Adolescence metabolic syndrome or adiposity and early adult metabolic syndrome

Metabolic risk assessment in children and adolescents using the tri-ponderal mass index

We assessed the risk of metabolic syndrome in children and adolescents who were classified using the tri-ponderal mass index (TMI) with data from the Korea National Health and Nutrition Examination Survey (KNHANES). Data from 10 to 18-year-old subjects that were overweight or obese (n = 1362) were extracted from the KNHANES 2007-2018. Weight classifications were determined by TMI and included overweight and Class I, Class II, and Class III obesity. The standard deviation scores (SDS) of weight, waist circumference, and body mass index (BMI) as well as cardiometabolic risk factors, including blood pressure, serum glucose levels, total cholesterol (T-C), triglycerides, HDL-c, and low-density lipoprotein cholesterol (LDL-c), worsened with the severity of obesity. Most risk factors showed a linear association with the severity increase, except for fasting glucose levels, T-C, and LDL-c. The prevalence of cardiometabolic risks also increased with the severity of obesity, which developed earlier in boys than in girls. The risk of metabolic syndrome significantly increased with the severity of obesity in both unadjusted and adjusted analyses. TMI reflected the severity of obesity and predicted the risk of metabolic syndrome and its components. Therefore, clinical applications of TMI could be a useful to identify the incidence of childhood obesity and metabolic syndromes.

Association between preventable risk factors and metabolic syndrome

The risk factors associated with metabolic syndrome (Met-S) including hypertension, hyperglycemia, central obesity, and dyslipidemia are preventable, particularly at their early stage. There are limited data available on the association between Met-S and preventable risk factors in young adults. We randomly selected 2,010 Saudis aged 18-30 years, who applied to be recruited in military colleges. All the procedures followed the guidelines of International Diabetes Federation. The results showed that out of 2,010 subjects, 4088 were affected with Met-S. The commonest risk factors were high blood sugar (63.6%), high systolic and diastolic blood pressures (63.3 and 37.3%), and high body mass index (57.5%). The prevalence of prediabetes and diabetes were 55.2 and 8.4%, respectively. Obesity, diabetes, hypertension, and hypertriglyceridemia were significantly associated with Met-S. The frequency of smoking was significantly linked with the development of Met-S. The prevalence of Met-S was found to be significantly higher in individuals with sedentary lifestyle. In conclusion, the results of this study clearly indicate that military recruits, who represent healthy young adults, are also prone to Met-S. The findings of this study will help in designing preventive measures as well as public awareness programs for controlling the high prevalence of Met-S in young adults.

Association of childhood obesity phenotypes with early adulthood Carotid Intima-Media Thickness (CIMT): Tehran lipid and glucose study

BACKGROUND AND AIMS

Over the past few years, obesity and metabolic syndrome prevalence among children and adolescence have an increasing trend. This study aims to investigate the association of obesity phenotypes during childhood and adolescence with early adulthood carotid intima-media thickness (CIMT).

METHODS AND RESULTS

Participants were divided into four obesity phenotypes: Metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO). Participants were followed for 18 years. Multivariate-adjusted Risk Ratios (RRs) were calculated for high CIMT (≥95% percentile) incidence. In this cohort study 1220 children and adolescents with the average age of 10.9 ± 4.0 years were included. CIMT values had a significantly increasing trend from MHNW to MUO group (p for trend<0.001). Individuals with normal weight status, even with an unhealthy metabolic profile did not have higher risk of high CIMT. Similarly, Children with obesity but healthy metabolic status was not at higher risk. On the other hand, MUO phenotype during childhood was associated with increased risk of high CIMT in early adulthood (RR = 2.13, 95%CI (1.02-4.48)). This association became insignificant for all obesity phenotypes after adjusting for adulthood BMI.

CONCLUSION

Adulthood CIMT has an increasing trend based on childhood and adolescence obesity phenotypes from MHNW to MUO. Children with MUO phenotype was the only ones that had an increased risk of high CIMT incidence in early adulthood.

Association of childhood metabolic syndrome and metabolic phenotypes with the carotid intima-media thickness (CIMT) in early adulthood: Tehran lipid and glucose study

BACKGROUND

The clinical significance of metabolic syndrome (MetS) during adolescence and its association with adulthood adverse outcomes is a controversial issue. This study aimed to investigate the association of MetS and metabolic phenotypes with a high carotid intima-media thickness (CIMT) in early adulthood.

METHODS

MetS was defined as proposed by Cook, de Ferranti, the National Cholesterol Education Program (NCEP), and the pediatric International Diabetes Federation (IDF). Metabolic phenotypes were defined based on the binary clustering of cardiovascular risk factors. The participants were adolescent's individual selected from a large cohort study and followed for 18.2 years. Multivariate-adjusted odds ratios (ORs) were calculated for a high CIMT incidence (≥95th percentile).

RESULTS

In this study, 862 adolescents (52.3% males), with the mean age of 13.4 ± 2.2 years, were included. The presence of MetS, based on the definitions proposed by Cook (OR = 1.90, 95% CI: 1.01-3.57, P = 0.046) and de Ferranti (OR = 1.74; 95% CI: 1.04-2.90, P = 0.033), was associated with the increased risk of a high CIMT in early adulthood. Metabolic phenotypes, including high waist circumference (WC)/hypertension (HTN), high WC/low high-density lipoprotein-cholesterol (HDL-C), and high triglyceride (TG)/high WC, showed higher risks of a high CIMT. However, these positive associations become insignificant after adjusting for the adulthood BMI, except for the high WC/low HDL-C phenotype (OR = 2.04, 95% CI: 1.02-4.11, P = 0.044).

CONCLUSION

The high WC/low HDL-C phenotype had a better predictive value and could be used as a simpler alternative for MetS to identify adolescents with a higher risk of high CIMT during early adulthood.

Weight change from childhood to adulthood and cardiovascular risk factors and outcomes in adulthood: A systematic review of the literature

The magnitude of the associations between life-course change in weight status and health outcomes in adulthood has been inconsistent. This study aims to examine the associations between weight change from childhood to adulthood and cardiovascular disease (CVD) risk factors and outcomes in adulthood. PubMed, Embase and ISI Web of Science between 1 August 1953 and 13 July 2020 were searched, and a total of 52 eligible articles were included. The systematic review supported significant associations between the life-course increase in BMI and high odds of markers in adulthood. In the meta-analyses, normal weight in childhood but excess weight in adulthood or persistent excess weight was associated with increased odds of adult markers. However, those who had excess weight in childhood but were normal weight in adulthood did not have increased odds of nearly all adult markers. This systematic review and meta-analysis suggest that individuals who developed excess weight in adulthood or had excess weight in both periods had higher odds of developing CVD risk factors and outcomes in adulthood. In contrast, the probability of these adult markers could be limited or eliminated for children with excess weight who are able to become adults with normal weight.

The prevalence of pediatric metabolic syndrome-a critical look on the discrepancies between definitions and its clinical importance

Introduction

The Metabolic Syndrome (MetS) describes the clustering of cardio-metabolic risk factors—including abdominal obesity, insulin resistance, elevated blood pressure, high levels of triglycerides, and low levels of high-density lipoproteins—that increase the risk for developing cardiovascular diseases and type 2 diabetes mellitus. However, a generally accepted definition of MetS in pediatric patients is still lacking.

Objectives

The aim was to summarize current prevalence data of childhood MetS as well as to discuss the continuing disagreement between different pediatric definitions and the clinical importance of such diagnosis.

Methodology

A systematic literature search on the prevalence of pediatric MetS was conducted. Articles that were published during the past 5 years (2014–2019), using at least one of four predetermined classifications (International Diabetes Federation, Cook et al., Ford et al., and de Ferranti et al.), were included.

Results

The search resulted in 1167 articles, of which 31 publications met all inclusion criteria.

Discussion

The prevalence of MetS ranged between 0.3 and 26.4%, whereby the rising number of children and adolescents with MetS partly depended on the definition used. The IDF definition generally provided the lowest prevalences (0.3–9.5%), whereas the classification of de Ferranti et al. yielded the highest (4.0–26.4%). In order to develop a more valid definition, further research on long-term consequences of childhood risk factors such as abdominal obesity, insulin resistance, hypertension, and dyslipidemia is needed. There is also a temptation to suggest one valid, globally accepted definition of metabolic syndrome for pediatric populations but we believe that it is more appropriate to suggest definitions of MetS that are specific to males vs. females, as well as being specific to race/ethnicity or geographic region. Finally, while this notion of definitions of MetS specific to certain subgroups is important, it still needs to be tested in future research.

Prevalence and Incidence of Metabolic Syndrome in Iran: A Systematic Review and Meta-Analysis

Metabolic syndrome (MetS) is a predictor of several diseases such as cardiovascular diseases, diabetes, dyslipidemia, stroke, osteoarthritis, certain cancers, and death leading to public health concern in most societies. We aimed to estimate the pooled prevalence and incidence of MetS in Iranian population through a meta-analysis study. We included cross-sectional and cohort studies to estimate the overall prevalence and incidence rates of MetS in Iran National databases including MagIran, Science Information Database, IranMedex, and international databases including Medline, Web of Sciences, and Scopus were searched up to October 2017. Finally, 125 studies were included. The total sample size was 472,401 with a mean age of 38 ± 7.8 years. The overall pooled prevalence and incidence rate among the general population of Iran was 0.26 (95% CI: 0.26, 0.29) and 97.96 (95% CI: 75.98, 131.48), respectively. The pooled prevalence of MetS was higher in females and in urban areas. The highest and lowest prevalence of MetS was obtained by the Iranian definition criteria (0.43) and the NHANES III (0.12). The highest and lowest incidence rates of MetS were obtained by IDF (144.07 per 1000) and the JIS (89.73 per 1000). The prevalence of MetS was higher in women and those living in urban areas. Furthermore, the prevalence of MetS increased with increasing age in both genders.

Metabolic Syndrome: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

In recent decades, investigations have been focused on the definition, incidence and predictors of metabolic syndrome (MetS) in Iranians. This study aimed to review systematically investigations on MetS, conducted among the Tehran lipid and glucose study (TLGS) participants.

EVIDENCE ACQUISITION

Literature on MetS documented by TLGS studies published from 2000 to 2017 were searched using Pubmed and Scopus database in English language with a combination of following keywords: Metabolic syndrome, TLGS.

RESULTS

The harmonized definition of MetS was confirmed, based on the estimated cut point of waist circumference (WC) ≥ 95 cm for both genders in Iran. The incidence rate was 550.9/10000 person/years, lower among women (433.5/10000) than men (749.2/10000). The prevalence of abdominal obesity, high triglycerides (TG), low high density lipoprotein cholesterol (HDL-C), high blood pressure (BP), and high fasting blood glucose (FBG) was 30, 46, 69, 34, and 12%, respectively. The prevalence of MetS in adolescents was 10.1% with no significant difference between boys and girls (10.3% in boys and 9.9% in girls). A strong association of WC (OR: 2.32, CI: 2.06 - 2.59) and TGs (OR: 1.95, CI: 1.65 - 2.11) with development of MetS was found. In adolescent boys, WC had the highest OR for MetS risk. WHO-defined MetS was a significant predictor of total and cardiovascular mortality both in men (HR: 1.66, CI: 1.23 - 2.24; HR:1.93, CI: 1.26 - 2.94) and women (HR: 2.01, CI: 1.39 - 2.88; HR:2.71, CI: 1.44 - 5.09).

CONCLUSIONS

Our results indicate high incidence of MetS in Tehranian adults and adolescents; high WC also appears to be a strong predictor of MetS. All definitions of MetS predicted cardiovascular disease.

Overweight and Obesity: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

The prevalence of overweight and obesity are increasing worldwide and have frequently been associated with health risks. This review highlighted several studies regarding obesity, outlining contributions of over a span of almost two decades in the Tehran Lipid and Glucose Study (TLGS).

EVIDENCE ACQUISITION

A systematic review was undertaken to retrieve articles related to all aspects of obesity from the earliest available date up to January 30, 2017.

RESULTS

Prevalence of excess weight, including overweight and obesity were 20.8 and 63.6% among those aged below and above 20 years, respectively. TLGS found a high incidence of obesity with higher incidence in women among Tehranian adults; the cumulative incidence of obesity was 31.3, 38.1 and 23.4% for the whole population, women, and men, respectively. In children and adolescents, younger non-obese 7 - 9 years old, compared to 10 - 11 year olds are at greater risk of obesity. Prevalences of abdominal obesity in men and women were 52.8% and 44.4% respectively. Similar to generalized obesity, a high incidence of abdominal obesity was observed; the total cumulative incidence of abdominal obesity was 76.0% (83.6% for men and 70.9% for women). Metabolically healthy obese (MHO) and metabolically healthy abdominal obese (MHAO) are two important obesity phenotypes. People with these phenotypes have different risks for cardiovascular disease (CVD), type 2 diabetes (T2DM), and mortality. In the TLGS participants, MHO was found in 2% and 7.7% of the whole and obese population, respectively, whereas MHAO phenotype was reported in 12.4% and 23.5% of the whole and abdominal obese population. In these unstable conditions, during the long term follow up the metabolic risks developed in nearly half of the individuals. During a 12-year follow-up, incident CVD did not increase in the MHO phenotype compared to metabolically healthy normal weight (MHNW) individuals, but the risk of CVD events had increased in all metabolically unhealthy phenotypes. However in another report, over a 10-year follow-up, MHAO phenotype had an increased risk for CVD in comparison to the reference group, metabolically healthy non-abdominal obese (MHNAO) individuals.

CONCLUSIONS

The TLGS studies bridged the significant gap in knowledge regarding prevalence, incidence, trends, morbidities and mortalities for obesity among Iranian population.

Outcomes of a Longitudinal Population-based Cohort Study and Pragmatic Community Trial: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

The Tehran lipid and glucose study (TLGS) is one of the oldest population-based longitudinal cohort studies, providing knowledge about the incidence and risk factors of some non-communicable diseases (NCDs) in West Asia which hitherto was relatively scarce. We reviewed the methods and results related to the outcome measurements of this study.

EVIDENCE ACQUISITION

We reviewed all the TLGS papers which reported the incidence of NCDs.

RESULTS

The TLGS was initiated in 1999 - 2001 on a population in district no. 13 of Tehran with the same age distribution of the overall Tehran population and with a middle socioeconomic status. Totally, 15005 individuals, aged ≥ 3 years, participated in the first examination; reexaminations were conducted in a triennial manner and 3550 individuals were added in the second examination. All participants were also followed up annually and asked about any medical event leading to hospitalization or death. A part of participants was assigned to an educational program for lifestyle modification. High incidence of cardiovascular disease (CVD), premature CVD, diabetes and hypertension (around 19, 6, 10 and 31 in men and 11, 5, 11 and 29 in women per 1000 person-year, respectively) besides the high incidence of pre-diabetes and pre-hypertension (around 46 and 76 in men and 37 and 49 in women per 1000 person-year, respectively) showed a worrying situation. Fortunately, the results of the community interventions were promising with around 20% reduction in the risk of metabolic syndrome up to six years.

CONCLUSIONS

These precise detections of different outcomes in the TLGS provided valuable evidences for prediction and prevention of NCDs in Iran with some novelties in the middle-income countries in the world. The Tehran thyroid study (TTS) and the Tehran cardiometabolic genetic study (TCGS), conducted in the framework of the TLGS, are among few studies aiming to determine the natural course of thyroid function and to identify patterns of genetic polymorphisms related to cardiometabolic outcomes, respectively.

Metabolic syndrome prevalence in the Iranian adult's general population and its trend: A systematic review and meta-analysis of observational studies

AIMS

Metabolic syndrome (MetS) is one of the most important predictors of CVD. Determining the trend of MetS, represents the trend of its components and consequently could forecast the incidence of related diseases particularly CVD. The main object of this study is describing the trend of MetS prevalence in both male and female.

MATERIALS AND METHODS

Original research studies from March 21, 2005 to March 20, 2015 that were published in English database and Persian databases were included in the systematic review. The random effect model was used to estimate the pooled prevalence of MetS. Subgroup analyses, to portray the trend of MetS, conducted based on implementation year.

RESULTS

The total sample sizes for males using the criteria of ATP III and IDF were 30012 and 35064, and for female were 14572 and 16292. The pooled estimation of MetS prevalence in total, male, and female population according to ATP III was 28%, 23%, and 33%; for IDF definitions was 28%, 22%, and 33%. Moreover, according to meta-regression for ATP III the most important source of heterogeneity was mean age.

CONCLUSION

The findings revealed the trend of MetS prevalence is declining although steady in the last 10 years.

Instability of different adolescent metabolic syndrome definitions tracked into early adulthood metabolic syndrome: Tehran Lipid and Glucose Study (TLGS)

BACKGROUND AND OBJECTIVE

There are substantial controversies about the clinical utility of adolescent metabolic syndrome (MetS). The current study examined the stability of adolescent MetS by assessing the agreement and discriminative abilities of four different definitions of adolescent MetS and the adult MetS definition during a 10.4-yr follow up.

SUBJECTS AND METHODS

For this study, 1424 adolescents (55.2% female), who participated in the framework of the Tehran Lipid and Glucose Study were included. Kappa was calculated for agreement between adolescent MetS definitions [Cook, de Ferranti, pediatric National Cholesterol Education Program (NCEP) and pediatric International Diabetes Federation (IDF)] and the adulthood MetS definition defined by the joint interim statement (JIS) criteria. MetS persistence, instability, and incidence were assessed, and for each of the four adolescent definitions, sensitivity, specificity, and area under receiver operating curve (AUC) for the counting of categorical adulthood MetS components was evaluated.

RESULTS

The agreement between the four adolescent MetS definitions and JIS was poor (κ = 0.094-0.255). All definitions showed low sensitivity and high specificity, except for de Ferranti's, which contrary to other definitions, had higher sensitivity and lower specificity. All four adolescent definitions revealed generally low AUCs (0.601-0.647). Compared with the pubertal group (11-14 yr), the predictive power was slightly higher in the late-pubertal group (15-18 yr). Cook's and de Ferranti's definitions showed fairly better predictive powers (0.647 and 0.644, respectively). Across all definitions, instability ranged between 5.4 and 19.6%.

CONCLUSION

The adolescent definitions show considerable amount of instability defined as poor agreement and low discriminative abilities tracked into early adulthood.

Hypertriglyceridemic Waist Phenotype Indicates Insulin Resistance in Adolescents According to the Clamp Technique in the BRAMS Study

OBJECTIVE

This study aimed to identify cutoff points for detecting hypertriglyceridemic waist phenotype (HTWP) in adolescents and to investigate the association of the HTWP with insulin resistance (IR) and metabolic syndrome components.

METHODS

A multicentric cross-sectional study of 861 adolescents (10-19 years of age, 504 girls) was conducted. Pubertal stage, anthropometric, and laboratory parameters were assessed. IR was assessed by Homeostasis Model Assessment for Insulin Resistance (HOMA1-IR) index and hyperglycemic clamp (n = 80). HTWP was defined by the presence of increased plasma triglycerides (TGs) and increased waist circumference (WC) according to cutoff points obtained in ROC curve analysis given the HOMA1-IR index as a reference method.

RESULTS

Cutoffs for WC and TGs, with a higher sum of sensitivity (S) and specificity (E), were, respectively: >84 cm (S:65.1%, E:71.9%) and >87 mg/dL (S:65.1%, E:73.4%) in pubertal girls; >88.5 cm (S:80.2%, E:60.2%) and >78 mg/dL (S:60.5%, E:53.2%) in postpubertal girls; >94 cm (S:73.1%, E:83.1%) and >79 mg/dL (S:61.5%, E:60.2%) in pubertal boys; and >99 cm (S:81.3%, E:78.7%) and >86 mg/dL in postpubertal boys (S:68.1%, E:60.7%). HTWP frequency was 27.5%. In the phenotype presence, after adjustment for age and pubertal stage, blood pressure and fasting glucose levels were elevated and high-density lipoprotein cholesterol was lower (p < 0.001). Adolescents with the HTWP showed more IR, evaluated both by the HOMA1-IR and by the clamp test (p < 0.003).

CONCLUSION

The findings suggest HTWP as an IR status in adolescents. Cutoff point standardization for gender and pubertal stage, combined with the ease of application of the method, may allow their use for screening adolescents who would most benefit from lifestyle changes.

"Adolescent metabolic phenotypes and early adult metabolic syndrome: Tehran lipid and glucose study"

OBJECTIVE

To investigate the predictive role of adolescent metabolic phenotypes in development of early adult metabolic syndrome (MetS).

STUDY DESIGN

A group of 1446 adolescents (44.8% boys), participants of the Tehran Lipid and Glucose Study, with a mean (SD) of age 14.6 (2.2) years, followed for 10.4 years. Logistic regression models were developed to evaluate the predictive power of different metabolic phenotypes for adult MetS. Moreover, areas under the receiver operating characteristic (ROC) curve were estimated to compare the prediction power of metabolic phenotypes for adult MetS.

RESULTS

The prevalence of MetS was 14.6% (29.7% and 2.4% for adult males and females, respectively) at the end of follow up. The most frequent metabolic phenotype in adolescent was high TGs/low HDL-C (23.7%), while the prevalence of high TGs/high WC was 10.4% and the other phenotypes were less than 10%. After adjustment for baseline BMI Z-Score and BMI change, high TGs/low HDL-C (OR: 1.70, 95%CI: 1.23-2.37), high WC/high BP (OR: 1.75., 95%CI: 1.08-2.84), high BP/low HDL-C (OR:1.68, 95%CI: 1.05-2.60) and high WC/low HDL-C (OR: 2.41, 95% CI: 1.37-4.23) phenotypes were associated with adult MetS. However, their AUCs were significantly lower than overweight or obesity.

CONCLUSION

Some combinations of metabolic abnormalities in adolescence predict early adult MetS, independent of baseline BMI Z-Score and BMI change. However, the discriminative power of these phenotypes was weak, in comparison to adolescent overweight or obesity.

Predictors of metabolic risk in childhood obesity

Most of the complications of juvenile obesity are due to metabolic disturbances induced by an excessive accumulation of fat which leads to chronic diseases like type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Finding effective ways of identifying obese paediatric patients who are at increased risk of developing cardiovascular and metabolic complications has been recognised to be a promising strategy to improve prevention of complications of early obesity. Moreover, correctly identifying obese children who are already affected by metabolic co-morbidities should be a clinical priority. According to the state of the art summarised in this review, traditional metabolic variables included in the definitions of metabolic syndrome (MS), pre-diabetes, non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steato-hepatitis and, in obese girls, the presence of polycystic ovary syndrome are the best available longitudinal predictors of CVD and T2DM among obese children and adolescents. In clinical practice, traditional metabolic variables included in the definitions of MS should be assessed in all obese children and adolescents; fasting metabolic variables have been proposed to identify obese patients likely to be affected by impaired glucose tolerance or T2DM, and ultrasound has proved to be a valid surrogate for biopsy in the diagnosis of NAFLD. Further large longitudinal and cross-sectional studies are needed to improve our chances of identifying obese youth at the highest metabolic risk.