Normal weight obesity among young adults in Trinidad and Tobago: prevalence and associated factors

Characterization and prevalence of obesity among normal weight college students

Normal weight obesity (NWO) describes individuals who have a normal weight body mass index (BMI), but have an unhealthy amount of body fat. Based on the life-long habits that develop during college, exploring NWO among a college-aged population may be essential in identifying and preventing obesity that develops in early adulthood. This study aimed to characterize NWO among young adults with normal weight BMI. 94 college students (Mean ± SD: Age: 19.6 ± 1.5 yrs; BMI: 21.9 ± 1.8 kg/m²) enrolled during the Fall semester (Aug-Oct) were assessed for body composition by dual energy X-ray absorptiometry to determine body fat percentage, fat mass, lean mass and trunk fat; lifestyle habits were characterized from validated questionnaires. Mean arterial pressure and metabolic biomarkers [total cholesterol, high density lipoproteins, non-high density lipoproteins, and glucose] were evaluated for cardiometabolic health. NWO was defined using data from the National Health and Nutrition Examination Survey (NHANES) for body fat percentage. Data was analyzed by group (NWO vs NWL) and sex. with independent t-tests to investigate continuous data, and chi-square test of independence for categorical data. Rates of NWO for the total sample were 13.8%. Males (n=30) had a higher rate of NWO (26.7%) compared to females (n=64; 7.8%). NWO individuals had higher fat mass (p=0.024), trunk fat (p<0.001), and larger waist to hip ratio (p<0.001) than normal weight lean. NWO also engaged in less vigorous physical activity (p=0.043). The occurrence of NWO among otherwise healthy college students is evident. Identification of these individuals may be an effective component for obesity prevention and treatment. Determining feasible methods to measure body fat in this population is essential, as BMI may mask obesity in a young adult population.

Non-invasive type 2 diabetes risk scores do not identify diabetes when the cause is β-cell failure: The Africans in America study

Background

Emerging data suggests that in sub-Saharan Africa β-cell-failure in the absence of obesity is a frequent cause of type 2 diabetes (diabetes). Traditional diabetes risk scores assume that obesity-linked insulin resistance is the primary cause of diabetes. Hence, it is unknown whether diabetes risk scores detect undiagnosed diabetes when the cause is β-cell-failure.

Aims

In 528 African-born Blacks living in the United States [age 38 ± 10 (Mean ± SE); 64% male; BMI 28 ± 5 kg/m²] we determined the: (1) prevalence of previously undiagnosed diabetes, (2) prevalence of diabetes due to β-cell-failure vs. insulin resistance; and (3) the ability of six diabetes risk scores [Cambridge, Finnish Diabetes Risk Score (FINDRISC), Kuwaiti, Omani, Rotterdam, and SUNSET] to detect previously undiagnosed diabetes due to either β-cell-failure or insulin resistance.

Methods

Diabetes was diagnosed by glucose criteria of the OGTT and/or HbA1c ≥ 6.5%. Insulin resistance was defined by the lowest quartile of the Matsuda index (≤ 2.04). Diabetes due to β-cell-failure required diagnosis of diabetes in the absence of insulin resistance. Demographics, body mass index (BMI), waist circumference, visceral adipose tissue (VAT), family medical history, smoking status, blood pressure, antihypertensive medication, and blood lipid profiles were obtained. Area under the Receiver Operator Characteristics Curve (AROC) estimated sensitivity and specificity of each continuous score. AROC criteria were: Outstanding: >0.90; Excellent: 0.80-0.89; Acceptable: 0.70-0.79; Poor: 0.50-0.69; and No Discrimination: 0.50.

Results

Prevalence of diabetes was 9% (46/528). Of the diabetes cases, β-cell-failure occurred in 43% (20/46) and insulin resistance in 57% (26/46). The β-cell-failure group had lower BMI (27 ± 4 vs. 31 ± 5 kg/m² P < 0.001), lower waist circumference (91 ± 10 vs. 101 ± 10cm P < 0.001) and lower VAT (119 ± 65 vs. 183 ± 63 cm³, P < 0.001). Scores had indiscriminate or poor detection of diabetes due to β-cell-failure (FINDRISC AROC = 0.49 to Cambridge AROC = 0.62). Scores showed poor to excellent detection of diabetes due to insulin resistance, (Cambridge AROC = 0.69, to Kuwaiti AROC = 0.81).

Conclusions

At a prevalence of 43%, β-cell-failure accounted for nearly half of the cases of diabetes. All six diabetes risk scores failed to detect previously undiagnosed diabetes due to β-cell-failure while effectively identifying diabetes when the etiology was insulin resistance. Diabetes risk scores which correctly classify diabetes due to β-cell-failure are urgently needed.

Cardiometabolic risk factors in adults with normal weight obesity: A systematic review and meta-analysis

Normal weight obesity (NWO) is a new emerging phenotype of obesity, defined as a normal body mass index with a high body fat percentage. While several studies have described the impact of NWO on cardiometabolic risk factors, the association between them remains uncertain. This meta-analysis systematically evaluated cardiometabolic risk factors in adults with NWO compared to adults with normal weight lean (NWL). A systematic literature search was performed from the inception until September 21, 2021 in order to comprehensively search for all observational studies that had three important variables, including adults (age ≥18 years old), NWO and cardiometabolic risk factors including metabolic syndrome, hypertension, diabetes mellitus, dyslipidaemia or all laboratory findings related to cardiometabolic risk factors. Twenty-four cross-sectional studies with a total of 75 201 subjects are included in the qualitative and quantitative analysis. Overall, older age and female sex are more likely in NWO population. Compared to NWL, NWO is significantly associated with cardiometabolic risk factors, including metabolic syndrome (OR = 2.24 [1.74, 2.89]; p < .001; I²  = 76%, P_{heterogeneity}  < 0.001), hypertension (OR = 1.60[1.36, 1.89]; p < .001; I²  = 76%, P_{heterogeneity}  < 0.001), diabetes mellitus (OR = 1.72[1.54, 1.92]; p < .001; I²  = 47%, P_{heterogeneity}  < 0.001), dyslipidaemia (OR = 1.50 [1.03, 2.18]; p = .03; I²  = 94%, P_{heterogeneity}  < 0.001) and other laboratory findings, except for C-reactive protein in both sexes group; and adiponectin levels in female group. Our meta-analysis showed that NWO was associated with cardiometabolic risk factors. Thus, the traditional definition of obesity using the BMI criteria should be challenged, as those with NWO might still be exposed to a heightened risk of cardiometabolic disorders. Nonetheless, further prospective cohort studies are needed better to understand this syndrome.

Normal Weight Obesity and Cardiometabolic Risk Factors: A Systematic Review and Meta-Analysis

BACKGROUND

Obesity is one of the most significant causes of morbidity and mortality worldwide. Current studies suggest a new type of obesity, normal weight obesity (NWO), which is defined as having a normal body mass index (BMI), but a high-fat percentage increases the risk of cardiometabolic risk factors (CMRFs). This systematic review and meta-analysis aimed to pool the association between NWO with CMRFs.

METHODS

A systematic search of the literature in all available electronic databases, including Scopus, Web of Science, EMBASE, and PubMed, was performed until October 2021. All English studies that assessed the association of NWOs [compared to normal weight non-obese (NWNO)] and the CMRFs were included. Two investigators extracted data and performed a quality assessment. The heterogeneity between studies was assessed with I-squared and Cochran's Q tests. Odds ratio (OR) was used as an effect size to pool the association of NWO with CMRFs.

RESULTS

Twenty-five articles that met the inclusion criteria entered the study. The total number of participants was 177,792, with an age range of 13 to 75 years. Most studies were conducted on the general population (adults) and were from China. The result of fixed-effect model meta-analysis indicated an increased odds of hyperglycemia (OR:1.50, 95%:1.23, 1.76), high TG (OR:1.90, 95% CH:1.44, 2.35), low HDL (OR: 1.28, 95% CI:1.06, 1.49) and diabetes (OR:1.39, 95% CI:1.30, 1.49). Moreover, the random effect meta-analysis showed that NWO increased the odds of dyslipidemia (OR:1.83, 95% CI:1.61, 20.4), HTN (OR:1.40, 95% CI:1.28, 1.51) and metabolic syndrome (OR:1.92, 95% CI:1.58, 2.26). Moreover, the mean of all CMRFs except plasma glucose in NWO subjects was statistically higher than NWNO subjects (p-value<0.05).

CONCLUSION

The present study showed that NWO increased the odds of CMRFs. These findings indicate the inadequacy of the BMI measurement and the need for body fat assessment for a better obesity risk assessment.

Normal weight obesity and unaddressed cardiometabolic health risk-a narrative review

Normal weight obesity (NWO) is defined as having a normal body mass index (BMI), but a high body fat mass. There is growing interest in individuals with NWO, which is an underdiagnosed and understudied group, because of their increased risk for cardiometabolic morbidity and mortality. In this review, we summarized the definition, prevalence, etiology, pathophysiology, and cardiovascular outcomes seen in NWO. We have also summarized the available literature on interventions for NWO. There is a wide variation in the body fat percent cutoffs used to diagnose excess body fat. Hence, the prevalence rates of NWO vary between different populations and studies. It is estimated that about 30 million Americans have NWO and the worldwide prevalence ranges from 4.5% to 22%. Genetics, diet, and physical activity are related to NWO. However, etiological factors are not clear. Changes in body composition, inflammation, oxidative stress are present in NWO in comparison to normal weight lean (NWL) who have a normal BMI and normal body fat amount. Furthermore, cardiometabolic changes are observed and some are subclinical. Thus, screening for NWO will enhance the primary prevention of cardiovascular disease. Due to the use of various body fat percent cutoffs and methods to measure body fat, it is challenging to compare between studies. Researchers working in this field should ideally work towards developing standard body fat percent cutoffs for diagnosing NWO. There are many gaps in the literature on NWO unlike for overt obesity and future studies should explore the etiology, molecular mechanisms, and adipose tissue changes of NWO as well as conduct well planned and executed randomized controlled trials testing dietary, physical, and behavioral interventions for NWO in both males and females of different racial and age groups.

Anthropometric measures of obesity and associated cardiovascular disease risk in the Eastern Caribbean Health Outcomes Research Network (ECHORN) Cohort Study

BACKGROUND

Accurately defining obesity using anthropometric measures that best capture obesity-related risk is important for identifying high risk groups for intervention. The purpose of this study is to compare the association of different anthropometric measures of obesity with 10-year cardiovascular disease (CVD) risk in adults in the Eastern Caribbean.

METHODS

Data from the Eastern Caribbean Health Outcomes Research Network (ECHORN) Cohort Study (ECS) were analyzed. The ECS is comprised of adults aged 40 and older residing in the US Virgin Islands, Puerto Rico, Barbados, and Trinidad. 10-year CVD risk was calculated using the American Heart Association (ACC/AHA) ASCVD Risk Algorithm and categorized in the following high-risk groups: > 7.5, > 10, and > 20%. Logistic regression was used to examine associations between four anthropometric measures of obesity (BMI, waist circumference, waist-to-hip ratio, waist-to height ratio) and 10-year CVD risk.

RESULTS

Mean age (SD) of participants (n = 1617) was 56.6 years (±10.2), 64% were women, 74% were overweight/obese, and 24% had an ASCVD risk score above 10%. Elevated body mass index (BMI, > 30 kg/m2) and waist circumference were not associated with CVD risk. Elevated waist-to-hip ratio (WHR, > 0.9 men, > 0.85 women) and elevated waist-to-height ratio (> 0.5) were associated with all three categories of CVD risk. Area under the receiver curve was highest for WHR for each category of CVD risk. Elevated WHR demonstrated odds of 2.39, 2.58, and 3.32 (p < 0.0001) for CVD risk of > 7.5, > 10 and > 20% respectively.

CONCLUSION

Findings suggest that WHR is a better indicator than BMI of obesity-related CVD risk and should be used to target adults in the Caribbean, and of Caribbean-descent, for interventions.

Physical Fitness but Not Diet Quality Distinguishes Lean and Normal Weight Obese Adults

BACKGROUND

Individuals with normal weight obesity (NWO) have increased cardiometabolic disease and mortality risk, but factors contributing to NWO development are unknown.

OBJECTIVE

The objective of this study was to determine whether diet quality scores and physical fitness levels differed between adults classified as lean, NWO, and overweight-obese. Secondary objectives of the study were to compare clinical biomarkers and food groups and macronutrient intakes between the three groups, and to test for associations between body composition components with diet quality scores and physical fitness levels.

DESIGN

This is a secondary data analysis from a cross-sectional study that included metropolitan university and health care system employees. Body composition was measured by dual energy x-ray absorptiometry. Individuals with a body mass index <25 kg/m2 and body fat >23% for men and >30% for women were classified as having NWO. Alternate Healthy Eating Index, Dietary Approaches to Stop Hypertension score, and Mediterranean Diet Score were calculated from Block food frequency questionnaires. Physical fitness was assessed by measuring maximal oxygen uptake (VO2 maximum) during treadmill testing.

PARTICIPANTS/SETTING

This study included 693 adults (65% women, mean age 48.9 ± 11.5 years) enrolled between 2007 and 2013 in Atlanta, GA.

MAIN OUTCOME MEASURES

The main outcome measures were Alternate Healthy Eating Index, Dietary Approaches to Stop Hypertension, and Mediterranean Diet Score diet quality scores and maximal oxygen uptake.

STATISTICAL ANALYSES

Multiple linear regression analyses with post hoc comparisons were used to investigate group differences in fitness, diet quality, and biomarkers. Regression analyses were also used to examine relationships between diet quality scores and fitness with body composition.

RESULTS

VO2 maximum was significantly lower in the NWO compared with the lean group (36.2 ± 0.8 mL/min/kg vs 40.2 ± 1.0 mL/min/kg; P < 0.05). Individuals with NWO reported similar diet quality to lean individuals and more favorable Alternate Healthy Eating Index and Dietary Approaches to Stop Hypertension scores than individuals with overweight-obesity (P < 0.05). Diet quality scores and physical fitness levels were inversely associated with percent body fat and visceral adipose tissue (P < 0.05), regardless of weight status. Individuals with NWO exhibited higher fasting blood insulin concentrations, insulin resistance, low-density lipoprotein cholesterol, and triglyceride levels, and significantly lower high-density lipoprotein cholesterol levels than lean individuals (P < 0.05).

CONCLUSIONS

Physical fitness was significantly decreased in individuals with NWO compared with lean individuals. Higher diet quality was associated with decreased total and visceral fat but did not distinguish individuals with NWO from lean individuals.

An updated systematic review and meta-analysis on the social determinants of diabetes and related risk factors in the Caribbean

OBJECTIVES

To conduct an analysis of the most recent data on diabetes and its risk factors by gender and other social determinants of health to understand why its prevalence is higher among women than men in the Caribbean; to inform policy agenda-setting for diabetes prevention and control in the Caribbean; and to identify gaps in the evidence that require further research.

METHODS

A previous systematic review of the literature describing studies conducted in the Caribbean that presented the distribution of diabetes, its outcomes, and risk factors, by one or more social determinants, was updated to include sources from 1 January 2007 - 31 December 2016. Surveys by the World Health Organization (WHO) were also included. Where data were sufficient, meta-analyses were undertaken.

RESULTS

A total of 8 326 manuscripts were identified. Of those, 282 were selected for full text review, and 114, for abstraction. In all, 36 papers, including WHO-related surveys, had sufficient information for meta-analysis. More women compared to men were obese (OR: 2.1; 95%CI = 1.65 - 2.69), physically inactive (OR: 2.18; 95%CI = 1.75 - 2.72), and had diabetes (OR: 1.48; 95%CI = 1.25 - 1.76). More men smoked (OR: 4.27; 95%CI = 3.18 - 5.74) and had inadequate fruit and vegetable intake (OR: 1.37; 95%CI = 1.21 - 1.57).

CONCLUSION

Thirty-six papers were added to the previously conducted systematic review; of those, 13 were added to the meta-analysis. Diabetes and its risk factors (primarily obesity and physical inactivity) continue to disproportionately affect women in the Caribbean. Smoking interventions should be targeted at men in this geographic area.