutoff values for each liver enzyme were determined. Conclusion: This findings of this study directly support the identification of MetS risks within the population, prioritize prevention strategies, and potentially inform policy formulation.

Prevalence and correlates of metabolic syndrome among women living in urban slums, Mysore, India

Metabolic Syndrome (MetSyn) is a predictor of cardiovascular disease (CVD). About a third of urban Indians suffer from MetSyn. This study examined the prevalence of MetSyn among women living in urban slums. A cross-sectional survey was carried out between October 2017 and May 2018 among a non-probability sample of slum-dwelling women, 40-64 years of age, in six government-designated slums in Mysore, India. Data were collected on demographics, diet, behavioral risks, anthropometry, blood pressure, serum glucose, hemoglobin A1c, and serum lipids. The study used a definition of MetSyn from the International Diabetes Federation Task Force on Epidemiology and Prevention with an HbA1c measure for average blood glucose. About two-fifths of the 607 participants had MetSyn (41.5%; 95% CI: 37.7-45.5). Of those, 40.9% met three criteria, 38.1% four, and 25.0%, all five criteria. Elevated BP was the most prevalent MetSyn factor (79.6%), followed by increased waist circumference (54.5%), low HDL (50.1%), elevated Hb A1c (37.1%), and elevated triglycerides (36.1%). Odds for MetSyn were 1.52 times greater for those who were 50-59 years of age compared with those 40-49 years of age (adjusted odds ratio[AOR]:1.52; 95% CI:0.96-2.40). Women with mobility issues had 1.29 times higher odds of MetSyn than those without it (AOR: 0.76, 95% CI: 0.96, 1.75). Housewives had 1.29 times greater odds of MetSyn (AOR: 1.29, 95% CI: 1.00, 1.67). There is a high prevalence of MetSyn among urban slum-dwelling women in Mysore. There is a need for interventions aimed at reducing CVD risk factors in this population.

Association of the COVID-19 pandemic with changes in objectively measured sedentary behaviour and adiposity

BACKGROUND

Several studies have reported that the coronavirus disease (COVID-19) pandemic has increased sedentary behaviour and obesity; however, these analyses used self-reported data, and the association between sedentary behaviour and visceral fat and adipocytokines during the COVID-19 pandemic remains unclear. We aimed to investigate the association of the COVID-19 pandemic with objectively measured sedentary behaviour and these obesity-related factors.

METHODS

Longitudinal analysis was conducted on 257 Japanese participants who underwent health check-ups in 2018 before and in 2020 during the COVID-19 pandemic. For both time points, sedentary behaviour was measured using an accelerometer for at least 7 days, visceral fat area (VFA) was measured using abdominal bioelectrical impedance analysis, and blood adiponectin level was measured using latex agglutination turbidimetric immunoassay. Multiple linear regression was performed to determine the association between sedentary behaviour and these outcomes.

RESULTS

Compared with data in 2018, sedentary behaviour and VFA were significantly increased (P < 0.001, P = 0.006) whereas adiponectin level was significantly decreased (P < 0.001) in 2020. Increased sedentary behaviour was significantly associated with an increase in VFA (β = 3.85, 95% CI 1.22-6.49, P = 0.004) and a decrease in adiponectin level (β = -0.04, 95% CI -0.06 to -0.01, P = 0.005). However, the association of sedentary behaviour with adiponectin level was not significant after considering the effects of VFA.

CONCLUSIONS

The COVID-19 pandemic was associated with objectively measured sedentary behaviour and obesity-related factors in Japanese adults. Additionally, an increase in sedentary behaviour was associated with an increase in VFA, whereas the association of sedentary behaviour with adiponectin was partly mediated by VFA. These results suggest that avoiding increasing sedentary time is important to prevent visceral adiposity thereby ameliorating adiponectin, especially during behavioural limitations such as the COVID-19 pandemic.

Visceral fat and attribute-based medicine in chronic kidney disease

Visceral adipose tissue plays a central role in obesity and metabolic syndrome and is an independent risk factor for both cardiovascular and metabolic disorders. Increased visceral adipose tissue promotes adipokine dysregulation and insulin resistance, leading to several health issues, including systemic inflammation, oxidative stress, and activation of the renin-angiotensin-aldosterone system. Moreover, an increase in adipose tissue directly and indirectly affects the kidneys by increasing renal sodium reabsorption, causing glomerular hyperfiltration and hypertrophy, which leads to increased proteinuria and kidney fibrosis/dysfunction. Although the interest in the adverse effects of obesity on renal diseases has grown exponentially in recent years, the relationship between obesity and renal prognosis remains controversial. This may be attributed to the long clinical course of obesity, numerous obesity-related metabolic complications, and patients' attributes. Multiple individual attributes influencing the pathophysiology of fat accumulation make it difficult to understand obesity. In such cases, it may be effective to elucidate the pathophysiology by conducting research tailored to individual attributes from the perspective of attribute-based medicine/personalized medicine. We consider the appropriate use of clinical indicators necessary, according to attributes such as chronic kidney disease stage, level of visceral adipose tissue accumulation, age, and sex. Selecting treatments and clinical indicators based on individual attributes will allow for advancements in the clinical management of patients with obesity and chronic kidney disease. In the clinical setting of obesity-related nephropathy, it is first necessary to accumulate attribute-based studies resulting from the accurate evaluation of visceral fat accumulation to establish evidence for promoting personalized medicine.

Comparison of obesity-related indicators for identifying metabolic syndrome among normal-weight adults in rural Xinjiang, China

Background

This study aimed to compare the ability of certain obesity-related indicators to identify metabolic syndrome (MetS) among normal-weight adults in rural Xinjiang.

Methods

A total of 4315 subjects were recruited in rural Xinjiang. The questionnaire, biochemical and anthropometric data were collected from them. Binary logistic regression was used to analyze the association between the z-score of each index and MetS. The area under the receiver-operating characteristic (ROC) curves were used to compare the diagnostic ability of each index. According to the cut-off value of each index, nomogram models were established and their diagnostic ability were evaluated.

Results

After adjusting for confounding factors, each indicator in different genders was correlated with MetS. Triglyceride-glucose index (TyG index) showed the strongest association with MetS in both males (OR = 3.749, 95%CI: 3.173–4.429) and females (OR = 3.521,95%CI: 2.990–4.148). Lipid accumulation product (LAP) showed the strongest diagnostic ability in both males (AUC = 0.831, 95%CI: 0.806–0.856) and females (AUC = 0.842, 95%CI: 0.820–0.864), and its optimal cut-off values were 39.700 and 35.065, respectively. The identification ability of the TyG index in different genders (males AUC: 0.817, females AUC: 0.817) was slightly weaker than LAP. Waist-to-height ratio (WHtR) had the similar AUC (males: 0.717, females: 0.747) to conicity index (CI) (males: 0.734, females: 0.749), whereas the identification ability of a body shape index (ABSI) (males AUC: 0.700, females AUC: 0.717) was relatively weak. Compared with the diagnostic ability of a single indicator, the AUC of the male nomogram model was 0.876 (95%CI: 0.856–0.895) and the AUC of the female model was 0.877 (95%CI: 0.856–0.896). The identification ability had been significantly improved.

Conclusion

LAP and TyG index are effective indicators for identifying MetS among normal-weight adults in rural Xinjiang. Nomogram models including age, CI, LAP, and TyG index can significantly improve diagnostic ability.

Association between visceral fat and influenza infection in Japanese adults: A population-based cross-sectional study

Background

Several studies have reported that obesity is associated with influenza infection; however, the role of visceral fat remains unclear. The aim of this study was to investigate the association between visceral fat and influenza infection in community-dwelling Japanese adults.

Methods

A cross-sectional study was performed using data from an annual community-based health check-up conducted from May to June in 2019. In total, 1,040 Japanese adults aged 20–89 years were enrolled in this study. Influenza infection status was determined by participants’ responses to a self-administered questionnaire. The visceral fat area (VFA) was measured using a bioimpedance-type visceral fat meter. Participants were classified into four groups using the following cut-off points: VFA < 100 cm² was set as the reference category according to the Japanese criteria, 100 ≤ VFA < 150 cm², 150 ≤ VFA < 200 cm², and 200 cm² ≤ VFA. Logistic regression models were used to assess the association between VFA and influenza infection.

Results

In total, 119 participants had influenza infections in the past year. In the multivariate adjusted model, a higher VFA was significantly associated with increased influenza infection; the adjusted odds ratio for 200 cm² ≤ VFA was 5.03 [95% confidence interval (CI): 1.07–23.6], that for 150 ≤ VFA < 200 cm² was 1.97 (95% CI: 0.71–5.45), and that for 100 ≤ VFA < 150 cm² was 1.62 (95% CI: 0.84–3.12), compared with that for VFA < 100 cm² (p for trend = 0.049). These findings were confirmed in the same cohort the following year.

Conclusions

Our results suggest that visceral fat accumulation is associated with influenza infection. Large-scale prospective studies using diagnostic information for influenza infection are required to confirm this association.

The impact of the National Health Program on diabetes incidence among working-age men with prediabetes: A regression discontinuity analysis of a nation-wide database in Japan

AIM

This study aimed to investigate the impact of the National Health Program in Japan ("Specific Health Check-ups and Specific Health Guidance") on diabetes prevention among working-age men with prediabetes.

METHODS

This study used a regression discontinuity design, based on the program's criterion that the program starts at age 40 or older and that the intervention is provided only to prediabetic individuals with abdominal obesity, to assess the impact of the program on the diabetes incidence in a total of 49,848 men with prediabetes, aged 37-42 years.

RESULTS

The National Health Program in which interventions were provided for individuals aged 40 years or over with both prediabetes and abdominal obesity was associated with a decrease in diabetes incidence rate equivalent to 10.1 reduction/1000 person-years. The relative risk was 0.75. However, among those without abdominal obesity and not subjected to the intervention, there was no significant change in the diabetes incidence at age 40.

CONCLUSIONS

The National Health Program in Japan was associated with a decrease in the incidence of diabetes among working-age men with prediabetes and abdominal obesity and may have a meaningful impact among working-age men.

Association between Objectively Measured Sedentary Behaviour and Sleep Quality in Japanese Adults: A Population-Based Cross-Sectional Study

The association between sedentary behaviour and sleep quality (SQ) remains unclear, partly due to the limited methodology for assessing sedentary time and the influence of obesity. This study aimed to examine the association between objectively measured sedentary time and poor SQ, as well as the association of visceral fat accumulation. This cross-sectional study used health check-up data obtained from 721 Japanese adults. Sedentary time and physical activity were measured using an accelerometer for ≥7 days, with ≥10 measurement hours per day. Poor SQ was determined by a Pittsburgh Sleep Quality Index score of ≥ 6. Visceral fat was measured using the abdominal bioimpedance method. A logistic regression model was used to analyse the association between sedentary time and SQ. We found that higher sedentary time was associated with poorer SQ. This association remained significant after adjustment for several covariates, including visceral fat. Compared with the lowest tertile of sedentary time, the second and highest tertile had a significantly higher OR of poor SQ (Tertile 2: OR = 2.06 [95% CI 1.14,3,73]; Tertile 3: OR = 2.76 [95% CI 1.49, 5.11]). These results suggest that managing sedentary time itself might contribute to improving SQ.

Association of sedentary behaviour and physical activity with cardiometabolic health in Japanese adults

Although the Asian population exhibits excessive sedentary behaviour and has a high susceptibility to metabolic syndrome (MetS), the nature of these associations remains unclear. This study aimed to investigate the association of sedentary time with cardiometabolic health and examine the association of reallocating sedentary time to light physical activity (LPA) or moderate-vigorous physical activity (MVPA) on cardiometabolic health in Japanese adults. A cross-sectional study was performed using data obtained from 758 Japanese adults. We assessed sedentary time, LPA, and MVPA using an accelerometer. Linear and logistic regression models were used to analyse the association between sedentary time and cardiometabolic risk factors. An isotemporal substitution model was used to estimate the theoretical influence of reallocating sedentary time to LPA or MVPA. A longer sedentary time was associated with worse cardiometabolic health, including MetS. Reallocating 30 min of sedentary time to LPA was significantly associated with lower body mass index, visceral fat, insulin resistance, triglyceride, and MetS levels and increased muscle mass and HDL-C (all P < 0.05). Reallocating 30 min of sedentary time to MVPA was strongly associated with the aforementioned factors. These results demonstrate the potential beneficial effects of reallocating sedentary time to LPA and MVPA on cardiometabolic health of Asians.

Whole-exome sequencing analysis of a Japanese patient with hyperinsulinemia and liver dysfunction

Hyperinsulinemia is often observed in obese subjects because of insulin resistance, but it may occur in nonobese subjects with unknown etiology. A 72-year-old man was admitted to our hospital for the examination of hyperinsulinemia, reactive hypoglycemia, and liver dysfunction. The patient’s body mass index was 23.7 kg/m², but he had an elevated visceral fat area (125 cm²). His laboratory data showed mildly elevated liver enzymes, whereas plasma fasting glucose and serum insulin levels were 91 mg/dL and 52.3 μU/mL, respectively. In a 75-g oral glucose tolerance test, the serum insulin level reached the highest value of 1124 μU/mL at 180 minutes. There was no obvious etiology except for mild liver steatosis shown by liver biopsy. We suspected genetic abnormalities related to hyperinsulinemia. We performed whole-exome sequencing (WES) analyses and identified a heterozygous nonsense variant p.R924X in the insulin receptor (INSR) gene, a novel heterozygous missense variant p.V416M in the AKT1 gene, and a novel hemizygous missense variant p.R310Q in the PHKA2 gene, which is the causative gene of hepatic injury as glycogen storage disease type IX. It was speculated that the INSR gene variant, in addition to visceral fat accumulation, was the main cause of hyperinsulinemia and reactive hypoglycemia, and the remaining 2 variants were also partly responsible for hyperinsulinemia. WES analysis revealed candidate gene variants of hyperinsulinemia and hepatic-type glycogenosis. Thus, WES analysis may be a useful tool for clarifying the etiology when unexplained genetic pathophysiological conditions are suspected.

Weight Change Since Age 20 and the Risk of Cardiovascular Disease Mortality: A Prospective Cohort Study

Aim: Weight change could have many health outcomes. This study aimed to investigate the association between weight change and mortality risk due to total cardiovascular disease (CVD), ischemic heart disease (IHD), and stroke among Japanese.

Methods: We used Suita Study data from 4,746 people aged 30-79 years in this prospective cohort study. Weight change was defined as the difference between baseline weight and weight at age 20. We used Cox proportional hazards models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of total CVD, IHD, and stroke mortality for 1) participants with a weight change (＞10, 5 to 10, -5 to -10, and ＜-10 kg) compared to those with stable weight (-4.9 to 4.9 kg) and 2) participants who moved from one body mass index category (underweight, normal weight, or overweight) to another compared to those with normal weight at age 20 and baseline.

Results: Within a median follow-up period of 19.9 years, the numbers of total CVD, IHD, and stroke mortality were 268, 132, and 79, respectively. Weight loss of ＞10 kg was associated with the increased risk of total CVD mortality 2.07 (1.29, 3.32) and stroke mortality 3.02 (1.40, 6.52). Moving from normal weight at age 20 to underweight at baseline was associated with the increased risk of total CVD, IHD, and stroke mortality: 1.76 (1.12, 2.77), 2.10 (1.13, 3.92), and 2.25 (1.05, 4.83), respectively.

Conclusion: Weight loss, especially when moving from normal to underweight, was associated with the increased risk of CVD mortality.

Changes in Body Weight, Dysglycemia, and Dyslipidemia After Moderately Low-Carbohydrate Diet Education (LOCABO Challenge Program) Among Workers in Japan

PURPOSE

It is theorized that the prevalence of obesity has not decreased owing to poor adherence to implemented programs addressing metabolic syndrome, obesity, and diabetes in Japan. Therefore, we intended to evaluate the influence of a moderately low-carbohydrate diet on improving markers of metabolic syndrome among workers in Japan.

PATIENTS AND METHODS

Participants with metabolic syndrome or obesity were recruited based on the eligibility criteria for the Specific Health Guidance program and educated on a moderately low-carbohydrate diet between spring 2016 and fall 2018. The participants were then made to report their food intake and body weight once a week for the next 12 weeks and were counselled on maintaining a moderately low-carbohydrate diet. HbA1c levels, lipid profile, body weight, and sleep quality were evaluated. The normality of the data was evaluated using the Skewness/Kurtosis test. Each variable was compared before and after the intervention using the Wilcoxon signed-rank test. Further, a subgroup analysis of the data from the participants whose variables were abnormal at baseline was performed.

RESULTS

Among the 101 enrolled participants, a decrease in the median weight (from 82.5 to 79.7 kg, p<0.001, n=46), body mass index (from 27.3 to 26.9 kg/m², p<0.001, n=46), and apnea-hypopnea index (from 24.1 to 17.1, p<0.01, n=39) was observed. Subgroup analysis of participants with abnormal baseline values revealed changes in HbA1c (from 6.7% to 5.8%, p<0.001, n=34), total cholesterol (from 220 to 209 mg/dL, p<0.01, n=54), low-density lipoprotein cholesterol (from 133 to 120 mg/dL, p<0.001, n=31), high-density lipoprotein cholesterol (from 35 to 40 mg/dL, p<0.01, n=31), triglycerides (from 242 to 190 mg/dL, p<0.01, n=57), and deep sleep percentage (from 10.4% to 18.2%, p<0.05, n=7).

CONCLUSION

A moderately low-carbohydrate diet may be considered a potential intervention for improving the markers of metabolic syndrome, obesity, and diabetes.

Association of the National Health Guidance Intervention for Obesity and Cardiovascular Risks With Health Outcomes Among Japanese Men

IMPORTANCE

Obesity and cardiovascular risks have become major public health problems. However, evidence is limited as to whether population-level lifestyle interventions for obesity and cardiovascular risk factors are associated with improved population health outcomes.

OBJECTIVE

To investigate the association of the national health guidance intervention in Japan with population health outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used a regression discontinuity design that included men aged 40 to 74 years who participated in the national health screening program in Japan from April 2013 to March 2018.

EXPOSURES

Assignment to the national health guidance intervention (counseling on healthy lifestyle and appropriate clinical follow-up for individuals found to have waist circumference of 85 cm or greater with 1 or more cardiovascular risk factors during annual national health screening program).

MAIN OUTCOMES AND MEASURES

Changes in obesity status (body weight, body mass index, waist circumference), and cardiovascular risk factors (blood pressure, hemoglobin A1c level, and low-density lipoprotein cholesterol level) 1 to 4 years after screening.

RESULTS

Of 74 693 men (mean [SD] age, 52.1 [7.8] years; mean [SD] baseline waist circumference, 86.3 [9.0] cm), the assignment to the health guidance intervention was associated with lower weight (adjusted difference, -0.29 kg; 95% CI, -0.50 to -0.08; P = .005), body mass index (-0.10; 95% CI, -0.17 to -0.03; P = .008), and waist circumference (-0.34 cm; 95% CI, -0.59 to -0.04; P = .02) 1 year after screening. The observed association of the guidance assignment attenuated over time and was no longer significant by years 3 to 4. No evidence was found that the health guidance intervention was associated with changes in participants' systolic blood pressure, diastolic blood pressure, hemoglobin A1c level, or low-density lipoprotein cholesterol level in years 1 to 4.

CONCLUSIONS AND RELEVANCE

Among working-age men in Japan, the national health guidance intervention was not associated with clinically meaningful weight loss or other cardiovascular risk factor reduction. Further research is warranted to understand the specific design of lifestyle interventions that are effective in improving obesity and cardiovascular risk factors.

Beneficial effects of weekend catch-up sleep on metabolic syndrome in chronic short sleepers

OBJECTIVES

Short sleep duration has been known to be related to metabolic syndrome (MetS) . The aim of this study was to investigate the beneficial effects of weekend catch-up sleep (WCUS) on MetS in the Korean middle-aged population.

METHODS

For this cross-sectional study, 1,812 participants aged 35-60 years were selected from the 2016-2018 Korean National Health and Nutrition Examination Survey (mean age 46.94 years, 49% male). Short sleep duration was defined as <6hrs on weekdays, and participants were divided into two groups: WCUS group and no weekend catch-up sleep group. Multiple logistic regression was performed to determine the association between WCUS and MetS prevalence. The covariates included age, sex, education, income, occupation, smoking, alcohol consumption, and physical activity.

RESULTS

WCUS was significantly associated with lower MetS prevalence in the unadjusted model and in the model adjusted for socioeconomic and health behavior factors.

CONCLUSION

These results support the beneficial effects of WCUS on lowering the risk of MetS among middle-aged chronic short sleepers.

Metabolic Syndrome for Cardiovascular Disease Morbidity and Mortality Among General Japanese People: A Mini Review

Background

The importance of management of metabolic syndrome (MetS) for risk reduction of cardiovascular disease (CVD) has been recognized worldwide. Because of the comparatively unique characteristics of bodily figure/obesity and incident CVD in Japan, the relevance of MetS on CVD can be still discussed among Japanese people. The present study aimed to review briefly the relationship of MetS with CVD morbidity/mortality among general Japanese people.

Methods

Population-based prospective cohort studies evaluating the predictive value of MetS on CVD morbidity/mortality via a PubMed search up to 2019 were summarized.

Results

We identified two studies on morbidity that reported MetS to predict CVD morbidity. We identified three studies on mortality, and these studies showed an increased direction of hazard ratio (HR) of CVD mortality, while one study reported an insignificant prediction of MetS for CVD mortality. In the meta-analysis method, MetS significantly predicted CVD morbidity (HR=1.71 [95% confidence interval=1.34–2.18] in men and HR=1.89 [95% confidence interval=1.45–2.46] in women) as well as CVD mortality (HR=1.68 [95% confidence interval=1.37–2.06] in men and HR=1.73 [95% confidence interval=1.39–2.15] in women).

Conclusion

Among general Japanese people, MetS can be a positive predictor of CVD morbidity/mortality. Since the studies are limited, more research is needed to establish the findings.