Metabolic Health Is More Important than Obesity in the Development of Nonalcoholic Fatty Liver Disease: A 4-Year Retrospective Study

Prevalence and factors associated with unhealthy metabolic status according to body mass index: analysis of a national nutritional survey

INTRODUCTION

Although obesity substantially influences public health owing to related comorbidities, it has been discovered that the incidence of such issues is not directly related to obesity but to the patient's unhealthy metabolic status (MUS) independent of the body mass index (BMI).

OBJECTIVES

To describe the prevalence of UMS overall and according to BMI and determine the factors associated with it.

METHODS

A cross-sectional analytical study was used based on the analysis of secondary databases called the Life Stage Nutritional Surveillance Survey (VIANEV). Participants were selected in two stages, finally obtaining 885 participants. UMS was defined based on the criteria of the Adult Treatment Panel III used to define metabolic status in a set of 5 parameters, if the subject presented two or more alterations it was considered UMS. Six groups were formed according to BMI: metabolically healthy, average weight (MHNW) and unhealthy (MUNW), metabolically healthy, overweight (MHOW) and unhealthy (MUOW), metabolically healthy, obese (MHO) and unhealthy (MUO).).

RESULTS

The total prevalence of UMS was 73.11%, with MUNW, MUOW, and MUO being 47.90%, 80.34%, and 96.44%, respectively. Only 5.31% did not present any metabolic alteration. The multivariable analysis found variations globally according to sex, age, marital status, geographical region, smoking habit, and altitude.

CONCLUSIONS

A high prevalence of UMS was observed in Peru, indicating that BMI alone is not a sufficient indicator of metabolic status. These findings suggest that strategies should be prioritized to address the growing problem of UMS, considering the particularities of each subpopulation and using a multifaceted approach that addresses modifiable and non-modifiable risk factors.

MAFLD: an ideal framework for understanding disease phenotype in individuals of normal weight

The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) is significant, impacting almost one-third of the global population. MAFLD constitutes a primary cause of end-stage liver disease, liver cancer and the need for liver transplantation. Moreover, it has a strong association with increased mortality rates due to various extrahepatic complications, notably cardiometabolic diseases. While MAFLD is typically correlated with obesity, not all individuals with obesity develop the disease and a significant percentage of MAFLD occurs in patients without obesity, termed lean MAFLD. The clinical features, progression and underlying physiological mechanisms of patients with lean MAFLD remain inadequately characterized. The present review aims to provide a comprehensive summary of current knowledge on lean MAFLD and offer a perspective on defining MAFLD in individuals with normal weight. Key to this process is the concept of metabolic health and flexibility, which links states of dysmetabolism to the development of lean MAFLD. This perspective offers a more nuanced understanding of MAFLD and its underlying mechanisms and highlights the importance of considering the broader metabolic context in which the disease occurs. It also bridges the knowledge gap and offers insights that can inform clinical practice.

Insulin Resistance, Non-Alcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus: Clinical and Experimental Perspective

It has been generally accepted that insulin resistance (IR) and reduced insulin secretory capacity are the basic pathogenesis of type 2 diabetes mellitus (T2DM). In addition to genetic factors, the persistence of systemic inflammation caused by obesity and the associated threat of lipotoxicity increase the risk of T2DM. In particular, the main cause of IR is obesity and subjects with T2DM have a higher body mass index (BMI) than normal subjects according to recent studies. The prevalence of T2DM with IR has increased with increasing BMI during the past three decades. According to recent studies, homeostatic model assessment of IR was increased compared to that of the 1990s. Rising prevalence of obesity in Korea have contributed to the development of IR, non-alcoholic fatty liver disease and T2DM and cutting this vicious cycle is important. My colleagues and I have investigated this pathogenic mechanism on this theme through clinical and experimental studies over 20 years and herein, I would like to summarize some of our studies with deep gratitude for receiving the prestigious 2023 Sulwon Award.

Increased metabolic variability in Korean patients with new onset bipolar disorder: a nationwide cohort study

Introduction

The aim of this study was to determine associations between changes of metabolic parameters and the development of BD using nationally representative data.

Methods

We used health examination data provided by the South Korean National Health Insurance System (NHIS) (n = 8,326,953). The variability of each metabolic parameter including weight circumference, blood pressure, fasting blood glucose, high-density lipoprotein cholesterol, and triglyceride levels was caculated using variability independent of mean (VIM) indices. The presence of metabolic syndrome was associated with new onset BD. Each metabolic parameter with high variability was associated with a higher risk of new onset BD compared to those with low variability after adjusting for age, sex, smoking, alcohol drinking, regular exercise, income status, baseline diabetes, hypertension, and dyslipidemia.

Results

As the number of highly variable metabolic parameters increased, the risk for new onset depression also increased even after covariates adjustment. The associations between new onset BD and metabolic variability were greater in populations with age > 50 years. In addition, these associations remained significant after adjusting for the presence of depression prior to diagnoses of BD.

Discussion

Our results suggest possibility of metabolic variability as an independent environmental risk factor for BD even after adjusting for the presence of metabolic syndrome.

Increased risk of incident atrial fibrillation in young adults with mental disorders: A nationwide population-based study

BACKGROUND

Mental disorders and cardiovascular diseases are closely related. However, a paucity of information on the risk of incident atrial fibrillation (AF) in patients with mental disorders exists.

OBJECTIVE

We aimed to assess the association between mental disorders and the risk of AF, particularly in young adults.

METHODS

Using the Korean National Health Insurance Database between 2009 and 2012, we identified adults aged 20-39 years without a history of AF and who have been diagnosed with mental disorders. Mental disorders were defined as having one of the following diagnoses: depression, insomnia, anxiety disorder, bipolar disorder, or schizophrenia. The primary outcome was new-onset AF during follow-up.

RESULTS

A total of 6,576,582 subjects (mean age 30.9 ± 5.0 years; 3,919,339 [59.6%] men) were included. Among the total population, 10% had mental disorders. During the follow-up period, 8932 incident AF events occurred. Patients with mental disorders showed a higher AF incidence than did those without (25.4 per 100,000 person-years vs 17.7 per 100,000 person-years). After multivariable adjustment, mental disorders were associated with a significantly higher risk of AF (adjusted hazard ratio 1.526; 95% confidence interval 1.436-1.621). Patients with bipolar disorder or schizophrenia had a 2-fold higher risk of AF and those with depression, insomnia, and anxiety disorder had a 1.5- to 1.7-fold higher risk of AF than did those without mental disorders.

CONCLUSION

Young adults diagnosed with mental disorders have a higher risk of incident AF. Awareness for AF in high-risk populations should thus be considered.

Association between Sarcopenic Obesity Status and Nonalcoholic Fatty Liver Disease and Fibrosis

Background/Aims

There are no data regarding the association between sarcopenic obesity status and nonalcoholic fatty liver disease (NAFLD) and NAFLD-associated liver fibrosis. Therefore, we aimed to investigate the relationship between sarcopenic obesity status (sarcopenia only, obesity only, and sarcopenic obesity) and NAFLD and liver fibrosis in Korean adults.

Methods

In total, 2,191 subjects completed a health checkup program, including abdominal ultrasonography and FibroScan. Subjects were classified into the following four categories: optimal body composition (nonobese and nonsarcopenic), sarcopenia only (nonobese), obesity only (nonsarcopenic), and sarcopenic obesity. Sarcopenic obesity was stratified by the skeletal muscle mass index and body fat using bioelectrical impedance analysis. NAFLD was diagnosed by ultrasonography, and liver fibrosis was assessed using transient elastography in subjects with NAFLD.

Results

The prevalence of NAFLD and liver fibrosis significantly increased according to the sarcopenic obesity status. In the logistic regression analysis, after adjusting for multiple risk factors, the odds ratio (OR) for the risk of NAFLD was largest in the sarcopenic obesity group (OR, 3.68; 95% confidence interval [CI], 2.94 to 4.60), followed by the obesity only (OR, 2.25; 95% CI, 1.67 to 3.03) and sarcopenia only (OR, 1.92; 95% CI, 1.30 to 2.84) groups, when compared with the optimal group. Additionally, liver fibrosis was independently associated with sarcopenic obesity status (OR 4.69, 95% CI 1.95 to 11.29; OR 4.17, 95% CI 1.56 to 11.17; OR 3.80, 95% CI 0.86 to 16.75, respectively).

Conclusions

These results demonstrated that sarcopenic obesity was independently associated with NAFLD and liver fibrosis and increased the risk of NAFLD and liver fibrosis more than obesity or sarcopenia alone.

Lean non-alcoholic fatty liver disease (Lean-NAFLD) and the development of metabolic syndrome: a retrospective study

Lean NAFLD is a special phenotypic closely correlated with metabolic syndrome (MS). The aim of this study is to investigate the MS development and the gender differences in lean NAFLD population. Participants were divided into 4 groups by BMI and NAFLD status. Descriptive analysis was performed to characterize baseline information. A total of 18,395 subjects were participated, and 1524 incident cases of MS were documented. Then, Kaplan–Meier curves were used to present the MS outcomes in different groups, and the NAFLD was found to be a riskier factor than obesity for MS. Subgroup analysis showed significantly higher MS incidence in female than male among lean NAFLD group, which is different from other groups. Although with higher prevalence in male, lean NAFLD seems to be a more harmful phenotype for females according to the TG, ALT and GGT levels. The logistic regressive analysis was performed to show the impact of NAFLD status and BMI changes on MS risk. Lean non-NAFLD subjects merely developed to NAFLD with no BMI status changes exhibited highest MS risk (ORs = 1.879, 95% CI 1.610–2.292) than that with both BMI increase and NAFLD development (ORs = 1.669, 95% CI 1.325–2.104). It also suggests the metabolic specificity of this population.

The impact of metabolic health on non-alcoholic fatty liver disease (NAFLD). A single center experience

BACKGROUND

The role of patients' metabolic clinical and biochemical profile in NAFLD has not been extensively explored.

AIMS

The aim of the study was to assess the role of metabolic health in NAFLD patients and to examine liver disease progression in these populations.

METHODS

The medical charts of 569 patients diagnosed with fatty liver were thoroughly reviewed; 344 patients were excluded because of other chronic liver diseases. Metabolically healthy people were defined as those who met none of the following criteria: blood pressure ≥ 130/85 mmHg or under hypertension treatment, fasting glucose ≥ 100 mg/dl or under diabetes treatment, serum triglycerides > 150 mg/dl, high density lipoprotein-cholesterol <40/50 mg/dl for men/women. Study participants were followed-up over a median period of 22 months.

RESULTS

The present observational case-control study included 225 NAFLD patients; 14 (6.2%) were metabolically healthy. Metabolically healthy participants were younger (p = 0.006), had lower age at diagnosis (p = 0.002), lower levels of γ-GT (p = 0.013), fasting glucose (p <0.001) and triglycerides (p <0.001) and higher HDL-cholesterol (p = 0.005) compared to metabolically non-healthy. By the last follow up assessment, 8 metabolically healthy patients had developed dyslipidemia; 1 patient (14.4%) had presented liver disease progression compared to 8 patients (10.5%) from the unhealthy group (p = 0.567). In multivariate analysis, diabetes mellitus (p = 0.017) and hemoglobin levels (p = 0.009) were the sole independent predictors of disease progression. No significant difference was observed in liver disease progression-free survival rates among the two patient groups (p = 0.503).

CONCLUSIONS

Metabolically healthy NAFLD patients presented with a favorable biochemical profile; however, they were diagnosed with NAFLD at a younger age and the liver disease progression risk was similar to that of metabolically unhealthy patients. These findings suggest that metabolically healthy NAFLD may not constitute a benign condition and patients could potentially be at increased risk of metabolic syndrome and liver disease progression.

Increased metabolic variability is associated with newly diagnosed depression: A nationwide cohort study

BACKGROUND

The effect of dynamic changes in metabolic parameters over time on the development of depression has yet to be examined. In this study, we aimed to determine the association between the variability of metabolic parameters and the development of depression using nationally representative data.

METHODS

We used health examination data provided by the South Korean National Health Insurance System (NHIS) and included those who underwent the examination ≥ 3 times within five years of enrollment, without a previous history of depression (n = 9,058,424). The variability of each metabolic parameter including weight circumference, blood pressure, fasting blood glucose, high-density lipoprotein cholesterol, and triglyceride levels was estimated using variability independent of mean (VIM) indices. High variability was defined as the highest quartile (Q4) of variability.

RESULTS

Each metabolic parameter with high variability was associated with a higher risk of newly diagnosed depression compared to those with low variability, after adjusting for age, sex, smoking, alcohol drinking, regular exercise, income status, baseline diabetes, hypertension, and dyslipidemia. As the number of highly variable metabolic parameters increased, the risk for newly diagnosed depression increased even after adjusting for the aforementioned covariates (hazard ratio (HR) = 1.4, 95% confidence interval (CI): 1.3 - 1.4 in those with five highly variable parameters compared to those with no highly variable parameter).

LIMITATIONS

relatively short observation period; no systematic measure of depression severity.

CONCLUSIONS

Our results suggest that the variability of metabolic parameters is an independent risk factor for depression.

Metabolically healthy obesity and risk of non-alcoholic fatty liver disease severity independent of visceral fat

BACKGROUND AND AIM

Obesity and metabolic conditions may be related to non-alcoholic fatty liver disease (NAFLD). The study assesses the risk of NAFLD according to obesity and metabolic health status in a community-based population.

METHODS

A total of 1651 subjects were recruited from the community. Individuals were categorized into four groups according to obesity status (defined as a body mass index ≥ 25 kg/m² ) and metabolically healthy status: metabolically healthy nonobesity (MHNO), metabolically healthy obesity (MHO), metabolically unhealthy nonobesity (MUHNO), and metabolically unhealthy obesity (MUHO). NAFLD was diagnosed based on a semiquantitative ultrasonography measurement. Visceral fat was assessed through bioelectrical impedance analysis and is shown by tertile (T1, T2, and T3). A proportional odds model was used to assess the cumulative risk of NAFLD.

RESULTS

The NAFLD prevalence was 26.7%, 62.8%, 47.0%, and 76.7% in subjects with MHNO, MHO, MUHNO, and MUHO, respectively (P < 0.0001). After adjustment for age, sex, exercise habits, alcohol consumption, cigarette smoking, and visceral fat, the odds ratios for more severe NAFLD were 2.44 (95% confidence interval [CI]: 1.64-3.65), 2.75 (95% CI: 1.91-3.94), and 7.41 (95% CI: 4.94-11.12) in the MHO, MUHNO, and MUHO groups, respectively, compared with the MHNO group. In addition, the odds ratios for more severe NAFLD significantly increased with the increase in visceral fat level (T2 vs T1: 3.83, 95% CI: 2.65-5.53; T3 vs T1: 9.17, 95% CI: 5.33-15.79).

CONCLUSION

Both obesity and metabolically unhealthy status were associated with a higher risk of NAFLD independent of visceral fat level.

Epidemiology of nonalcoholic fatty liver disease in non-obese populations: Meta-analytic assessment of its prevalence, genetic, metabolic, and histological profiles

OBJECTIVE

As a subgroup of nonalcoholic fatty liver disease (NAFLD), patients with non-obese NAFLD may also have an increased risk of adverse hepatic and metabolic outcomes. We aimed to estimate the prevalence and incidence of non-obese NAFLD and to describe its clinical characteristics in this systematic review and meta-analysis.

METHODS

We performed a systematic search of 1235 citations published up to Mar 2020. Meta-analyses, stratified analyses and meta-regression were all performed.

RESULTS

Of the 46 studies included, 28 cross-sectional and longitudinal studies of 155 846 non-obese participants reported a pooled NAFLD prevalence of 14.5% (95% confidence interval [CI] 12.3%-17.1%). A multivariate meta-regression analysis showed the trend that the prevalence varied by their geographical location. Further stratified analyses showed that NAFLD was relatively prevalent among people aged ≥45 years (16.2%; 95% CI 10.8-23.4) and those in South America (25.7%; 95% CI 24.4-27.0). The PNPLA3 rs738409 gene polymorphism was more frequently observed in non-obese NAFLD than in both obese NAFLD and non-obese controls, while the metabolic profiles of non-obese NAFLD were less severe than those of the obese NAFLD group. Patients with non-obese NAFLD had 4.81-fold and 5.43-fold higher risk of diabetes mellitus and metabolic syndrome, respectively, than the non-obese controls.

CONCLUSIONS

Non-obese NAFLD is common, particularly in South America and among people aged ≥45 years. Metabolic diseases and PNPLA3 rs738409 gene polymorphism are more frequent in the non-obese NAFLD group than in non-obese controls.

Impact of obesity and metabolic health status in the development of non-alcoholic fatty liver disease (NAFLD): A United Kingdom population-based cohort study using the health improvement network (THIN)

BACKGROUND

With the obesity epidemic reaching crisis levels, there has been attention around those who may be resilient to the effects of obesity, termed metabolically healthy obesity (MHO), who initially present without associated metabolic abnormalities. Few longitudinal studies have explored the relationship between MHO and non-alcoholic fatty liver disease (NAFLD), which we address using over 4 million primary care patient records.

METHODS

A retrospective population-based longitudinal cohort was conducted using The Health Improvement Network (THIN) database incorporating adults with no history of NAFLD or alcohol excess at baseline. Individuals were classified according to BMI category and metabolic abnormalities (diabetes, hypertension and dyslipidaemia). Diagnosis of NAFLD during follow-up was the primary outcome measure. NAFLD was identified by Read codes.

RESULTS

During a median follow-up period of 4.7 years, 12,867 (0.3%) incident cases of NAFLD were recorded in the cohort of 4,121,049 individuals. Compared to individuals with normal weight and no metabolic abnormalities, equivalent individuals who were overweight, or obese were at significantly greater risk of incident NAFLD (Adjusted HR 3.32 (95%CI 2.98-3.49), and 6.92 (6.40-7.48, respectively). Metabolic risk factors further increased risk, including in those with normal weight and 1 (2.27, 1.97-2.61) or = < 2 (2.39, 1.99-2.87) metabolic abnormalities.

CONCLUSIONS

MHO individuals are at greater risk of developing NAFLD compared to those with normal weight. This finding supports that the MHO phenotype is a temporary state, and weight must be considered a risk factor even before other risk factors develop. Being normal weight with metabolic abnormalities was also associated with risk of NAFLD.

The expression signatures in liver and adipose tissue from obese Göttingen Minipigs reveal a predisposition for healthy fat accumulation

BACKGROUND

Model animals are valuable resources for dissecting basic aspects of the regulation of obesity and metabolism. The translatability of results relies on understanding comparative aspects of molecular pathophysiology. Several studies have shown that despite the presence of overt obesity and dyslipidemia in the pig key human pathological hepatic findings such as hepatocellular ballooning and abundant steatosis are lacking in the model.

OBJECTIVES

The aim of this study was to elucidate why these histopathological characteristics did not occur in a high fat, fructose and cholesterol (FFC) diet-induced obese Göttingen Minipig model.

METHODS

High-throughput expression profiling of more than 90 metabolically relevant genes was performed in liver, subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) of male minipigs diet fed: standard chow (SD, n = 7); FFC diet (n = 14); FFC diet in streptozotocin-induced diabetic pigs (FFCDIA, n = 8). Moreover, histopathological assessment of SAT and VAT was performed.

RESULTS

12, 4 and 1 genes were highly significantly differentially expressed in liver, SAT and VAT when comparing the FFC and SD groups whereas the corresponding numbers were 15, 2, and 1 when comparing the FFCDIA and SD groups. Although the minipigs in both FFC groups developed sever obesity and dyslipidemia, the insulin-signaling pathways were not affected. Notably, four genes involved in lipid acquisition and removal, were highly deregulated in the liver: PPARG, LPL, CD36 and FABP4. These genes have been reported to play a major role in promoting hepatic steatosis in rodents and humans. Since very little macrophage-associated pro-inflammatory response was detected in the adipose tissues the expansion appears to have no adverse impact on adipose tissue metabolism.

CONCLUSION

The study shows that morbidly obese Göttingen Minipigs are protected against many of the metabolic and hepatic abnormalities associated with obesity due to a remarkable ability to expand the adipose compartments to accommodate excess calories.

Understanding the association of polycystic ovary syndrome and non-alcoholic fatty liver disease

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among reproductive-age women. Patients with non-alcoholic fatty liver disease (NAFLD) often suffer from metabolic syndrome, atherosclerosis, ischemic heart disease, and extrahepatic tumors, conferring a lower survival than the general population; therefore it is crucial to study the association between NAFLD and PCOS since it remains poorly understood. Insulin resistance (IR) plays a central role in the pathogenesis of NAFLD and PCOS; also, hyperandrogenism enhances IR in these patients. IR, present in the NAFLD-PCOS association could decrease the hepatic production of sex hormone-binding globulin through a possible regulation mediated by hepatocyte nuclear factor 4 alpha. On the other hand, apoptotic processes initiated by androgens actively contribute to the progression of NAFLD. Considering the association between the two conditions, the screening of women with PCOS for the presence of NAFLD appears reasonable. The pathophysiological mechanisms of PCOS-NAFLD association and the initial approach will be reviewed here.

Ultrasound-Diagnosed Nonalcoholic Fatty Liver Disease Independently Predicts a Higher Risk of Developing Diabetes Mellitus in Nonoverweight Individuals

RATIONALE AND OBJECTIVES

This study was aimed to evaluate the independent value of ultrasound-diagnosed nonalcoholic fatty liver disease (us-NAFLD), as a surrogate imaging marker of the pathologic entity of NAFLD, in predicting incident diabetes mellitus (DM) in nonoverweight individuals.

MATERIALS AND METHODS

A total of 10,064 participants who had a body mass index <23 kg/m² were included in this retrospective cohort study. us-NAFLD was diagnosed using abdominal ultrasound. All participants were divided into subgroups according to the presence or absence of us-NAFLD and metabolic syndrome (MS).

RESULTS

Over a mean follow-up of 6.0 years, 125 participants (1.2%) developed DM. The incidence rates of DM were 1.0% in participants without us-NAFLD, 6.2% in participants with us-NAFLD, 1.1% in participants without MS, and 13.2% in participants with MS. The adjusted hazard ratios for incident DM were 2.52 (95% confidence interval:1.58-4.03) for us-NAFLD and 2.64 (95% confidence interval:1.54-4.54) for MS.

CONCLUSION

This study demonstrates that us-NAFLD has an independent value in predicting incident DM in non-overweight individuals.

Longitudinal analysis of risk of non-alcoholic fatty liver disease in adulthood

BACKGROUND & AIMS

We aimed to determine how childhood body mass index and metabolic health, along with the change in body mass index between childhood and adulthood, determine the risk of adult non-alcoholic fatty liver disease.

METHODS

Data from 2020 participants aged 3-18 years at baseline, followed up 31 years later, were examined to assess the utility of four childhood metabolic phenotypes (Metabolic Groups I: normal body mass index, no metabolic disturbances; II: normal body mass index, one or more metabolic disturbances; III: overweight/obese, no metabolic disturbances; IV: overweight/obese, one or more metabolic disturbances) and four life-course adiposity phenotypes (Adiposity Group 1: normal child and adult body mass index; 2, high child, normal adult body mass index; 3, normal child body mass index, high adult body mass index; 4, high child and adult body mass index) in predicting adult non-alcoholic fatty liver disease.

RESULTS

The risk for adult non-alcoholic fatty liver disease was similar across all four groups after adjustment for age, sex, lifestyle factors and adult body mass index. Risk of adult non-alcoholic fatty liver disease was not increased among individuals overweight/obese in childhood but non-obese in adulthood. In contrast, overweight or obese adults, irrespective of their youth body mass index status, had ~eight-fold to 10-fold increased risk (P < 0.001).

CONCLUSIONS

Childhood overweight/obesity, not metabolic health, is associated with increased risk for adult non-alcoholic fatty liver disease. However, the increased risk associated with childhood overweight/obesity can be largely removed by obtaining a normal body mass index by adulthood.

Weight change and mortality and cardiovascular outcomes in patients with new-onset diabetes mellitus: a nationwide cohort study

BACKGROUND

Because weight control is a cornerstone of diabetes management, it is important to understand the relationship of weight change to risk of cardiovascular disease (CVD) among patients with type 2 diabetes mellitus (DM). We aimed to investigate whether changes in weight early after diagnosis influence the incidence of CVD and all-cause mortality in patients with type 2 DM.

METHODS

Using nationally representative data from the Korean National Health Insurance System, 173,246 subjects with new-onset DM who underwent health examinations during 2007-2012 were included. Weight was measured at the time of diabetes diagnosis and 2 years later. Weight change over 2 years was divided into five categories of 5% weight change, from weight loss ≥ - 10% to weight gain ≥ 10%.

RESULTS

There were 3113 deaths (1.8%), 2060 cases of stroke (1.2%), and 1767 myocardial infarctions (MIs) (1.0%) during a median follow-up of 5.5 years. Subjects with weight gain ≥ 10% had a significantly higher risk of stroke (hazard ratio [HR] 1.51, 95% confidence interval [CI] 1.23-1.84), compared with the group with stable weight. There was no significant association between weight change after diagnosis of DM and incident MI. All-cause mortality showed a U-shaped curve according to weight change. The group with weight loss ≥ - 10% had the highest HR for all-cause mortality (HR 1.86; 95% CI 1.61-2.14) and the HR for weight gain ≥ 10% was 1.61 (95% CI 1.37-1.89).

CONCLUSIONS

Weight changes of more than 10% after diabetes diagnosis were associated with higher mortality and over 10% weight gain was associated with increased risk of stroke.

The diagnostic and initial approach of the patient with non-alcoholic fatty liver disease: role of the primary care provider

Non-alcoholic fatty liver disease (NAFLD) represents a broad spectrum of liver damage, ranging from simple steatosis to steatohepatitis and fibrosis; as well, there is a close association between NAFLD, obesity, metabolic syndrome and type 2 diabetes mellitus. There is a certain degree of uncertainty regarding the natural history and prognosis of NAFLD; however, several methods are currently used for its diagnostic approach. In the first instance, non-invasive tests could be used to identify patients at low risk of developing fibrosis and to establish more easily the need for a liver biopsy, whose accuracy in the evaluation of fibrosis has been questioned, mainly due to errors of intra and interobserver sampling, technical problems and cost, which limits its use. Therefore, it is essential to determine the diagnostic strategy for patients with NAFLD.

The effects of metabolic status on non-alcoholic fatty liver disease-related outcomes, beyond the presence of obesity

BACKGROUND

Metabolically healthy obesity (MHO) shows a reduced risk compared with obese patients with adverse metabolic conditions. Lean people suffering some metabolic derangements also have non-alcoholic fatty liver disease (NAFLD)-related outcomes compared with non-obese subjects with a few metabolic risks.

AIM

To define the impact of the metabolic status on the NAFLD-related outcomes, beyond the presence of obesity.

METHODS

We designed a multicentre cross-sectional study, including 1058 biopsy-proven NAFLD patients. Metabolically healthy status was strictly defined by the lack of metabolic risk factors (diabetes mellitus, low HDL, hypertriglyceridemia, arterial hypertension). Non-alcoholic steatohepatitis (NASH) and significant fibrosis (F2-F4) were identified by liver biopsy. Chronic kidney disease epidemiology collaboration equation was calculated for kidney function and the atherogenic index of plasma (AIP) for cardiovascular risk.

RESULTS

Metabolically healthy (OR 1.88; P = 0.050) and unhealthy obesity (OR 3.47: P < 0.0001), and unhealthy non-obesity (OR 3.70; P < 0.0001) were independently associated with NASH together with homeostatic model assessment (HOMA), ALT, and platelets. Significant fibrosis was more frequently observed in the presence of adverse metabolic conditions in obese (OR 3.89; P = 0.003) and non-obese patients (OR 3.92; P = 0.002), and independently associated with platelets, albumin, ALT, HOMA, and age. The number of metabolic factors determined the risk of NASH and significant fibrosis. Glomerular filtration rate was lower in unhealthy (91.7 ± 18) than healthy metabolism (95.6 ± 17) (P = 0.007). AIP was higher in adverse metabolic conditions (P = 0.0001). Metabolically unhealthy non-obesity showed higher liver damage (NASH 55.8% vs 42.4%; P < 0.05; significant fibrosis 31.7% vs 11.4%; P < 0.0001) and cardiovascular risk (P < 0.0001) than healthy obesity.

CONCLUSIONS

Metabolic unhealthy status showed a greater impact on NASH, significant fibrosis, kidney dysfunction, and atherogenic profile than obesity. However, metabolically healthy obesity was not a full healthy condition. We should focus our messages especially on patients with adverse metabolic conditions.

Non-Alcoholic Fatty Liver Disease: The Emerging Burden in Cardiometabolic and Renal Diseases

As the number of individuals with non-alcoholic fatty liver disease (NAFLD) has increased, the influence of NAFLD on other metabolic diseases has been highlighted. Accumulating epidemiologic evidence indicates that NAFLD not only affects the liver but also increases the risk of extra-hepatic diseases such as type 2 diabetes mellitus, metabolic syndrome, dyslipidemia, hypertension, cardiovascular or cerebrovascular diseases, and chronic kidney disease. Non-alcoholic steatohepatitis, an advanced type of NAFLD, can aggravate these inter-organ relationships and lead to poorer outcomes. NAFLD induces insulin resistance and exacerbates systemic chronic inflammation and oxidative stress, which leads to organ dysfunction in extra-hepatic tissues. Although more research is needed to identify the pathophysiological mechanisms and causal relationship between NAFLD and cardiometabolic and renal diseases, screening for heart, brain, and kidney diseases, risk assessment for diabetes, and a multidisciplinary approach for managing these patients should be highly encouraged.

The Effects of Exercise on Abdominal Fat and Liver Enzymes in Pediatric Obesity: A Systematic Review and Meta-Analysis

BACKGROUND

Despite the prevalence of obesity and the multiple position stands promoting exercise for the treatment of obesity and hepatic function, a meta-analytic approach has not previously been used to examine the effects in the pediatric population. The aim of the study was to determine the effectiveness of exercise interventions on abdominal fat, liver enzymes, and intrahepatic fat in overweight and obese youth.

MATERIALS AND METHODS

A computerized search was made using three databases. The analysis was restricted to studies that examined the effect of supervised exercise interventions on abdominal fat (visceral and subcutaneous fat), liver enzymes (alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase), and intrahepatic fat. Fourteen clinical trials (1231 youths) were eligible for inclusion in this systematic review and meta-analysis. Standardized mean difference [SMD] and 95% confidence intervals (CIs) were calculated.

RESULTS

Exercise was associated with a significant reduction in visceral (SMD = -0.661; 95% CI, -0.976 to -0.346; p < 0.001), subcutaneous (SMD = -0.352; 95% CI, -0.517 to -0.186; p < 0.001) and intrahepatic fat (SMD = -0.802; 95% CI, -1.124 to -0.480; p < 0.001), as well as gamma-glutamyl transferase (SMD = -0.726; 95% CI, -1.203 to -0.249; p < 0.001), but did not alter any other liver enzyme. Subgroup analysis recommends exercise programs that involve aerobic exercise longer than three sessions per week.

CONCLUSIONS

This meta-analysis supports current recommendation for physical exercise, mainly aerobic, as an effective intervention for nonalcoholic fatty liver disease progression by targeting hepatic lipid composition, visceral and subcutaneous adipose tissue. Systematic review registration: PROSPERO CRD42016042163.

Dissecting the relationship between obesity and hyperinsulinemia: Role of insulin secretion and insulin clearance

OBJECTIVE

The aim of this study was to better delineate the complex interrelationship among insulin resistance (IR), secretion rate (ISR), and clearance rate (ICR) to increase plasma insulin concentrations in obesity.

METHODS

Healthy volunteers (92 nondiabetic individuals) had an insulin suppression test to measure IR and graded-glucose infusion test to measure ISR and ICR. Obesity was defined as a body mass index (BMI) ≥30 kg/m² , and IR was defined as steady-state plasma glucose (SSPG) ≥10 mmol/L during the insulin suppression test. Plasma glucose and insulin concentrations, ISR, and ICR were compared in three groups: insulin sensitive/overweight; insulin sensitive/obesity; and insulin resistant/obesity.

RESULTS

Compared with the insulin-sensitive/overweight group, the insulin-sensitive/obesity had significantly higher insulin area under the curve (AUC) and ISR AUC during the graded-glucose infusion test (P < 0.001). Glucose AUC and ICR were similar. The insulin-resistant/obesity group had higher insulin AUC and ISR AUC compared with the insulin-sensitive/obesity but also had higher glucose AUC and decreased ICR (P < 0.01). In multivariate analysis, both BMI and SSPG were significantly associated with ISR.

CONCLUSIONS

Plasma insulin concentration and ISR are increased in individuals with obesity, irrespective of degree of IR, but a decrease in ICR is confined to the subset of individuals with IR.

Lean, but not healthy: the 'metabolically obese, normal-weight' phenotype

PURPOSE OF REVIEW

Obesity is commonly associated with metabolic dysfunction but there are obese persons who are metabolically healthy. On the opposite side of the coin, there are lean persons who carry multiple cardiometabolic risk factors, typically referred to as metabolically obese, normal-weight (MONW). This has called into question our understanding of obesity and metabolic dysfunction, as an appearance of normal weight may mask significant comorbidities and delay health interventions.

RECENT FINDINGS

High heterogeneity in MONW prevalence rates has been observed, with estimates ranging from as low as 5% to as high as 45%. Reasons for this include sample size effects, differences in MONW definition, social and demographic factors, as well as assumptions made in establishing normal weight. MONW study participants are often characterized by excess visceral adipose tissue and ectopic fat deposition, adipose tissue inflammation, altered inflammatory and adipokine profiles, reduced skeletal muscle mass and low cardiorespiratory fitness. However, more often than not, groups of MONW study participants have been somewhat 'fatter' than the control groups of metabolically healthy lean study participants, which in itself could be responsible for some of the observed differences. Very limited data are available regarding interventions to improve metabolic function in MONW study participants.

SUMMARY

There is a need for more research to better understand the characteristics of the MONW phenotype, the cause of metabolic dysfunction in the absence of obesity, and evaluate potential therapies so as to facilitate the establishment of clinical guidelines.

Predictive Value of Triglyceride Glucose Index for the Risk of Incident Diabetes: A 4-Year Retrospective Longitudinal Study

The Triglyceride Glucose Index (TyG index) is considered a surrogate marker of insulin resistance. The aim of this study is to investigate whether the TyG index has a predictive role in identifying individuals with a high risk of incident diabetes and to compare it with other indicators of metabolic health. A total 2900 non-diabetic adults who attended five consecutive annual health check-ups at Kangbuk Samsung Hospital was divided into four subgroups using three methods: (1) baseline TyG index; (2) obesity status (body mass index ≥25 kg/m2) and cutoff value of TyG index; (3) obesity status and metabolic health, defined as having fewer than two of the five components of high blood pressure, fasting blood glucose, triglyceride, low high-density lipoprotein cholesterol, and highest decile of homeostasis model assessment-insulin resistance. The development of diabetes was assessed annually using self-questionnaire, fasting glucose, and glycated hemoglobin. We compared the risk of incident diabetes using multivariate Cox analysis. During 11623 person-years there were 101 case of incident diabetes. Subjects with high TyG index had a high risk of diabetes. For TyG index quartiles, hazard ratios (HRs) of quartiles 3 and 4 were 4.06 (p = 0.033) and 5.65 (p = 0.006) respectively. When the subjects were divided by obesity status and cutoff value of TyG index of 8.8, the subgroups with TyG index ≥ 8.8 regardless of obesity had a significantly high risk for diabetes (HR 2.40 [p = 0.024] and 2.25 [p = 0.048]). For obesity status and metabolic health, the two metabolically unhealthy subgroups regardless of obesity had a significantly high risk for diabetes (HRs 2.54 [p = 0.024] and 2.73 [p = 0.021]). In conclusion, the TyG index measured at a single time point may be an indicator of the risk for incident diabetes. The predictive value of the TyG index was comparable to that of metabolic health.