Metabolically-healthy obesity and coronary artery calcification

Impact of Self-Rated Health on Progression to a Metabolically Unhealthy Phenotype in Metabolically Healthy Obese and Non-Obese Individuals

We examined the association between self-rated health (SRH), a subjective measure of an individual’s health status, and the incidence of metabolic abnormalities, as well as the effect of obesity on this association in metabolically healthy individuals. The cohort study included 85,377 metabolically healthy men and women who were followed annually or biennially for a median of 3.0 years (interquartile range, 1.9–4.1 years). A parametric proportional hazard model was used to assess hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between SRH and the incidence of metabolic abnormalities. During 258,689.03 person-years, 40,858 participants developed metabolic abnormalities. Poorer SRH was significantly associated with increased risk of developing any metabolic abnormality including hypertriglyceridemia, high homeostasis model assessment of insulin resistance (HOMA-IR), and fatty liver in a dose-dependent manner (p for trend <0.05). The association between SRH and progression to metabolically unhealthy status was much stronger in individuals with obesity than those without, especially in relation to any metabolic abnormality, fatty liver, and high C-reactive protein (all p for interaction by obesity <0.05). The multivariable-adjusted HR (95% CI) for any metabolic abnormality comparing the “poor or very poor” vs. the “very good” self-rated health category was 0.97 (0.90–1.05) among non-obese subjects, whereas the corresponding HR (95% CI) among obese subjects was 1.25 (1.02–1.52). Low SRH, as assessed by a single question, was independently associated with increased risk of progression to metabolically unhealthy status in metabolically healthy individuals, especially metabolically healthy individuals with obesity. SRH may help identify individuals at high risk for progression to metabolically unhealthy status.

Chronic hepatitis B virus infection and risk of dyslipidaemia: A cohort study

Hepatitis B virus (HBV) infection has been associated with a decreased prevalence of dyslipidaemia in cross-sectional studies, but cohort studies are limited. We investigated the longitudinal effects of chronic HBV infection on the development of dyslipidaemia. We performed a cohort study of 62 287 non-cirrhotic adult men and women free of dyslipidaemia who underwent serologic testing for hepatitis B surface antigen (HBsAg) and were followed annually or biennially for an average of 4.46 years. A parametric proportional hazard model was used to estimate the adjusted hazard ratio with 95% confidence interval (CI) for incident dyslipidaemia according to HBsAg seropositivity status. We identified 12 331 incident cases of hypercholesterolaemia during 278 004.4 person-years of follow-up (incident rate 44.4 per 1000 person-years). In models adjusted for age, sex, body mass index, year of screening exam, smoking status, alcohol intake, regular exercise and education level, the adjusted hazard ratios (95% CIs) for incident hypercholesterolaemia, high LDL cholesterolaemia; hypertriglyceridaemia, high non-HDL cholesterolaemia and low HDL cholesterolaemia comparing HBsAg-positive to HBsAg-negative participants was 0.71 (0.64-0.79), 0.83 (0.78-0.89), 0.61 (0.54-0.70), 0.69 (0.63-0.75) and 1.10 (0.98-1.24), respectively. An inverse association between HBsAg positivity and incident high apolipoprotein B were also identified, with a corresponding a hazard ratio of 0.63 (0.55-0.72). In a large cohort of apparently healthy Korean adults, HBsAg seropositivity was associated with lower risk of development of dyslipidaemia, suggesting a role of HBV infection in lipid metabolism.

Central role of obesity in endothelial cell dysfunction and cardiovascular risk

SUMMARY Atherosclerosis is the leading cause of mortality in the contemporary world. The critical role of the endothelial cells (EC) in vascular homeostasis, the metabolic changes that take place when the cell is activated, and the elements involved in these processes have been widely explored over the past years. Obesity and its impact, promoting a rise in blood levels of free fatty acids (FAs) are often associated with atherosclerosis and cardiovascular mortality. However, the mechanisms that promote cardiovascular structural changes and adaptive changes in the ECs, particularly in the context of obesity, are little known. Here, we reviewed studies that assessed the metabolic adaptations of healthy and dysfunctional ECs during exposure to FAs, as well as the epidemiological perspectives of cardiovascular structural changes in obesity. Finally, we explored the role of new agents – sphingolipids, dietary unsaturated fatty acids and sodium-glucose cotransporter-2 inhibitors (iSGLT2) – in atherosclerosis and their relationship with obesity.

Metabolically Healthy Obesity and High Carotid Intima-Media Thickness in Children and Adolescents: International Childhood Vascular Structure Evaluation Consortium

OBJECTIVE

It has been argued that metabolically healthy obesity (MHO) does not increase cardiovascular disease (CVD) risk. This study examines the association of MHO with carotid intima-media thickness (cIMT), a proxy of CVD risk, in children and adolescents.

RESEARCH DESIGN AND METHODS

Data were available for 3,497 children and adolescents aged 6-17 years from five population-based cross-sectional studies in Brazil, China, Greece, Italy, and Spain. Weight status categories (normal, overweight, and obese) were defined using BMI cutoffs from the International Obesity Task Force. Metabolic status (defined as "healthy" [no risk factors] or "unhealthy" [one or more risk factors]) was based on four CVD risk factors: elevated blood pressure, elevated triglyceride levels, reduced HDL cholesterol, and elevated fasting glucose. High cIMT was defined as cIMT ≥90th percentile for sex, age, and study population. Logistic regression model was used to examine the association of weight and metabolic status with high cIMT, with adjustment for sex, age, race/ethnicity, and study center.

RESULTS

In comparison with metabolically healthy normal weight, odds ratios (ORs) for high cIMT were 2.29 (95% CI 1.58-3.32) for metabolically healthy overweight and 3.91 (2.46-6.21) for MHO. ORs for high cIMT were 1.44 (1.03-2.02) for unhealthy normal weight, 3.49 (2.51-4.85) for unhealthy overweight, and 6.96 (5.05-9.61) for unhealthy obesity.

CONCLUSIONS

Among children and adolescents, cIMT was higher for both MHO and metabolically healthy overweight compared with metabolically healthy normal weight. Our findings reinforce the need for weight control in children and adolescents irrespective of their metabolic status.

Nonheavy Drinking and Worsening of Noninvasive Fibrosis Markers in Nonalcoholic Fatty Liver Disease: A Cohort Study

The effect of modest alcohol consumption on fibrosis progression in the general population with nonalcoholic fatty liver disease (NAFLD) remains unclear. We examined the association of nonheavy alcohol consumption with worsening of noninvasive fibrosis indices in a large-scale, low-risk population with NAFLD. A cohort study was performed in 58,927 Korean adults with NAFLD and low fibrosis scores who were followed for a median of 4.9 years. Non-, light, and moderate drinkers were defined as 0 g/day, 1-9.9 g/day, and 10-29.9 g/day (10-19.9 g/day for women), respectively. Progression from low to intermediate or high probability of advanced fibrosis was assessed using noninvasive indices including NAFLD fibrosis score (NFS) and Fibrosis-4 Index (FIB-4). A parametric proportional hazards model was used to estimate the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). During 347,925.4 person-years of follow-up, 5,630 subjects with low FIB-4 progressed to intermediate or high FIB-4. The multivariable-adjusted HRs (95% CI) for worsening of FIB-4 comparing light and moderate drinkers with nondrinkers were 1.06 (0.98-1.16) and 1.29 (1.18-1.40), respectively. Similarly, using NFS, corresponding HRs (95% CI) comparing light and moderate drinkers with nondrinkers were 1.09 (1.02-1.16) and 1.31 (1.23-1.40), respectively. Furthermore, the association of moderate drinkers with worsening of either FIB-4 or NFS remained significant after introducing alcohol use and confounders treated as time-varying covariates. Conclusion: In this large-scale cohort of young and middle-aged individuals with NAFLD, nonheavy alcohol consumption, especially moderate alcohol consumption, was significantly and independently associated with worsening of noninvasive markers of fibrosis, indicating that even moderate alcohol consumption might be harmful.

Alcohol and coronary artery calcification: an investigation using alcohol flushing as an instrumental variable

Background

We examined whether alcohol flushing could be used as an instrumental variable (IV) and investigated the effect of alcohol consumption on coronary calcification using alcohol flushing status as an IV.

Methods

We analysed cross-sectional data from 24 681 Korean adults (20 696 men and 3985 women) who had been administered a questionnaire assessing alcohol consumption and alcohol flushing, as well as a coronary artery calcium (CAC) measurement. The associations of alcohol flushing status with potential confounders and alcohol consumption were examined. We employed two-stage predictor substitution methodology for the IV analysis.

Results

The prevalence of alcohol flushing did not differ depending on gender, education, household income, cigarette smoking or physical activity. Balanced levels of confounders were observed between alcohol flushers and non-flushers. Alcohol flushing was closely related to alcohol consumption and levels of liver enzymes. In men, a doubling in alcohol consumption was associated with increased odds of coronary calcification in both the IV analysis [odds ratio (OR) of CAC scores of 1 or over = 1.11; 95% confidence interval (CI) = 1.03-1.20) and the multivariable regression analysis (OR = 1.04; 95% CI = 1.01-1.07). For cardiovascular risk factors, the IV analysis showed a positive association between alcohol consumption and blood pressure and high-density lipoprotein-cholesterol.

Conclusions

Alcohol flushing can be used as an IV in studies evaluating the health impact of alcohol consumption, especially in East Asian countries. Through such an analysis, we found that increased alcohol consumption was associated with an increased risk of subclinical coronary atherosclerosis.

Hepatitis B virus infection and development of chronic kidney disease: a cohort study

Background

The effect of chronic hepatitis B virus (HBV) infection on the risk of chronic kidney disease (CKD) is controversial. We examined the prospective association between hepatitis B surface antigen (HBsAg) serology status and incident CKD in a large cohort of men and women.

Methods

Cohort study of 299,913 adults free of CKD at baseline who underwent health screening exams between January 2002 and December 2016 in South Korea. Incident CKD was defined as the development of an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73m² and/or proteinuria.

Results

Over 1,673,701 person-years of follow-up, we observed 13,924 incident cases of CKD (3225 cases of eGFR < 60 ml/min/1.73m² and 11,072 cases of proteinuria). In fully adjusted models comparing positive to negative HBsAg participants, the hazard ratio (HR, 95% confidence interval) for incident CKD was 1.11 (1.03–1.21; P = 0.01). The corresponding HR for incident proteinuria and for eGFR < 60 ml/min/1.73m² were 1.23 (1.12–1.35; P <  0.001) and 0.89 (0.73–1.07; P = 0.21), respectively. The associations were similar across categories of liver enzyme levels at baseline.

Conclusion

In this large cohort, HBsAg positive serology was associated with higher risk of incident CKD, and we provide novel evidence that this association was due to a higher incidence of proteinuria in HBsAg positive participants. Our study adds to the growing body of evidence suggesting that chronic HBV infection may be a contributor to the increasing incidence of CKD.

Electronic supplementary material

The online version of this article (10.1186/s12882-018-1154-4) contains supplementary material, which is available to authorized users.

Distribution of metabolic/obese phenotypes and association with diabetes: 5 years' cohort based on 22,276 elderly

AIMS

To describe the distribution and changes of different metabolic/obese phenotypes among more than 22,000 male elderly in China, and also explore the association with diabetes incidence.

METHODS

A cohort study based on 22,276 male elderly was conducted in Beijing, from 2009 to 2013. Multiple Cox model was used to calculate the relative risk.

RESULTS

There were only 53.8% of total participants who kept the same phenotype for the 5 years. On the whole, participants with metabolically unhealthy phenotypes had higher relative risks (RRs) than those with metabolically healthy phenotypes. RRs for diabetes showed an increasing trend along with metabolic abnormalities (p < 0.001). However, no statistically significant difference was found across different obese status with the same number of metabolic abnormalities. Changes of metabolic/obese status also showed the same trend. Those who had kept metabolic unhealthy had the highest RRs for diabetes incidence, which was higher than those who kept obesity.

CONCLUSIONS

Both metabolically healthy obesity and metabolically unhealthy normal weight phenotypes had an increased risk for diabetes incidence, and metabolic abnormalities might have more influence on diabetes than obesity itself. Changes of metabolic/obese status also had an important impact on diabetes incidence.

Abdominal obesity phenotypes and incident diabetes over 12 years of follow-up: The Tehran Lipid and glucose study

AIMS

To investigate future diabetes in different abdominal obesity phenotypes during 12 years of follow-up.

METHODS

For this population-based cohort, 7982 adults without diabetes including 3533 men and 4449 women, aged ≥20 years were selected from the Tehran Lipid and Glucose Study. Abdominal obesity was defined according to the national cutoffs for waist circumference (WC). Metabolic health was defined as having ≤1 metabolic abnormality based on Joint Interim Statement (JIS) criteria other than WC. Participants were classified into 4 groups of abdominal obesity phenotypes: Metabolically healthy non-abdominal obese (MHNAO), metabolically healthy abdominal obese (MHAO), metabolically unhealthy non-abdominal Obese (MUNAO), and metabolically unhealthy abdominal obese (MUAO).

RESULTS

In total, 1018 cases of incident diabetes occurred. Compared to the MHNAO phenotype, based on multivariate Cox regression models, diabetes risk was increased in all unhealthy phenotypes except the MUNAO phenotype in men. Regarding the association of the MHAO phenotype with incident diabetes, borderline statistical significance in men [HR 1.5 (95% CI: 1.0-2.36), p-value: 0.07] and statistical significance in women [HR 1.68 (95% CI: 1.08-2.6)] were detected.

CONCLUSIONS

In addition to unhealthy phenotypes except the MUNAO phenotype in men, the MHAO phenotype is also associated with incident diabetes, highlighting the importance of preventive strategies in this subgroup of abdominally obese subjects.

Association between serum uric acid and arterial stiffness in a low-risk, middle-aged, large Korean population: A cross-sectional study

We investigated the association between serum uric acid (SUA) and brachial ankle pulse wave velocity (baPWV) in an apparently healthy population. We performed a cross-sectional study on middle-aged Koreans who completed a yearly health-screening program between January and December 2014. Subjects with coronary artery disease, diabetes, or hypertension were excluded. Linear regression analyses were used to study the relationship between SUA and baPWV. Multiple adjustments were made for variables based on clinical or statistical significance. Of 66,917 study participants (38,170 men and 28,747 women), the mean age was 39.4 ± 6.7 years and the average SUA level was 5.23 ± 1.4 mg/dL. SUA values were higher in men than in women (6.1 ± 1.2 mg/dL vs. 4.1 ± 0.8 mg/dL). SUA was linearly associated with baPWV in women and in men (P < .001, respectively). Multiple regression analyses remained significant for women with a positive association with baPWV across SUA quintiles in a dose-response manner (P < .001) while no longer for men with a J-shaped association between SUA quintiles and baPWV. When SUA modeled continuously, baPWV rose by 12.413 cm/s in women (P < .001) and by 6.588 cm/s in men (P < .001) for each 1 mg/dL increase of SUA. In a low-risk, middle-aged, large Korean population, higher SUA levels could have an unfavorable impact on arterial stiffness as measured by baPWV, and this association was stronger in women than in men.

Cigarette smoking and thyroid cancer risk: a cohort study

Background

We evaluated the association between smoking status and thyroid cancer risk and whether this association is mediated by body mass index (BMI) and thyroid-stimulating hormone (TSH).

Methods

We performed a cohort study of 96,855 Korean adults who were followed annually or biennially for a median of 5.9 years.

Results

During 511,052.9 person-years of follow-up, 1,250 participants developed thyroid cancer. In men, we observed a dose-dependent inverse association between current smoking, pack-years, and thyroid cancer. After adjustment for confounders, adjusted hazard ratios (95% confidence intervals) for thyroid cancer comparing current and former smokers to never smokers were 0.58 (0.45–0.75) and 0.93 (0.73–1.18), respectively. After further adjustment for BMI and TSH as potential mediators, this association was slightly attenuated, but remained significant. For women, current smokers tended to have a lower risk of thyroid cancer, but this association did not reach statistical significance.

Conclusions

In this cohort study, current smoking was associated with a decreased risk of incident thyroid cancer in men but not in women and this association was observed even after adjusting for TSH and BMI levels as potential mediators. Further mechanistic studies are needed to elucidate the possible effect of smoking on the pathogenesis of thyroid cancer development.

Health-related costs in a sample of premenopausal non-diabetic overweight or obese females in Antwerp region: a cost-of-illness analysis

Background

People with overweight or obesity are at increased risk for disease later in life which cause important health costs.

The aim of this study was to estimate the health status and the corresponding costs in a sample of females with overweight or obesity which were participating in a Randomized Controlled Trial (RCT) exploring the effect of lifestyle habits changes on ectopic adipose tissue.

Methods

Sixty-two non-diabetic premenopausal females without major comorbidities of overweight and obesity were recruited among patients visiting endocrinologists at the obesity clinic of the University Hospital of Antwerp and the University of Antwerp.

A RCT-embedded cost-of-illness approach with societal perspective, based on self-reported questionnaires and cost diaries (3 months recall) was applied to estimate the prevalence of different comorbidities and the related direct and indirect costs in this sample of overweight or obese females. The European Quality-of-Life-5D questionnaire was used to define the health state and the corresponding utility index of the participants.

Results

The average direct health costs and health utilities observed in this sample were comparable with the general Flemish female population. This may partially be explained by the strict inclusion criteria of the RCT (i.e. overweight or obesity without diabetes type 2 or cardiovascular diseases). However, 15% of the participants had five or more comorbidities resulting in higher average costs and lower average health utility as compared to the general population, only 3 participants were diagnozed with the metabolic syndrome. In this subsample productivity was low due to high average absenteeism, yielding important total costs for the society.

Conclusion

Secondary prevention to avoid health deterioration in overweight or obese females without major comorbidies is needed to contain health care costs.

Trial registration

ClinicalTrials.gov: NCT02831621, approval of the ethics committee of the University Hospital of Antwerp (number: 14/17/205 -ref: 7543075363).

Coronary Artery Calcium Score: the "Mammogram" of the Heart?

PURPOSE OF REVIEW

To discuss the classic analogy of "coronary artery calcium (CAC) as a mammogram of the heart", by evaluating the conceptual strengths, weaknesses, opportunities, and threats of a potential cardiovascular disease (CVD) screening strategy using CAC in apparently healthy adults.

RECENT FINDINGS

CAC is typically used for further CVD risk assessment. CAC is also currently being used as a screening test in specific subgroups of individuals, particularly in some Asian countries. Although this has yielded valuable insights on the determinants and pathophysiology of CVD, whether this approach results in improved clinical outcomes compared to other assessment and management approaches is currently unclear. Although CAC and mammograms share a number of characteristics, there are also important conceptual differences. The evidence supporting CAC, which is a robust CVD risk assessment tool, for CVD screening purposes is currently very limited, and further research is needed.

Coexistence of Colorectal Adenomas and Coronary Calcification in Asymptomatic Men and Women

GOALS

Because of shared risk factors between clinically manifest cardiovascular disease and colorectal cancer, we hypothesized the coexistence of subclinical atherosclerosis measured by coronary artery calcium (CAC) and colorectal adenoma (CRA) and that these 2 processes would also share common risk factors.

BACKGROUND

No study has directly compared the risk factors associated with subclinical coronary atherosclerosis and CRA.

STUDY

This was a cross-sectional study using multinomial logistic regression analysis of 4859 adults who participated in a health screening examination (2010 to 2011; analysis 2014 to 2015). CAC scores were categorized as 0, 1 to 100, or >100. Colonoscopy results were categorized as absent, low-risk, or high-risk CRA.

RESULTS

The prevalence of CAC>0, CAC 1 to 100 and >100 was 13.0%, 11.0%, and 2.0%, respectively. The prevalence of any CRA, low-risk CRA, and high-risk CRA was 15.1%, 13.0%, and 2.1%, respectively. The adjusted odds ratios (95% confidence interval) for CAC>0 comparing participants with low-risk and high-risk CRA with those without any CRA were 1.35 (1.06-1.71) and 2.09 (1.29-3.39), respectively. Similarly, the adjusted odds ratios (95% confidence interval) for any CRA comparing participants with CAC 1 to 100 and CAC>100 with those with no CAC were 1.26 (1.00-1.6) and 2.07 (1.31-3.26), respectively. Age, smoking, diabetes, and family history of CRC were significantly associated with both conditions.

CONCLUSIONS

We observed a graded association between CAC and CRA in apparently healthy individuals. The coexistence of both conditions further emphasizes the need for more evidence of comprehensive approaches to screening and the need to consider the impact of the high risk of coexisting disease in individuals with CAC or CRA, instead of piecemeal approaches restricted to the detection of each disease independently.

Urine Cotinine level with smoking history predicts a risk of coronary artery calcification

We investigated whether urine cotinine level, alone or combined with smoking status and cumulative smoking amount, could predict coronary calcium (CAC) score increase over time. The study population included 10,980 subjects. We analysed an association between CAC score increase over time and single or combined smoking-related factors. Urine cotinine level of ≥100 ng/mL, current or ex-smokers, and cumulative smoking amount of ≥1 pack-years (PY) showed significantly higher odds ratios (ORs) for CAC score increase over time. A combination of current smokers with >10 PY and urine cotinine level of ≥100 ng/mL showed the highest OR. Irrespective of smoking status and cumulative smoking amount, all combinations with urine cotinine of ≥100 ng/mL showed higher ORs than other combinations with urine cotinine level of <100 ng/mL. Urine cotinine levels can be useful to predict coronary artery calcification and encourage smokers to quit smoking.

Sitting time, physical activity and the risk of lower urinary tract symptoms: a cohort study

OBJECTIVES

To examine the association of sitting time and physical activity level with the incidence of lower urinary tract symptoms (LUTS) in a large sample of Korean men.

MATERIALS AND METHODS

A cohort study was performed in 69 795 Korean men, free of LUTS at baseline, who were followed up annually or biennially for a mean of 2.6 years. Physical activity level and sitting time were assessed using the validated Korean version of the International Physical Activity Questionnaire Short Form. LUTS were assessed using the International Prostate Symptom Score (IPSS) and clinically significant LUTS were defined as an IPSS score ≥8.

RESULTS

Over 175 810.4 person-years, 9 217 people developed significant LUTS (incidence rate, 39.0 per 1 000 person-years). In a multivariable-adjusted model, both low physical activity level and prolonged sitting time were independently associated with the incidence of LUTS. The hazard ratios (95% confidence intervals [CIs]) for incident LUTS comparing minimally active and health-enhancing physically active groups vs the inactive group were 0.94 (95% CI 0.89-0.99) and 0.93 (95% CI 0.87-0.99), respectively (P for trend 0.011). The hazard ratios (95% CIs) for LUTS comparing 5-9 and ≥10 h/day sitting time vs <5 h/day were 1.08 (95% CI 1.00-1.24) and 1.15 (95% CI 1.06-1.24), respectively (P for trend <0.001).

CONCLUSIONS

Prolonged sitting time and low physical activity levels were positively associated with the development of LUTS in a large sample of middle-aged Korean men. This result supports the importance of both reducing sitting time and promoting physical activity for preventing LUTS.

Diabetes mellitus and the incidence of hearing loss: a cohort study

Background

To evaluate the association between diabetes mellitus (DM) and the development of incident hearing loss.

Methods

Prospective cohort study was performed in 253 301 adults with normal hearing tests who participated in a regular health-screening exam between 2002 and 2014. The main exposure was the presence of DM at baseline, defined as a fasting serum glucose ≥ 126 mg/dL, a self-reported history of DM or current use of anti-diabetic medications. Pre-diabetes was defined as a fasting glucose 100-125 mg/dL and no history of DM or anti-diabetic medication use. Incident hearing loss was defined as a pure-tone average of thresholds at 0.5, 1.0 and 2.0 kHz > 25 dB in both right and left ears.

Results

During 1 285 704 person-years of follow-up (median follow-up of four years), 2817 participants developed incident hearing loss. The rate of hearing loss in participants with normal glucose levels, pre-diabetes and DM were 1.8, 3.1 and 9.2 per 1000 person-years, respectively ( P < 0.001). The multivariable-adjusted hazard ratios for incident hearing loss for participants with pre-diabetes and DM compared with those with normal glucose levels were 1.04 (95% confidence interval 0.95-1.14) and 1.36 (1.19-1.56), respectively. In spline regression analyses, the risk of incident hearing loss increased progressively with HbA1c levels above 5%.

Conclusions

In this large cohort study of young and middle-aged men and women, DM was associated with the development of bilateral hearing loss. DM patients have a moderately increased risk of future hearing loss.

Cultural primer for cardiometabolic health: health disparities, structural factors, community, pathways to improvement, and clinical applications

The quest to optimize cardiometabolic health has created great interest in nonmedical health variables in the population, community-based research and coordination, and addressing social, ethnic, and cultural barriers. All of these may be of equal or even greater importance than classical health care delivery in achieving individual well-being. One dominant issue is health disparity - causes, methods of reduction, and community versus other levels of solutions. This communication summarizes some major views regarding social structures, followed by amplification and synthesis of central ideas in the literature. The role of community involvement, tools, and partnerships is also presented in this Primer. Recent views of how these approaches could be incorporated into cardiometabolic initiatives and strategies follow, with implications for research. Two examples comparing selected aspects of community leverage and interventions in relation to individual approaches to health care equity are examined in depth: overall performance in reducing cardiovascular risk and mortality, and the recent National Diabetes Prevention Program, both touching upon healthy diets and adherence. Finally, the potential that precision medicine offers, and possible effects on disparities are also discussed.

The association between serum uric acid and asymptomatic intracranial arterial stenosis in middle-aged Koreans

BACKGROUND AND AIMS

Intracranial arterial stenosis (ICAS) is one of the most common causes of stroke, especially in Asians. Hyperuricemia has been associated with an increased risk of comorbidities such as metabolic syndrome or cardiovascular diseases. However, there are few studies focusing on the association between serum uric acid (SUA) levels and asymptomatic ICAS. The aim of this study was to explore the association between SUA and the prevalence of ICAS in middle-aged Korean health screening examinees.

METHODS AND RESULTS

A cross-sectional study was performed on 9417 males and 7755 females who underwent a comprehensive health examination including transcranial Doppler (TCD) ultrasonography. The association of SUA and ICAS was analyzed using multivariate logistic regression. The prevalence of ICAS among the total examinee population was 3.55%. In females, the multivariate-adjusted odds ratio for ICAS was 1.52 (confidence interval 1.13-2.04) in the 3rd quartile of SUA and 1.45 (1.05-2.00) in the highest quartile, compared to the reference (P for trend 0.008). This trend was evident in all clinically relevant subgroups evaluated, including women with low inflammation status. SUA was not significantly associated with the prevalence of ICAS among males. In a sensitivity analysis, the multivariate-adjusted odds ratio of middle cerebral artery stenosis in females was 1.60 (1.09-2.37) in the highest quartile compared to the reference (P for trend 0.023).

CONCLUSIONS

Higher SUA level was associated with increased risk of ICAS among middle-aged females but not males. A further cohort study is warranted to elucidate the effect of SUA on asymptomatic ICAS.

[Insulinoresistancy in Man: from mechanisms to nutritional interference]

Obesity is presently regarded as the "the first non-infectious epidemic outbreak" in the history of Humanity. It is a multifactorial pathology, that contributes to the emergence of insulinoresistancy. Some obese individuals display an obesity qualified as metabolically sound, i.e., non-associated with metabolical anomalies. The present paper reviews the different possible mechanisms responsible for insulin-resistancy.

Relative muscle mass and the risk of incident type 2 diabetes: A cohort study

Aims

The association between relative muscle mass (RMM) and incidence of type 2 diabetes (T2DM) is largely unknown. We examined whether RMM predicted development of T2DM in an apparently young healthy population.

Methods

This cohort study was comprised of 113,913 men and 89,854 women, free of T2DM at baseline, who underwent a health checkup examination and were followed-up annually or biennially for an average of 2.9 years. We used skeletal muscle mass index (SMI) as an indicator of RMM. SMI (%) [total skeletal muscle mass (kg)/body weight (kg)×100] was estimated using a bioelectrical impedance analyzer. The study outcome was incident T2DM, defined as fasting serum glucose ≥126 mg/dL, HbA1C ≥6.5%, or use of medication for T2DM.

Results

During 589,098.8 person-years of follow-up, 4,264 individuals developed T2DM (incidence rate, 7.2 per 1000 person-years). Median age (range) at baseline was 39.1 years (18.1–87.1). RMM was negatively associated with incidence of T2DM in a dose-response manner. The multivariate-adjusted hazard ratios (95% CIs) for incident T2DM comparing quartiles 3, 2 and 1 of RMM to the highest quartile were 1.32 (1.14–1.52), 1.63 (1.42–1.86), and 2.21 (1.94–2.51), respectively, for males and 1.18 (0.88–1.58), 1.46 (1.11–1.91), and 1.96 (01.51–2.53) for females (P for trend <0.001; 0.011). This association was stronger in younger or premenopausal subjects.

Conclusions

RMM was negatively associated with development of T2DM in a large sample of young and middle-aged Korean adults. Further research is required to determine whether preservation of muscle mass through intervention affects the risk of T2DM.

Long-term Effects of high-doSe pitavaStatin on Diabetogenicity in comparison with atorvastatin in patients with Metabolic syndrome (LESS-DM): study protocol for a randomized controlled trial

Background

The diabetogenic action of statins remains a concern, particularly in patients at high risk for diabetes receiving intensive statin therapy. Despite the risk of diabetes with statin use being considered a potential class effect, recent studies have suggested that pitavastatin exerts neutral or favorable effects on diabetogenicity. However, no randomized trial has compared the long-term effects of pitavastatin with those of other statins on glycemic control in populations at high risk for diabetes. Hence, we aim to assess the long-term effects of pitavastatin in comparison with atorvastatin on glucose metabolism in patients with metabolic syndrome (MetS).

Methods/design

The Long-term Effects of high-doSe pitavaStatin on Diabetogenicity in comparison with atorvastatin in patients with Metabolic syndrome (LESS-DM) trial is a prospective, randomized, open-label, active control clinical trial of patients with MetS. We plan to randomize 500 patients with MetS (1:1) to receive high-dose pitavastatin (4 mg) or atorvastatin (20 mg) daily for 24 months. The primary endpoint will be the change in hemoglobin A1c after statin treatment. Secondary endpoints will include the following: (1) changes in biochemical markers, including insulin, C-peptide, homeostasis model assessment of insulin resistance and insulin secretion, and adiponectin; (2) changes in imaging parameters, including carotid elasticity metrics and indices of cardiac function; and (3) the incidence of clinical events, including new-onset diabetes and cardiovascular disease.

Discussion

In this trial, we will explore whether pitavastatin 4 mg does not disturb glucose metabolism in patients with MetS. It will also provide mechanistic information on statin type-dependent diabetogenic effects and surrogate data regarding vascular and cardiac changes achieved by intensive statin therapy.

Trial registration

ClinicalTrials.gov, NCT02940366. Registered on 19 October 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2229-4) contains supplementary material, which is available to authorized users.

The "Jolly Fat" Effect in Middle-Aged Korean Women

BACKGROUND

It has been hypothesized that depression and obesity are bi-directionally associated, and when overweight people appear to show a lower risk of depression, this supports the "Jolly Fat" hypothesis. The aim of this study was to examine the "Jolly Fat" hypothesis in middle-aged women in Korea, by different perceived stress levels.

METHODS

We performed a cross-sectional study of 44 to 56 aged Korean women (n = 2201) who underwent a health check-up program at the healthcare centers of Kangbuk Samsung Hospital (Seoul and Suwon centers) in Korea. General and abdominal obesity were defined as body mass index ≥25 kg/m² and waist circumference ≥85 cm, respectively. Depressive symptoms were measured by a Korean version of the Center for Epidemiologic Studies-Depression scale. The association between obesity and depressive symptoms was investigated by using multiple logistic regression analyses by different levels of perceived stress, with adjustment for potential confounding factors.

RESULTS

The prevalence of general and abdominal obesity and depressive symptoms were 23.7%, 21.4%, and 16.5%, respectively. Women with general obesity were less likely to have depressive symptoms (odds ratio [OR]: 0.50; 95% confidence interval [CI]: 0.25-1.00; p-value: 0.049) in the low-stress group. We also found that women with abdominal obesity had a 60% decrease in the odds of having depressive symptoms (OR: 0.40; 95% CI: 0.18-0.87; p-value: 0.02) in the low-stress group. No significant association was found in the high-stress group.

CONCLUSIONS

These findings indicate that the relationship between obesity and depressive symptoms in the Korean middle-aged women supports the "Jolly Fat" hypothesis. Further, our results underscore the role of stress as an important potential mediator exerting effects on the association between obesity and depressive symptoms.

The Definition and Prevalence of Obesity and Metabolic Syndrome

Increase in prevalence of obesity has become a worldwide major health problem in adults, as well as among children and adolescents. Furthermore, total adiposity and truncal subcutaneous fat accumulation during adolescence are positively and independently associated with atherosclerosis at adult ages. Centrally accumulation of body fat is associated with insulin resistance, whereas distribution of body fat in a peripheral pattern is metabolically less important. Obesity is associated with a large decrease in life expectancy. The effect of extreme obesity on mortality is greater among younger than older adults. In this respect, obesity is also associated with increased risk of several cancer types. However, up to 30% of obese patients are metabolically healthy with insulin sensitivity similar to healthy normal weight individuals, lower visceral fat content, and lower intima media thickness of the carotid artery than the majority of metabolically "unhealthy" obese patients.Abdominal obesity is the most frequently observed component of metabolic syndrome. The metabolic syndrome; clustering of abdominal obesity, dyslipidemia, hyperglycemia and hypertension, is a major public health challenge. The average prevalence of metabolic syndrome is 31%, and is associated with a two-fold increase in the risk of coronary heart disease, cerebrovascular disease, and a 1.5-fold increase in the risk of all-cause mortality.

Hepatitis B and C virus infection and diabetes mellitus: A cohort study

The role of hepatitis virus infection in glucose homeostasis is uncertain. We examined the associations between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the development of diabetes in a cohort (N = 439,708) of asymptomatic participants in health screening examinations. In cross-sectional analyses, the multivariable-adjusted odds ratio for prevalent diabetes comparing hepatitis B surface antigen (HBsAg) (+) to HBsAg (−) participants was 1.17 (95% CI 1.06–1.31; P = 0.003). The corresponding odds ratio comparing hepatitis C antibodies (HCV Ab) (+) to HCV Ab (−) participants was 1.43 (95% CI 1.01–2.02, P = 0.043). In prospective analyses, the multivariable-adjusted hazard ratio for incident diabetes comparing HBsAg (+) to HbsAg (−) participants was 1.23 (95% CI 1.08–1.41; P = 0.007). The number of incident cases of diabetes among HCV Ab (+) participants (10 cases) was too small to reliably estimate the prospective association between HCV infection and diabetes. In this large population at low risk of diabetes, HBV and HCV infections were associated with diabetes prevalence and HBV infection with the risk of incident diabetes. Our studies add evidence suggesting that diabetes is an additional metabolic complication of HBV and HCV infection.

Metabolically healthy obesity: a friend or foe?

Obesity is associated with a reduced life expectancy, largely because obese individuals are at an increased risk of type 2 diabetes, cardiovascular disease, and several types of cancer. Much interest has recently focused on the concept of "all obesity is not created equally." Obese individuals without the metabolic abnormalities that commonly accompany excess adiposity, a condition known as metabolically healthy obesity (MHO), account for a substantial proportion of the obese adult population. Numerous possible mechanisms underlying MHO have been suggested, including adipose tissue distribution and inflammation. However, the prognostic value of MHO is controversial and considerably challenging. The lack of a standard definition for metabolic health and obesity as well as the dynamic properties of MHO may have contributed to these inconsistent results. This review aimed to present several current issues regarding MHO including its definition, epidemiology, natural course, suggested mechanisms, and clinical implications in the context of patient prognosis.

Influence of the definition of "metabolically healthy obesity" on the progression of coronary artery calcification

OBJECTIVES

Debates whether metabolically healthy obesity (MHO) increases the cardiovascular risk might be due to the metabolic instability of MHO or the absence of a perfect definition of MHO. Therefore, we aimed to investigate the influence of the MHO phenotype on the coronary artery calcium score (CACS) progression according to definition of MHO.

METHODS

We analyzed a retrospective cohort with a CACS of 0 at baseline and available serial CACS measurements taken ≥ 12 months apart (n = 1,218). Obesity was defined as BMI ≥ 25 kg/m2, and MHO was defined as obesity accompanied by ≤ 1 (MHO class I) or 0 (MHO class II) components of metabolic syndrome (MetS).

RESULTS

During a median follow-up of 45 months, 32.2% of MHO class I and 10.2% of MHO class II subjects developed MetS. Compared to non-obese/metabolically healthy subjects (reference group), hazard ratios (HR) for development of MetS were 2.174 (95% confidence interval [CI]: 1.513-3.124) and 1.166 (95% CI: 0.434-3.129) for MHO class I and II subjects, respectively. The MHO class I subjects showed a significantly increased risk of CACS progression as compared to the reference group (HR: 1.653; 95% CI: 1.144-2.390), whereas MHO class II subjects did not (HR: 1.195; 95% CI: 0.514-2.778). Among subjects with MHO class I, no significant CACS progression was observed in the subjects who maintained metabolic health during follow-up (HR: 1.448; 95% CI: 0.921-2.278).

CONCLUSIONS

The risks of metabolic deterioration and CACS progression were significant in subjects with MHO class I, but not in those with MHO class II.

Healthy obesity and risk of accelerated functional decline and disability

BACKGROUND/OBJECTIVES

Some obese adults have a normal metabolic profile and are considered 'healthy', but whether they experience faster ageing than healthy normal-weight adults is unknown. We compared decline in physical function, worsening of bodily pain and likelihood of future mobility limitation and disability between these groups.

SUBJECTS/METHODS

This was a population-based observational study using repeated measures over 2 decades (Whitehall II cohort data). Normal-weight (body mass index (BMI) 18.5-24.9 kg m-2), overweight (25.0-29.9 kg m-2) and obese (⩾30.0 kg m-2) adults were considered metabolically healthy if they had 0 or 1 of 5 risk factors (hypertension, low high-density lipoprotein cholesterol, high triacylglycerol, high blood glucose and insulin resistance) in 1991/1994. Decline in physical function and worsening of bodily pain based on change in Short Form Health Survey items using eight repeated measures over 18.8 years (1991/1994-2012/2013) were compared between metabolic-BMI groups using linear mixed models. Odds of mobility limitation based on objective walking speed (slowest tertile) and of disability based on limitations in ⩾1 of 6 basic activities of daily living, each using three repeated measures over 8.3 years (2002/2004-2012/2013), were compared using logistic mixed models.

RESULTS

In multivariable-adjusted mixed models on up to 6635 adults (initial mean age 50 years; 70% male), healthy normal-weight adults experienced a decline in physical function of -3.68 (95% CI=-4.19, -3.16) score units per decade; healthy obese adults showed an additional -3.48 (-4.88, -2.08) units decline. Healthy normal-weight adults experienced a -0.49 (-1.11, 0.12) score unit worsening of bodily pain per decade; healthy obese adults had an additional -2.23 (-3.78, -0.69) units worsening. Healthy obesity versus healthy normal-weight conferred 3.39 (2.29, 5.02) times higher odds of mobility limitation and 3.75 (1.94, 7.24) times higher odds of disability.

CONCLUSIONS

Our results suggest that obesity, even if metabolically healthy, accelerates age-related declines in functional ability and poses a threat to independence in older age.

Relationship Between γ-Glutamyltransferase Levels and Left Ventricular Diastolic Dysfunction

BACKGROUND

The goal of this study was to examine the association of serum γ-glutamyltransferase (GGT) levels with left ventricular (LV) diastolic dysfunction and LV hypertrophy.Methods and Results:A cross-sectional study of 79,459 Korean men and women who underwent an echocardiography as part of a comprehensive health examination between March 2011 and December 2014. The presence of LV diastolic dysfunction and LV hypertrophy was determined using echocardiography. Of the subjects, 5,447 had LV diastolic dysfunction and 2,070 had LV hypertrophy. Both LV diastolic dysfunction and LV hypertrophy were associated with higher levels of serum GGT. Multivariable-adjusted odds ratios (95% confidence interval) for LV diastolic dysfunction comparing serum GGT quartiles 2-4 with quartile 1 were 1.25 (1.08-1.44), 1.65 (1.43-1.91) and 2.23 (1.92-2.58), respectively (P for trend <0.001). Multivariable-adjusted odds ratios (95% CI) for LV hypertrophy comparing serum GGT quartiles 2-4 with quartile 1 were 1.13 (0.94-1.36), 1.14 (0.93-1.40) and 1.33 (1.07-1.65), respectively (P for trend 0.01). These associations of serum GGT levels with LV diastolic dysfunction and LV hypertrophy were modified by age (P for interaction <0.05).

CONCLUSIONS

This study demonstrated a positive association between serum GGT levels and LV diastolic dysfunction and LV hypertrophy in a large cohort of middle-aged men and women independent of potential confounders.

Sleep duration and quality in relation to chronic kidney disease and glomerular hyperfiltration in healthy men and women

Background

It is unclear whether sleep duration and quality are associated with chronic kidney disease (CKD) and glomerular hyperfiltration. The aim of this study was to examine the association of sleep duration and quality with CKD and glomerular hyperfiltration in young and middle-aged adults.

Methods

We conducted a cross-sectional study of men and women who underwent a health checkup examination, including assessment of sleep duration and quality (n = 241,607). Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73 m², and glomerular hyperfiltration was defined as eGFR above the age-/sex-specific 95^th percentile.

Results

In a multinomial logistic regression analysis adjusting for relevant confounders, the adjusted prevalence ratios for CKD (95% confidence interval) comparing sleep durations of ≤ 5, 6, 8, and 9 hours with 7 hours were 1.22 (0.95–1.55), 0.93 (0.75–1.14), 0.97 (0.75–1.26), and 1.56 (1.06–2.30) in men and 0.98 (0.68–1.43), 1.03 (0.72–1.46), 1.39 (0.97–2.00), and 1.31 (0.78–2.22) in women, respectively. The corresponding prevalence ratios (95% confidence interval) for glomerular hyperfiltration were 1.00 (0.93–1.08), 0.97 (0.91–1.03), 1.03 (0.94–1.13), and 1.39 (1.13–1.72) in men and 1.04 (0.95–1.14), 0.96 (0.90–1.04), 1.11 (1.02–1.20), and 1.28 (1.14–1.45) in women, respectively. Poor subjective sleep quality was associated with glomerular hyperfiltration in men and women.

Conclusion

In this large study of young and middle-aged adults, we found that long sleep duration was associated with CKD and glomerular hyperfiltration. Additionally, poor subjective sleep quality was associated with increased prevalence of glomerular hyperfiltration, suggesting the importance of adequate quantity and quality of sleep for kidney function.

Development of Nephrolithiasis in Asymptomatic Hyperuricemia: A Cohort Study

BACKGROUND

Although the association between gout and nephrolithiasis is well known, the relationship between asymptomatic hyperuricemia and the development of nephrolithiasis is largely unknown.

STUDY DESIGN

Cohort study.

SETTING & PARTICIPANTS

239,331 Korean adults who underwent a health checkup examination during January 2002 to December 2014 and were followed up annually or biennially through December 2014.

PREDICTOR

Baseline serum uric acid levels of participants.

OUTCOME

The development of nephrolithiasis during follow-up.

MEASUREMENTS

Nephrolithiasis is determined based on ultrasonographic findings. A parametric Cox model was used to estimate the adjusted HRs of nephrolithiasis according to serum uric acid level.

RESULTS

During 1,184,653.8 person-years of follow-up, 18,777 participants developed nephrolithiasis (incidence rate, 1.6/100 person-years). Elevated uric acid level was significantly associated with increased risk for nephrolithiasis in a dose-response manner (P for trend < 0.001) in men. This dose-response association was not observed in women. In male participants, multivariable-adjusted HRs for incident nephrolithiasis comparing uric acid levels of 6.0 to 6.9, 7.0 to 7.9, 8.0 to 8.9, 9.0 to 9.9, and ≥10.0mg/dL with uric acid levels < 6.0mg/dL were 1.06 (95% CI, 1.02-1.11), 1.11 (95% CI, 1.05-1.16), 1.21 (95% CI, 1.13-1.29), 1.31 (95% CI, 1.17-1.46), and 1.72 (95% CI, 1.44-2.06), respectively. This association was observed in all clinically relevant subgroups and persisted even after adjustment for homeostasis model assessment of insulin resistance and high-sensitivity C-reactive protein level.

LIMITATIONS

Dietary information and computed tomographic diagnosis of nephrolithiasis were unavailable.

CONCLUSIONS

In this large cohort study, increased serum uric acid level was modestly and independently associated with increased risk for the development of nephrolithiasis in a dose-response manner in apparently healthy men.

Cardiometabolic Risk Factors Among 1.3 Million Adults With Overweight or Obesity, but Not Diabetes, in 10 Geographically Diverse Regions of the United States, 2012-2013

INTRODUCTION

Various phenotypes of overweight and obesity pose various health risks. The objective of this study was to determine the prevalence of 4 commonly measured cardiometabolic risk factors (CRFs) among adults with overweight or obesity, but not diabetes, at the time of the study.

METHODS

We analyzed data for 1,294,174 adults (aged ≥20 y) who were members of one of 4 integrated health systems. Each cohort member had a body mass index in 2012 or 2013 that indicated overweight or obesity. We determined the presence of 4 CRFs within 1 year of the first BMI measurement: elevated blood pressure (systolic ≥130 mm Hg or diastolic >85 mm Hg or ICD-9-CM [International Classification of Diseases, Ninth Revision, Clinical Modification] diagnosis code 401.0-405.9); elevated triglycerides (≥150 mg/dL or ICD-9-CM 272.1); low high-density lipoprotein cholesterol (<40 mg/dL for men or <50 mg/dL for women or ICD-9-CM 272.5); and prediabetes (fasting glucose 100-125 mg/dL or HbA_1c 5.7%-6.4% or ICD-9-CM 790.2x). We tested the risk of having 1 or more CRFs after adjusting for obesity class and demographic characteristics with multivariable logistic regression.

RESULTS

Among participants with overweight (52.5% of the sample), 18.6% had none of the 4 CRFs. Among the 47.5% of participants with obesity, 9.6% had none; among participants with morbid obesity, 5.8% had none. Age was strongly associated with CRFs in multivariable analysis.

CONCLUSION

Almost 10% of participants with obesity had no CRFs. Overweight or obesity increases cardiometabolic risk, but the number and type of CRFs varied substantially by age, even among participants with morbid obesity.

Hepatitis B infection is associated with an increased incidence of thrombocytopenia in healthy adults without cirrhosis

The association between HBV infection and incident thrombocytopenia among subjects without cirrhosis or splenomegaly is unknown. Therefore, we sought to elucidate the association between HBV infection and the development of thrombocytopenia in a large cohort of apparently healthy men and women. A cohort study was performed in 122 200 participants without liver cirrhosis or splenomegaly who underwent comprehensive health examinations and were followed until December 2014. HBV infection was defined by the presence of hepatitis B surface antigen (HBsAg) at baseline. Thrombocytopenia was defined as a platelet count <150 000/μL. Cox proportional hazard models were used to estimate adjusted hazard ratios with 95% confidence intervals (CIs) for incident thrombocytopenia. HBsAg was positive in 4857 of 122 200 subjects (4.0%) at baseline. During 883 983 person-years of follow-up, 2037 incident cases of thrombocytopenia were identified (incident rate 2.3 per 1000 person-years). HBsAg-positive subjects had a higher incidence of thrombocytopenia than did healthy controls (11.2 vs 1.9 per 1000 person-years, respectively). The multivariate-adjusted hazard ratio (95% CI) for incident thrombocytopenia comparing HBsAg-positive to HBsAg-negative subjects was 5.71 (5.10-6.38). Strong associations between HBsAg positivity and thrombocytopenia were consistently observed across prespecified subgroups. In this large cohort study of an apparently healthy population, HBsAg positivity was strongly and independently associated with incident thrombocytopenia, indicating that mechanisms of thrombocytopenia other than portal hypertension may exist in healthy HBV carriers.

Hepatitis B virus infection and decreased risk of nonalcoholic fatty liver disease: A cohort study

The presence of an association between chronic hepatitis B virus (HBV) infection and fatty liver is controversial. We examined the association between HBV infection and the development of nonalcoholic fatty liver disease (NAFLD). We conducted a cohort study of 83,339 participants without NAFLD at baseline who underwent serologic testing for hepatitis B surface antigen (HBsAg) between 2002 and 2006 and were followed annually or biennially until December 2014. NAFLD was defined as the presence of ultrasonographic fatty liver in the absence of excessive alcohol use or other identifiable causes. We used a parametric Cox model to estimate adjusted hazard ratios with 95% confidence intervals of incident NAFLD. During 484,736.1 person-years of follow-up, 20,200 incident NAFLD cases were identified. In models adjusted for age, sex, year of visit, smoking status, alcohol intake, regular exercise, education level, and body mass index, the adjusted hazard ratio (95% confidence interval) for incident NAFLD comparing HBsAg-positive to HBsAg-negative participants was 0.83 (0.73-0.94). After introducing HBV infection and confounders (including homeostasis model assessment of insulin resistance and metabolic factors) as time-dependent exposures, the association between HBV infection and decreased risk of incident NAFLD was attenuated but persisted. These associations were consistently observed across clinically relevant, prespecified subgroups.

CONCLUSION

In this large cohort of apparently healthy Korean adults, HBsAg seropositivity was associated with lower risk of developing NAFLD, indicating a possible effect of HBV infection on the pathogenesis of NAFLD development. (Hepatology 2017;65:828-835).

Post-challenge insulin concentration is useful for differentiating between coronary artery disease and cardiac syndrome X in subjects without known diabetes mellitus

BACKGROUND

Cardiac syndrome X (CSX) is characterized by angina pectoris but with patent coronary arteries. Our previous study demonstrated that subjects with CSX had a higher fasting insulin-resistance (IR) than the controls. However, few studies have investigated the degree of IR, including oral glucose tolerance test (OGTT)-derived indices and profiles of metabolic abnormalities between CSX and coronary artery disease (CAD).

METHODS

Ninety-two CSX and 145 CAD subjects without known diabetes mellitus (DM) underwent coronary angiogram (CAG) for angina pectoris and also agreed to receive OGTT and glycated hemoglobin (HbA_1C) evaluations for screening abnormal glucose regulation and IR.

RESULTS

CAD group had more subjects with metabolically unhealthy obesity (52.4 vs. 31.5%, p < 0.001) than the CSX group. The CAD group had higher OGTT 2 h glucose and insulin (both p < 0.005) while fasting glucose, insulin and HOMA-IR were similar to those of CSX subjects. In the binary regression analysis, OGTT 2 h insulin and being metabolic unhealthy were significantly different between the CAD and CSX groups, but there were no significant differences in Matsuda index, fasting glucose, insulin, HOMA-IR, or HbA_1C.

CONCLUSIONS

Post challenge OGTT 2 h insulin and being metabolic unhealthy were useful parameters in differentiating between CAD and CSX in subjects without known DM but suffered from angina pectoris and underwent CAG. Different degrees of IR and metabolic abnormalities might be implicated in the pathogenesis of micro vs. macro vascular coronary diseases. Trial registration NCT01198730 at https://clinicaltrials.gov, Registered Sep. 8, 2010.

Insulin resistance increases loss of antibody to hepatitis B surface antigen in nondiabetic healthy adults

The aim of this study was to evaluate the impact of insulin resistance on the persistence of a protective level of anti-HBs (hepatitis B surface antigen) in a nondiabetic general population. A cohort study was designed comprising of 38 473 Korean men and women with anti-HBs at concentrations ≥10 mIU/mL, who underwent a health examination. Insulin resistance was assessed with a homoeostasis model assessment of insulin resistance (HOMA-IR). A decline in anti-HBs to <10 mIU/L during the follow-up was considered to be a loss of protective anti-HBs. Cox-proportional hazard models were used to estimate the adjusted hazard ratios and 95% confidence intervals for anti-HBs loss across quintiles of HOMA-IR and insulin. We identified 20 826 incidents of loss of anti-HBs antibody during 180 522 person-years of follow-up (incident rate 11.5 per 100 person-years). Increasing HOMA-IR was positively associated with incident loss of anti-HBs. The multivariable-adjusted hazard ratios (95% confidence intervals) for incident loss of anti-HBs comparing quintiles 2-5 vs quintile 1 of HOMA-IR were 1.09 (1.04-1.14), 1.14 (1.09-1.19), 1.14 (1.09-1.19) and 1.21 (1.16-1.27), respectively. These associations were stronger in younger individuals under the age of 35 than in people 35 years of age or older (P for interaction = 0.004). The association was also more evident in subjects with higher titres (≥100 mIU/mL) of anti-HBs than in those with low titres (P for interaction < 0.001). Insulin resistance was associated with an increased risk for loss of vaccine-acquired anti-HBs in a large sample of a nondiabetic, general population, indicating a possible role of insulin resistance in vaccine-induced immunity.

Dietary sodium and potassium intake in relation to non-alcoholic fatty liver disease

A few epidemiological data are available assessing the associations of intakes of sodium (Na) and potassium (K) with non-alcoholic fatty liver disease (NAFLD). We aimed to examine the associations of dietary intake of Na and K with the prevalence of ultrasound-diagnosed NAFLD. We performed a cross-sectional study of 100 177 participants (46 596 men and 53 581 women) who underwent a health screening examination and completed a FFQ at the Kangbuk Samsung Hospital Total Healthcare Centers, South Korea, between 2011 and 2013. NAFLD was defined by ultrasonographic detection of fatty liver in the absence of excessive alcohol intake or other known causes of liver disease. The proportion of NAFLD was 35·6 % for men and 9·8 % for women. Increasing prevalence of NAFLD was observed with increasing Na intake. The multivariable-adjusted prevalence ratios (PR) of NAFLD comparing the highest with the lowest quintile of energy-adjusted Na intake were 1·25 (95 % CI 1·18, 1·32; P trend<0·001) in men and 1·32 (95 % CI 1·18, 1·47; P trend <0·001) in women. However, when we additionally adjusted for body fat percentage, the association became attenuated; the corresponding PR of NAFLD were 1·15 (95 % CI 1·09, 1·21) in men and 1·06 (95 % CI 0·95, 1·17) in women. No inverse association was observed for energy-adjusted K intake. Our findings suggest that higher Na intake is associated with a greater prevalence of NAFLD in young and middle-aged asymptomatic adults, which might be partly mediated by adiposity.

Gallstones and the Risk of Gallbladder Cancer Mortality: A Cohort Study

OBJECTIVES

Despite epidemiologic data, definitive evidence for the role of gallstones as a cause for gallbladder cancer is lacking. The goal of this study was to evaluate the association between gallstones, determined by ultrasound, and the risk of gallbladder cancer mortality in a large study of Korean men and women. In addition, the association between gallstones and cholecystectomy, and risk of hepatobiliary cancer mortality was investigated.

METHODS

A cohort study was performed for 396,720 South Korean men and women who underwent a health checkup from 2002 to 2012. Hazard ratios for mortality outcomes were estimated using Cox-proportional hazards regression analysis. Vital status and cause of death assignment were based on linkage to the National Death Index of death certificate records.

RESULTS

From a total of 2,158,906.2 person-years of follow-up (median follow-up of 5.4 years), we identified 224 deaths from hepatobiliary cancer, comprising 174 cases of liver/intrahepatic bile ducts cancer, 20 cases of gallbladder cancer, and 30 cases of biliary tract cancer. Gallstones were significantly associated with increased risk of hepatobiliary cancer mortality, especially liver/intrahepatic biliary cancer, and gallbladder cancer mortality. The multivariable-adjusted hazard ratios (95% confidence intervals) for hepatobiliary cancer, liver/intrahepatic biliary cancer, and gallbladder cancer mortality comparing subjects having gallstones with those without gallstone disease were 2.74 (1.83-4.10), 2.34 (1.45-3.77), and 7.35 (2.60-20.8), respectively. Cholecystectomy was not significantly associated with hepatobiliary cancer mortality.

CONCLUSIONS

In this large cohort study, gallstones were associated with increased risk of hepatobiliary cancer mortality, especially liver/intrahepatic cancer, and gallbladder cancer mortality independent of potential confounders. Future studies with longer follow-up periods that include data on incident cancer cases should provide a more comprehensive view of the role of gallstones in cancer development.

"Metabolically healthy" obesity: Prevalence, clinical features and association with myocardial ischaemia

OBJECTIVE

To evaluate the prevalence of the "metabolically healthy" (MH) or "metabolically unhealthy" (MU) obesity phenotypes and their association with cardiorespiratory fitness and inducible myocardial ischaemia.

METHODS

Individuals without known coronary artery disease undergoing myocardial perfusion single-photon emission computed tomography (MPS) were studied. Those without dyslipidemia, hypertension, or diabetes were considered MH, and when ≥1 of these was present, MU status was considered present. Summed stress and difference perfusion scores (SSS and SDS, respectively) were calculated; a SDS >1 defined ischaemic MPS.

RESULTS

MH patients were 35.0% of the nonobese population and 23.5% of the obese (p<0.001). The prevalence of ischaemia was not significantly different between MH patients with obesity or MH patients without obesity (10.9% vs 9.1%, p=0.3), except for patients with body mass index ≥40kg/m² (21.9%). MH obese patients were less frequently able to exercise and had lower exercise capacity than the nonobese patients.

CONCLUSIONS

The prevalence of myocardial ischaemia was not significantly different between MH obese or nonobese individuals, supporting the concept of the "metabolically healthy obesity". However, there are other factors involved, such as the ability to exercise, that influence the risk of myocardial ischaemia, limiting the "safety" of that obesity phenotype.

Metabolically healthy obesity is associated with an increased risk of diabetes independently of nonalcoholic fatty liver disease

OBJECTIVE

This study examined whether the metabolically healthy obesity (MHO) phenotype was associated with an increased risk of diabetes in a large cohort of metabolically healthy individuals and whether that association differed by presence of nonalcoholic fatty liver disease (NAFLD).

METHODS

The cohort consisted of 74,509 Korean adults who were metabolically healthy at baseline, defined as not having any metabolic syndrome component except large waist circumference and having homeostasis model assessment of insulin resistance <2.5. NAFLD was defined as hepatic steatosis on ultrasonography in the absence of excessive alcohol use or any other identifiable cause.

RESULTS

Over 304,852.6 person-years of follow-up, 472 participants developed diabetes (incidence density, 1.5 per 1,000 person-years). The multivariable-adjusted hazard ratios (95% confidence intervals) for incident diabetes in subjects with overweight and obesity compared with subjects with normal weight were 1.29 (1.00-2.16) and 1.57 (1.14-2.16), respectively, for subjects without NAFLD and 1.90 (0.95-3.80) and 2.57 (1.32-5.02), respectively, for those with NAFLD (P for interaction =0.57).

CONCLUSIONS

In this metabolically healthy population, individuals with overweight and obesity exhibited an increased incidence of diabetes, regardless of the presence of NAFLD. This finding suggests that the obese phenotype per se, independent of the presence of NAFLD, can increase the development of diabetes.