Changes in the prevalence of U.S. adults using diet, exercise, pharmaceuticals and diet products for weight loss over time: Analysis of NHANES 1999-2018

To examine changes in the use of diet, exercise, and pharmacological/diet product weight loss (WL) practices over time, and differences in these trends by sex and obesity status, data from the National Health and Examination Survey (NHANES Continuous 1999-2018) was used. The prevalence of diet, exercise and use of WL drugs and products over time were examined in men and women with and without obesity in a series of cross-sectional nationally representative samples (n = 43,020). Women and those with obesity were more likely to engage in WL practices over the past year, with an increased prevalence of WL efforts over time (38.4 to 43.2%). Amongst those who engaged in WL attempts, diet-related WL was most common (87-93%), followed by exercise-related WL (47-68%), whereas use of WL drugs and products was the least common (5-21%). There were modest differences in the prevalence of diet or exercise WL over time, with some differences by sex and obesity status. Most notable was the increase in the prevalence of exercise WL practices in women with obesity, with no differences among men or women without obesity. When examining specific types of diets, there were more clear differences in the adoption of diets over time, with the use of more traditional calorie/portion/fat restriction diets becoming less prevalent, and sugar/carbohydrate restriction becoming more prevalent over time (P<0.005). Changes over time in the use of diets were, were however, similar in men and women with and without obesity. Use of pharmacotherapy/diet products tended to decline in prevalence over time but was consistently highest in women with obesity. Thus, there are differences in the types of WL strategies individuals have employed over time, with variations in their popularity of use by sex and obesity status. However, the pattern of changes over time were quite similar in men and women with and without obesity.

Is anyone truly healthy? Trends in health risk factors prevalence and changes in their associations with all-cause mortality

OBJECTIVE

The purpose of the study was to determine trends in the prevalence of individual health risk factors across time and to examine if their associations with mortality have changed over time.

METHODS

Data from the National Health and Nutrition Examination Surveys (NHANES III- 1988-1994 and NHANES 1999-2014; age ≥20 years) was used to examine differences in the odds ratio (OR) of 5-year mortality risk associated with various common health risk factors over the two survey periods using weighted logistic regression analysis adjusting for age, sex, obesity category and white ethnicity (n = 28,279).

RESULTS

Over 97% of individuals had at least one of the 19 risk factors examined with no difference in the prevalence over time (P>0.34). The prevalence of lifestyle, social/mental and physical risk factors (2.2 to 19.1%) increased over time (P<0.0002), while the prevalence of having physiological risk factors decreased by ~6.5% (P<0.0001). Having any lifestyle or social/mental risk factor was significantly associated with a higher 5-year OR for mortality risk in 1999-2014, than 1988-94. In particular, having low education or use of mental health medication were not associated with mortality risk in 1988-94 (P>0.1), but were significantly associated with a higher 5-year OR for mortality in 1999-2014 (P<0.0001). Conversely, physiological risk factors were more weakly related with mortality risk in 1988-1994, than 1999-2014. Having any physical risk factor, and poor self-rated health were similarly related with 5-year mortality risk at both timepoints.

CONCLUSION

Health risk factors have both increased and decreased in prevalence over time, along with changes in the association between many of the risk factors and mortality risk. Taken together, these changes complicate interpretation of temporal trends and warrant cautious interpretation of population health patterns based on surveillance data.

Anthropometric Equations to Predict Visceral Adipose Tissue in European and American Youth

OBJECTIVE

To investigate whether prediction equations including a limited but selected number of anthropometrics that consider differences in subcutaneous abdominal adipose tissue may improve prediction of the visceral adipose tissue (VAT) in youth.

STUDY DESIGN

Anthropometrics and abdominal adipose tissue by MRI were available in 7-18 years old youth with overweight or obesity: 181 White Europeans and 186 White and Black Americans. Multivariable regressions were performed to develop and validate the VAT anthropometric predictive equations in a cross-sectional study.

RESULTS

A model with both waist circumference (WaistC) and hip circumference (HipC) (VAT = [1.594 × WaistC] - [0.681 × HipC] + [1.74 × Age] - 48.95) more strongly predicted VAT in girls of White European ethnicity (R² = 50.8%; standard error of the estimate [SEE] = 13.47 cm²), White American ethnicity (R² = 41.9%; SEE, 15.63 cm²), and Black American ethnicity (R² = 25.1%; SEE, 16.34 cm²) (P < .001), than WaistC or BMI. In boys, WaistC was the strongest predictor of VAT; HipC did not significantly improve VAT prediction.

CONCLUSIONS

A model including both WaistC and HipC that considers differences in subcutaneous abdominal adipose tissue more accurately predicts VAT in girls and is superior to commonly measured anthropometrics used individually. In boys, other anthropometric measures did not significantly contribute to the prediction of VAT beyond WaistC alone. This demonstrates that selected anthropometric predictive equations for VAT can be an accessible, cost-effective alternative to imaging methods that can be used in both clinics and research.

Association between weight-loss history and weight loss achieved in clinical obesity management: Retrospective chart review

OBJECTIVE

Weight history and its association with the weight loss achieved in a publicly funded clinical obesity management program were examined in 9348 patients.

METHODS

Weight history (frequency and magnitude of weight losses) was collected through questionnaires at enrollment, and weight change was assessed with retrospective electronic medical chart review.

RESULTS

The majority of patients reported developing overweight prior to the age of 40 years and having lost at least 4.5 kg (10 lb) of weight at least once in their lifetime. Those who had an earlier onset of overweight had a higher frequency of past weight loss and had more cumulative weight loss over their lifetime. In women, but not men, earlier age of overweight onset and lifetime weight loss were associated with modestly greater weight loss at the clinic.

CONCLUSIONS

Women with greater weight-loss history also have modestly greater weight loss at the obesity management clinic. Thus, successful long-term obesity management, particularly for women, may include a series of repeated attempts at weight loss that should not be viewed as failures but could be viewed instead as practice.

The association of objectively and subjectively measured physical activity and sedentary time with prediabetes and type 2 diabetes in adults: A cross-sectional study in Framingham Heart Study cohorts

The purpose of this study was to examine whether using both objectively (accelerometer) and subjectively (questionnaire) measured moderate- to vigorous-intensity physical activity (MVPA) and sedentary time (SED) improves the prediction of prediabetes and type 2 diabetes (pre/T2D) using data from the Framingham Heart Study (n=4200). Logistic regression was used to examine the odds ratio of pre/T2D in groups cross-classified by subjective and objective MVPA and SED. Less than half of participants fell into concordant categories of MVPA and SED using subjective and objective measures, with 7.0-9.4% of participants in the extreme discordant categories of high-low or low-high subjective-objective MVPA or SED. Low objective MVPA, regardless of subjective MVPA status, was associated with a higher prevalence of pre/T2D (P<0.05). When cross-classifying by MVPA and SED, the majority of participants fell into concordant categories of MVPA-SED, with <4% of participants in the extreme discordant categories of MVPA-SED. Low objective MVPA, regardless of objective SED, was associated with a higher prevalence of pre/T2D (P<0.05). These findings suggest that low objectively measured MVPA appears more closely associated with pre/T2D risk compared to subjective measures, and there does not appear to be an additive effect of SED on pre/T2D risk after accounting for MVPA.

Associations between weight discrimination and metabolic health: A cross sectional analysis of middle aged adults

BACKGROUND

Concurrent with the recent rise in overweight and obesity, concerns with weight discrimination have arisen. Individuals who have experienced weight discrimination report a host of deteriorations related to physical and psychological health, which may co-exist with behaviours such as increased food consumption and decreases in physical activity that make weight management difficult. What remains less clear, however, is the extent to which metabolic health may be specifically affected, and how this may vary by setting and perceived intensity of the lifetime history of weight discrimination.

METHOD

To address this, a secondary data analysis was performed on 1365 participants from year 25 of the Coronary Artery Disease in Young Adults (CARDIA) study who were living with overweight and obesity. Descriptive statistics and logistic regression analyses were performed on the presence of metabolic syndrome, diabetes, and abdominal obesity, as well as their experience of the weight discrimination.

RESULTS

Prevalence of the metabolic syndrome, diabetes, and abdominal obesity was higher among those reporting low and high stress weight discrimination compared to those with no history of weight discrimination. In the adjusted analyses, weight discrimination was associated with a 65% greater likelihood for having metabolic syndrome, 85% greater likelihood of diabetes, and between a 2.5- and 3.9-times greater likelihood of abdominal obesity for low and high stress experiences, respectively.

CONCLUSION

Exposure to weight discrimination may worsen metabolic health, as characterized by higher rates of metabolic syndrome and abdominal obesity. These associations may be greater with levels of stress experienced from weight discrimination. Further longitudinal work is necessary to understand the temporal sequence, time lag, and any possible critical periods for weight discrimination on metabolic health.

The Associations between Blood and Urinary Concentrations of Metal Metabolites, Obesity, Hypertension, Type 2 Diabetes, and Dyslipidemia among US Adults: NHANES 1999-2016

Background

Heavy metals are well known to be associated with cancer outcomes, but its association with obesity and cardiometabolic risk outcomes requires further study.

Methods

Adult data from the National Health and Examination Survey (NHANES Continuous 1999-2016, n = 12,636 to 32,012) with data for blood or urinary metals concentrations and body mass index were used. The study aim was twofold: (1) to determine the association between heavy metals and obesity and (2) to examine the influence of heavy metals on the relationship between obesity and hypertension, type 2 diabetes, and dyslipidemia. Logistic regression was used to examine the main effects and interaction effects of metals and obesity for the odds of prevalent hypertension, type 2 diabetes, and dyslipidemia. Models were adjusted for age, gender, ethnicity, smoking status, physical active status, and poverty-income ratio, with additional adjustment for creatinine in models with the urinary measures of heavy metals. High-low concentration categories were defined by grouping metal quintiles with the most similar associations with obesity.

Results

Blood lead had a negative linear association with obesity (odds ratio (OR)  = 0.42, 95% confidence interval (CI) = 0.37-0.47). In those with obesity, high blood lead was associated with lower risk of prevalent dyslipidemia, while no association was found in those without obesity. The study observed a curvilinear relationship between urinary antimony and obesity with the moderate group having the highest odds of obesity (OR = 1.36, 1.16-1.59). However, the relationship between urinary antimony and prevalent hypertension and dyslipidemia risk was linear, positive, and independent of obesity. While not associated with prevalent obesity risk, high urinary uranium was associated with 30% (P=0.01) higher odds for prevalent type 2 diabetes.

Conclusions

The impact of environmental factors on obesity and health may be complex, and this study reinforces the heterogeneous relationship between various metals, obesity, and obesity-related metabolic diseases even at levels observed in the general population.

Effects of exercise modality on body composition and cardiovascular disease risk factors in adolescents with obesity: a randomized clinical trial

We compared the effects of aerobic exercise, resistance exercise, and combined aerobic and resistance exercise on total, regional subcutaneous adipose tissue (SAT) and visceral AT (VAT), skeletal muscle (SM), and biomarkers of cardiovascular disease in adolescents. Adolescents with overweight/obesity (N = 118; body mass index ≥ 85th percentile; age, 12-17 years) were randomized to 1 of the following groups for 6 months (3 days/week, 180 min/week): aerobic exercise (n = 38), resistance exercise (n = 40), or combined aerobic and resistance exercise (n = 40). After accounting for age, sex, and baseline value, there was a greater (P < 0.05) reduction in body weight in the aerobic exercise group compared with the resistance exercise group and the combined groups. There were reductions (P < 0.05) in total and regional SAT within the aerobic exercise group only, and the reductions in lower-body SAT were greater (P = 0.02) than the combined group. All groups had reductions (P < 0.01) in VAT, with no group differences. There were significant increases in total and regional SM mass in the resistance exercise and combined group, and not in the aerobic exercise group. Although all exercise modalities are effective in reducing VAT, aerobic exercise is superior at reducing total and regional SAT, but inferior for increasing SM in adolescents with obesity. Despite reductions in VAT, carotid-femoral pulse wave velocity and carotid intima-media thickness did not improve with either exercise. Clinicaltrials.gov identifier: NCT01938950. Novelty Regular exercise (180 min/week) is associated with reductions in visceral fat independent of exercise modality. Resistance exercise alone and combined resistance and aerobic exercise are similarly effective in increasing SM mass.

Associations between elevated kidney and liver biomarker ratios, metabolic syndrome and all-cause and coronary heart disease (CHD) mortality: analysis of the U.S. National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

We examined the relationship between ratios of select biomarkers of kidney and liver function on all-cause and coronary heart disease (CHD) mortality, both in isolation, and in combination with metabolic syndrome (MetS), among adults (20 + years, n = 10,604).

METHODS

Data was derived from the U.S. National Health and Nutrition Examination Survey (1999-2016) including public-use linked mortality follow-up files through December 31, 2015.

RESULTS

Select biomarker ratios of kidney (UACR or albuminuria and BUN-CR) and liver (AST-ALT and GGT-ALP) function in isolation and in combination with MetS were associated with all-cause and CHD mortality. Compared to individuals with neither elevated biomarker ratios nor MetS (HR = 1.00, referent), increased risk of all-cause mortality was observed in the following groups: MetS with elevated UACR (HR, 95% CI = 2.57, 1.99-3.33), MetS with elevated AST-ALT (HR = 2.22, 1.61-3.07), elevated UACR without MetS (HR = 2.12, 1.65-2.72), and elevated AST-ALT without MetS (HR = 1.71, 1.35-2.18); no other biomarker ratios were associated with all-cause mortality. For cause-specific deaths, elevated risk of CHD mortality was associated with MetS with elevated UACR (HR = 1.67, 1.05-2.67), MetS with elevated AST-ALT (HR = 2.80, 1.62-4.86), and elevated BUN-CR without MetS (HR = 2.12, 1.12-4.04); no other biomarker ratios were associated with CHD mortality.

CONCLUSION

Future longitudinal studies are necessary to examine the utility of these biomarker ratios in risk stratification for chronic disease management.

The association of sex and calendar month with changes in weight: A retrospective cohort study of a community-based weight management clinic

OBJECTIVE

To assess changes in weight by calendar month and sex in patients enrolled in a weight loss intervention.

METHODS

Adults participating in a lifestyle weight loss intervention at the Wharton Medical Clinic from January 1st, 2007 to July 4th, 2019 were examined (N = 19,153). A linear generalized estimating equation was used to examine the association between weight change (baseline, month 1, month 2) and calendar month with adjustment for age, sex and baseline body mass index. A first order interaction between sex and calendar was included to assess if the association between calendar month and weight loss differs by sex.

RESULTS

Patients lost 1.3 ± 2.0 kg (1.2 ± 1.8%) of their body weight per month. As compared to the mean monthly weight loss, patients lost slightly less weight in September (mean, 95% confidence interval (CI): -0.3, -0.4 to -0.2 kg) and slightly more weight in October (0.2, 0.1-0.3 kg). With adjustment for age, body mass index and calendar month, men lost 0.4 kg/month (95% CI: 0.3, 0.5 kg/month) than women. There were no other significant differences in the monthly weight change between men and women (sex*calendar month P-value = 0.24).

CONCLUSION

While there were slight differences in the amount of weight change achieved by patients in September, and October, it was not of a magnitude that is likely clinically relevant. In addition, men consistently lost more weight than women across all calendar months. Taken together, this suggest that calendar month is not associated with differences in weight loss for men and women enrolled in a structured weight management program.

Sequential diets and weight loss: Including a low-carbohydrate high-fat diet with and without time-restricted feeding

OBJECTIVE

The aims of this study were to assess the effectiveness of a low-carbohydrate high-fat (LCHF) diet with and without a time-restricted feeding (TRF) protocol on weight loss and participating in three sequential dietary interventions (standard calorie-deficit diet, LCHF, and LCHF + TRF) on weight loss outcomes.

METHODS

Data from 227 adults from the Wharton Medical Clinic (WMC) were analyzed using a unidirectional case crossover design. Data was imputed for 154 patients to create a pseudo-sample in which everyone participated in three dietary interventions: standard calorie restriction, LCHF, and LCHF + TRF.

RESULTS

Patients lost an average of 11.1 ± 1.3 kg (9.8 ± 1.1%) after three sequential dietary interventions (P < 0.0001). Patients lost a statistically significant amount of weight from the standard WMC, LCHF, and LCHF+TRF diets (P < 0.05). With and without adjustment for age, sex, body mass index at the start of the dietary protocol, and treatment time, patients lost a similar amount of weight regardless of the dietary intervention (P > 0.05). Approximately 78.6% of patients achieved ≥5% weight loss with at least one of the diets.

CONCLUSION

Patients can lose a similar amount of weight regardless of the diet they are following. Approximately 78.9% of patients achieved 5% weight loss with at least one of the diets and lost an average 11.1 kg (or 9.8%). This is nearly double what has been previously reported for one dietary intervention. Thus, participating in sequential diets may be associated with greater absolute weight loss, and likelihood of achieving a clinically significant weight loss.

An analysis of weight loss efforts and expectations in a Canadian Cohort: A retrospective medical chart review

The weight loss history and weight loss goals were examined in 4108 patients referred to a publicly funded evidence-based clinical weight management program using a retrospective chart review. The majority of patients were white females, aged of 50.1 ± 13.7 years and a BMI of 39.0 ± 7.5 kg/m² . Pregnancy was the most common reason for weight gain in women (17.7%) and while the reasons in men are more varied (injury, stress and medication: all ~5%). Over 50% of patients cited no specific reason for their weight gain. Self-directed diet and exercise were the most commonly used self-reported weight loss methods. Women were more likely to report using medication and bariatric surgical weight loss methods than men (P < .05), and only 5% of women and 12.8% men report never having tried to lose weight in the past. Patients had an ideal weight loss goal of 28.9% to 34.4%, which was similar to the patient's lowest reported adult weight. Approximately 70% of patients enrolling at the clinic had previously lost at least 4.5 kg (10 lb) one or more times and 16.7% lost weight at least 5 times in their life, but patient weight at enrolment was similar to their highest adult reported weight. Thus, most patients referred to this clinical weight management program have previously attempted self-directed diet and exercise weight loss. Patients were close to their highest adult weight and had very large weight loss goals, similar to what is typically achieved only by surgical intervention, despite having already had several bouts of weight loss.

Effects of Exercise on Resting Metabolic Rate in Adolescents with Overweight and Obesity

Background: We examined the effects of exercise training on resting metabolic rate (RMR), and whether changes in body composition are associated with changes in RMR in adolescents with overweight and obesity. Methods: One hundred forty adolescents (12-18 years, BMI ≥85th percentile) participated in randomized exercise trials (3-6 months) at UPMC Children's Hospital of Pittsburgh (18 control, 51 aerobic, 50 resistance, and 21 combined aerobic and resistance exercise). All participants had RMR assessments by indirect calorimetry after a 10-12 hour overnight fast, and body composition by magnetic resonance imaging and dual-energy X-ray absorptiometry. Results: There were no significant changes in RMR (kcal/day) between exercise groups vs. controls (p > 0.05). All exercise groups decreased visceral fat (-0.2 ± 0.02 kg; p < 0.05) compared to control. Increases in fat-free mass (FFM) were only seen in the combined group (2.3 ± 0.4 kg; p < 0.05), whereas increases in skeletal muscle mass were observed in both resistance (1.2 ± 0.2 kg; p < 0.05) and combined (1.5 ± 0.3 kg; p < 0.05) groups vs. control. Change in FFM, but not fat mass (FM), visceral fat, or skeletal muscle mass (p > 0.05), was a significant determinant of changes in RMR, independent of exercise modality (p = 0.04). Conclusion: Although exercise modality was not associated with changes in RMR, change in FFM, but not skeletal muscle or FM, was a significant correlate of changes in RMR in adolescents with overweight and obesity. Clinicaltrials.gov registration numbers: NCT00739180, NCT01323088, NCT01938950.

Association between metformin and physical activity with glucose control in adults with type 2 diabetes

Objective

To examine the combined association between metformin use and physical activity on HbA1c in adults with type 2 diabetes.

Research Design and Methods

Adults with type 2 diabetes from NHANES continuous survey (1999-2018, n = 6447) were classified as active and inactive based on self-reported engagement in moderate-to-vigorous or vigorous physical activity (MVPA or VigPA) and metformin use over the last month.

Results

There was a significant negative main effect of metformin usage on HbA1c levels, independent of whether individuals engaged in modest levels of MVPA or VigPA. Moreover, there was a higher prevalence of metformin users with a HbA1c < 6.5% than non-metformin users with no differences by activity status (36.1%-39.5% versus 24.9%-29.7%, respectively). There was a significantly lower HbA1c level (P = .007) and trend for a higher odds of having a HbA1c that achieved the clinical target of <7% (OR, 95% CI = 1.2, 1.0-1.4, P = .06) in the MVPA than non-MVPA group for only those not using metformin. For those using metformin, there was no difference in HbA1c levels by either MVPA or VigPA (both P > .05).

Conclusions

There appears to be independent benefits of metformin and regular physical activity on glucose control, but the impact of these two treatments are not necessarily additive. Based on this analyses, the benefit of physical activity on HbA1c levels in type 2 diabetes is likely more apparent in those not taking metformin, as compared to those who are.

No differences in the body fat after violating core bioelectrical impedance measurement assumptions

Objective

It is unclear to what degree acutely violating bioelectrical impedance analysis (BIA) measurement assumptions will alter the predicted percent fat mass (%FM) and whether this differs by sex or body mass index (BMI).

Methods

%FM was assessed under control, dehydration, exercise, water, food intake and non-voided bladder conditions with three BIA devices (Tanita: BC-418, TBF-314, & Omron HBF-306CN) for men (n = 23, age: 24.0 ± 5.2 years old) and women (n = 17, age: 22.5 ± 3.4 years old) separately.

Results

For all BIA devices, there were no differences in the %FM values between the control and the other conditions in men or women (− 1.9 to 0.4%, p > 0.05). Across the three devices and five conditions, 97% of %FM tests returned values within 5% of control (2 tests), and 86% of tests were within 2% of control despite violating an assumption. The errors were greatest with dehydration and women were more likely to have a %FM difference greater than 2% than men with dehydration using the hand-to-foot device (Tanita TBF-314: 59% versus 9%). There were no differences in %FM between control and the conditions when examined by BMI (overweight/obesity: − 2.8 to 0.1% and normal weight: − 1.7 to 0.5%; BMI*trial, p = 0.99).

Conclusion

%FM estimates were similar despite acutely violating the preliminary measurement BIA assumptions across a range of different BMIs. The minor variations in %FM are smaller than what would be expected with day-to-day variability or weight loss intervention but may be larger in women than men.

Separate and combined relationships for cardiorespiratory fitness and muscular strength with visceral fat and insulin sensitivity in adolescents with obesity

We examined the separate and combined associations for cardiorespiratory fitness (CRF) and muscular strength (MS) with total and regional fat, and insulin sensitivity (IS) in 204 adolescents (BMI ≥85th percentile, 12-18 years) at UPMC Children's Hospital of Pittsburgh. CRF was measured by maximum oxygen consumption during a graded treadmill test. MS was quantified by combining 1-repetition maximum test for the leg and bench press. Participants were stratified as having either high or low CRF and MS based on sex-specific median split. Both high CRF and high MS groups had lower (P < 0.05) total fat after adjustment for sex, Tanner stage and ethnicity than the low CRF and MS groups (Difference: 6.6, 2.6-9.6% and 5.4, 2.4-8.3%, respectively). High CRF, but not high MS, had lower visceral (67.5 versus 77.9 cm², P < 0.01) and intermuscular fat (3.6 versus 4.0 kg, P = 0.01) than the low CRF groups. Differences by CRF remained significant after adjustment for MS. High CRF, but not high MS, was associated (P < 0.05) with lower fasting glucose and higher IS after accounting for sex, Tanner stage and ethnicity than the low CRF group, and high CRF remained associated with these markers after adjustment for MS. High CRF is associated with lower total and regional fat, and higher IS after adjustment for MS. Novelty: CRF is associated with lower total fat, visceral and intermuscular fat, and higher insulin sensitivity adjusting for muscular strength. Muscular strength is not associated with regional body fat and insulin sensitivity after accounting for CRF.

Predictors of Weight Loss and Weight Gain in Weight Management Patients during the COVID-19 Pandemic

OBJECTIVE

To examine the associations between patient struggles, health, and weight management changes during the COVID-19 pandemic.

METHODS

585 patients attending a publicly funded clinical weight management program responded to an electronic survey.

RESULTS

Over half of the patients reported worsened overall health, mental health, physical activity, or diet during the pandemic. Approximately 30% of patients lost ≥3% of their body weight and 21% gained ≥3% of their body weight between March and July of the pandemic. Reports of social isolation was associated with increased odds for weight loss in women (OR = 2.0, 1.2-3.3), while low motivation (OR = 1.9, 1.0-3.7), depression (OR = 2.5, 1.0-6.3), and struggles with carbohydrate intake (OR = 2.1, 1.0-4.3) were associated with weight gain. Cooking more at home/eating less take out was associated with increased likelihood of weight loss (OR = 2.1, 1.1-3.9) and lower odds for weight gain (OR = 0.2, 0.1 to 0.97). Working from home was not associated with weight loss or weight gain (P > 0.6).

CONCLUSION

The COVID-19 pandemic is associated with certain factors that may facilitate weight loss and other factors that promote weight gain. Thus, depending on the patient experience during the pandemic, prevention of weight gain may be more appropriate than weight loss.

Assessing the utility of cardiorespiratory fitness, visceral fat, and liver fat in predicting changes in insulin sensitivity beyond simple changes in body weight after exercise training in adolescents

To examine the utility of changes in cardiorespiratory fitness (CRF) and body composition in response to exercise training in adolescents with obesity beyond simple measures of body weight change. This is a secondary analysis of our previously published randomized trials of aerobic, resistance, and combined training. We included 104 adolescents (body mass index (BMI) ≥85th percentile) who had complete baseline and post-intervention data for CRF, regional body fat, insulin sensitivity, and oral glucose tolerance. Associations between changes in body composition and CRF with cardiometabolic variables were examined adjusted for age, sex, Tanner stage, race, exercise group, and weight loss. At baseline, CRF, visceral fat and liver fat were correlated with insulin sensitivity with and without adjustment for BMI percentile. Training-associated changes in CRF, visceral fat, and liver fat were also correlated with insulin sensitivity changes, but not independent of body weight change. After accounting for body weight change, none of the body composition or CRF were associated with changes in insulin sensitivity, glucose tolerance, systolic blood pressure, or high-density lipoprotein cholesterol. Although CRF and body composition were strong independent correlates of insulin sensitivity at baseline, changes in CRF and visceral fat were not associated with changes in insulin sensitivity after accounting for body weight change. Clinicaltrials.gov registration nos.: NCT00739180, NCT01323088, NCT01938950. Novelty With exercise training, changes in body weight, CRF, visceral fat, and liver fat were correlated with changes in insulin sensitivity. Changes in body composition or CRF generally did not remain significant correlates of changes in insulin sensitivity after adjusting for body weight changes.

Changes in the prevalence of chronic conditions associated with abdominal obesity between 1999 and 2014

To examine the trends in chronic conditions after accounting for temporal differences in body mass index (BMI) and waist circumference (WC). Pooled cycles (1999-2014) of the U.S. National Health and Nutrition Examination Survey (NHANES) were analysed (n = 36 959). The models were adjusted for caloric intake, smoking, medications use and physical activity. The prevalence of diabetes increased in women with general or abdominal obesity (BMI*time; WC*time, P < .05), but there were no differences in men. For hypertension, independent of BMI, the prevalence was not different over time in both sexes (P > .05), whereas for a given WC, there was a decrease in the prevalence over time in women (WC*time, P = .05). For dyslipidemia, independent of BMI, the prevalence decreased in men, whereas for a given WC, there was a decrease in the prevalence in both sexes (P < .05). Over the same time frame, blood pressure, low-density lipoprotein and triglycerides decreased, while plasma glucose increased independent of general and abdominal obesity (P < .001). The relationship between obesity and chronic conditions has changed over time. There may be other changes that have altered how obesity is related with metabolic health markers over time. Further investigation is needed to better understand the current causes of chronic conditions.

Sex and Ethnic Differences in the Relationship between Changes in Anthropometric Measurements and Visceral Fat in Adolescents with Obesity

OBJECTIVE

To examine sex and ethnic differences in how baseline and changes in anthropometric measures relate with change in visceral fat with interventions in adolescents.

STUDY DESIGN

Black and white adolescents (n = 143: body mass index [BMI] ≥85th percentile, 12-18 years) who participated in intervention studies (3-6 months) were included and had assessments of anthropometric measures (weight, BMI, waist circumference, waist-to-hip ratio [WHR], and waist-to-thigh ratio) and visceral fat at L4-L5 by magnetic resonance imaging before and after interventions.

RESULTS

At baseline, all of the anthropometric measures were positively associated with visceral fat (P < .05), with weight, waist circumference, and WHR having the largest variance explained (model adjusted R² = 0.35-0.47 vs 0.32-0.35). Blacks had 11.5-23.3 cm² less visceral fat compared with whites for a given anthropometric value. Girls tended to have less visceral fat for a given anthropometric value, but the sex differences were not consistently significant (range: 0.7-12.9 cm²). Changes in waist circumference, BMI, and weight, but not WHR, remained significantly associated with changes in visceral fat. There were no sex differences, and much more minimal ethnic differences (<4.9 cm²).

CONCLUSIONS

At baseline, there are sex and ethnic differences in how anthropometric measures correlate with visceral fat. However, there were minimal sex and ethnic differences in how changes in anthropometric measures related with changes in visceral fat. Although all of the anthropometric measures were associated with visceral fat at baseline, waist circumference, BMI, and weight, but not WHR were associated with changes in visceral fat.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT00739180, NCT01323088, and NCT01938950.

Effectiveness of a Community-Based Weight Management Program for Patients Taking Antidepressants and/or Antipsychotics

OBJECTIVE

This study aimed to compare weight loss (WL) outcomes for patients taking antidepressants and/or antipsychotics with those not taking psychiatric medication.

METHODS

A total of 17,519 adults enrolled in a lifestyle WL intervention at the Wharton Medical Clinics in Ontario, Canada, were analyzed. Sex-stratified multivariable linear regression analysis was used to examine the association of taking antidepressants, antipsychotics, both, or neither with WL when adjusting for age, initial weight, and treatment time.

RESULTS

Twenty-three percent of patients were taking at least one psychiatric medication. Patients lost a significant amount of weight (P < 0.0001) regardless of psychiatric medication use. Women taking psychiatric medications lost a similar amount of weight as women who were not (P > 0.05). Conversely, men taking antidepressants lost only slightly less weight than men taking both classes or neither class of psychiatric medication (3.2 ± 0.3 kg vs. 5.6 ± 0.9 kg and 4.3 ± 0.1 kg; P < 0.05). However, taking psychiatric medications that cause weight gain was associated with similar significant decreases in weight as taking medications that are weight neutral or associated with WL for both sexes (P > 0.05).

CONCLUSIONS

Results of this study suggest that those who participate in a weight management program can lose significant amounts of weight regardless of psychiatric medication use.

Liraglutide 3.0 mg for the management of insufficient weight loss or excessive weight regain post-bariatric surgery

To assess the effectiveness of liraglutide 3.0 mg in post-bariatric surgery patients, and to determine whether this would differ based on the type of bariatric surgery. One hundred seventeen post-bariatric surgery patients from the Wharton Medical Clinic were analysed. Changes in weight while taking liraglutide 3.0 mg were examined for all patients, and by three types of bariatric surgery-Roux-en-Y gastric bypass, gastric banding and gastric sleeve. Patients primarily underwent Roux-en-Y gastric bypass (n = 53, 45.3%) or gastric banding (n = 50, 42.7%). Over 7.6 ± 7.1 months taking liraglutide 3.0 mg, patients lost a statistically significant amount of weight (-6.3 ± 7.7 kg, P < .05) regardless of the type of surgery they had (P > .05). This decrease in weight remained significant after 1-year of taking liraglutide 3.0 mg (P < .05). Nausea was the most prevalent side effect, reported by 29.1% patients. While options for excess weight management in post-bariatric surgery patients are limited, results of this study suggest that post-bariatric surgery patients can lose a significant amount of weight while taking liraglutide 3.0 mg regardless of the type of surgery they had. Further, similar to non-surgical populations, post-bariatric surgery patients taking liraglutide 3.0 mg may experience gastrointestinal side effects such as nausea and can continue to lose weight up to 1 year.

What Is the Role of Resistance Exercise in Improving the Cardiometabolic Health of Adolescents with Obesity?

Traditionally, individuals with obesity have been encouraged to participate in aerobic exercise for long-term weight management and improved obesity-related health outcomes. Recently, resistance exercise has become a popular mode of exercise among youth with obesity. However, to date, the literature is mixed as to whether resistance exercise training alone improves body weight, fat free mass, body composition, cardiovascular risk factors, or atherogenic lipoprotein profiles. The limited research in this area suggests potential sex differences in response to resistance training in youth. The literature is more consistent in demonstrating improvements in muscular fitness and insulin resistance independent of caloric restriction and weight loss. Although major health organizations recommend combining aerobic and resistance training, little research has examined the effects of their combination versus their individual effects, thus it is unclear whether their combination is associated with benefits that extend beyond those of either exercise modality alone. The purpose of this review is to examine the effects of resistance exercise on body composition and the health risk factors associated with cardiovascular disease and type 2 diabetes in youth with obesity.

Age- and sex- specific all-cause mortality risk greatest in metabolic syndrome combinations with elevated blood pressure from 7 U.S. cohorts

BACKGROUND

The association between metabolic syndrome (MetS) and all-cause mortality is well established but it is unclear if there are differences in mortality risk among the 32 possible MetS combinations. Hence, the purpose of this study is to evaluate the associations between different MetS combinations and its individual components with all-cause mortality, and to examine differences in the association by age and sex.

METHODS

A merged sample of 82,717 adults from 7 U.S. cohorts was used.

RESULTS

In our sample, MetS was present in 32% of men, 34% of women, 28% of younger adults (18-65 years) and 62% of older adults (>65 years) with 14,989 deaths over 14.6 ± 7.4 years of follow-up. Risk of all-cause mortality was higher in younger individuals with a greater number of MetS factors present, but in older adults having all 5 MetS factors was the only combination significantly associated with mortality. Regardless of age or sex, elevated blood pressure was the MetS factor most consistently present in MetS combinations that were significantly and most strongly associated with mortality. In fact, elevated blood pressure in the absence of other risk factors was significantly associated with mortality in men (HR, 95% CI = 1.56, 1.33-1.84), women (HR = 1.62, 1.44-1.81) and younger adults (HR = 1.61, 1.45-1.79). Conversely, waist circumference, glucose and triglycerides in isolation were not associated with mortality (p>0.05).

CONCLUSION

In a large U.S. population, different combinations of MetS components vary substantially in their associations with all-cause mortality. Men, women and younger individuals with MetS combinations including elevated blood pressure had stronger associations with greater mortality risk, with minimal associations between MetS and mortality risk in older adults. Thus, we suggest that future algorithms may wish to consider differential weighting of these common metabolic risk factors, particularly in younger populations.

Influence of Sex on the Changes in Regional Fat and Skeletal Muscle Mass in Response to Exercise Training in Adolescents with Obesity

BACKGROUND

We retrospectively examined the sex differences in the changes in (1) total fat, total and regional subcutaneous adipose tissue (SAT), visceral fat, and intermuscular fat and (2) total and regional skeletal muscle distribution in response to aerobic exercise (AE) or resistance exercise (RE) in adolescents with obesity.

METHODS

Twenty-eight boys and 27 girls with obesity (BMI ≥95th percentile, 12-18 years) were randomly assigned to 3-month interventions (180 minutes per week) of AE or RE. Changes in total and regional fat and skeletal muscle distribution were assessed by a whole-body magnetic resonance imaging.

RESULTS

After controlling for corresponding baseline values, age, and race, changes in body weight, BMI, BMI z-score, and waist circumference were similar between exercise groups (p > 0.05) and sexes (p > 0.05). There were no sex or exercise group differences in the reductions in total fat, total SAT, visceral fat, or intermuscular fat. With AE, boys had greater (p < 0.05) reductions in abdominal SAT as compared with girls. With RE, boys had greater (p < 0.05) increases in total, upper body, and abdominal skeletal muscle as compared with girls. Independent of exercise modality, the improvement in VO_2max was greater (p < 0.05) in boys than in girls. Independent of sex, the increase in muscular strength index was higher (p < 0.05) in the RE vs. AE group.

CONCLUSION

With the exception of abdominal SAT, there were no sex or exercise treatment differences in the reductions in total and regional fat. In response to RE, the increases in total and regional skeletal muscle were significantly greater in boys than in girls.

Effects of Exercise Modality on Insulin Resistance and Ectopic Fat in Adolescents with Overweight and Obesity: A Randomized Clinical Trial

OBJECTIVE

To examine whether a combined aerobic exercise and resistance exercise is more effective than either aerobic exercise or resistance exercise alone in improving insulin sensitivity and reducing total adiposity and ectopic fat in adolescents.

STUDY DESIGN

A total of 118 sedentary adolescents with overweight/obesity (body mass index >85th percentile, 12-17 years) were recruited from October 2013 through April 2017 at Children's Hospital of Pittsburgh. Participants were randomized to 1 of the following 6-month exercise groups (3 d/wk, 180 min/wk): aerobic exercise (n = 38), resistance exercise (n = 40), and combined aerobic exercise and resistance exercise (n = 40). The primary outcome was the change in insulin-stimulated glucose disposal by a 3-hour hyperinsulinemic-euglycemic clamp. The secondary outcomes were changes in liver fat by proton magnetic resonance spectroscopy and intermuscular adipose tissue by computed tomography.

RESULTS

Of the 118 participants randomized, 85 participants (72%) completed the study with 90% exercise attendance. Total adiposity reduced similarly in all groups (-2%, P < .05). After adjusting for age and sex, insulin-stimulated glucose disposal increased (P < .05) in all groups, with the increase in the aerobic exercise group being greater than the resistance exercise group (1.7 ± 0.1 vs 0.7 ± 0.1 mg/kg/min, P < .05) but not different from the combined group (1.2 ± 0.1 mg/kg/min). Liver fat was reduced (P < .05) in the aerobic exercise (-0.6%) and combined (-0.6%) groups but not in the resistance exercise group (-0.3%, P > .05). Intermuscular adipose tissue decreased (P < .05) similarly in all groups.

CONCLUSION

Combined aerobic exercise and resistance exercise and aerobic exercise alone are similarly beneficial in improving insulin sensitivity and reducing ectopic fat in adolescents with obesity.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01938950.

Lifetime risk of cardiometabolic mortality according to vitamin D status of middle and older-aged adults: NHANES III mortality follow-up

The predictive value of total 25-hydroxyvitamin D (25(OH)D, a biomarker of vitamin D status) in relation to lifetime risk of cardiometabolic mortality is not known. The purpose of this study was to determine the association between standardized and annualized total 25(OH)D levels and lifetime risk for cardiometabolic mortality in middle- to older-aged adults. In this study, we followed up 7958 participants in the Third National Health and Nutrition Examination Survey from 1988 to 1994 (NHANES III) until the occurrence of cardiometabolic death or attainment of 95 years of age (median follow-up 17.9 years, 1371 cardiometabolic-deaths). Lifetime risks were estimated according to recommended total 25(OH)D cutoffs by national guidelines, and a combination of total 25(OH)D status and traditional risk factor burden. We also explored variation in lifetime risk estimates by levels of body mass index (BMI). The results of this study showed that annualized total 25(OH)D <30 nmol/L was associated with high lifetime risk of cardiometabolic mortality (40%). Lifetime risks of cardiometabolic mortality were similar for annualized levels between 30-< 50 nmol/L, 50-< 75 nmol/L and ≥75 nmol/L (31-33%). Lifetime risk was highest among participants with annualized total 25(OH)D <30 nmol/L and ≥2 major traditional risk factors (45%), whereas lifetime risk was lowest among participants with annualized 25(OH)D ≥30 nmol/L and low-intermediate risk factors (28%). Lifetime risk estimates were similar across BMI categories. In conclusion, a single measurement of vitamin D deficiency (annualized levels <30 nmol/L) in middle- to older-aged adults is a strong predictor of high lifetime risk for cardiometabolic mortality, particularly among those with high burden of traditional risk factors.

Absolute Weight Loss, and Not Weight Loss Rate, Is Associated with Better Improvements in Metabolic Health

OBJECTIVE

To determine if the rate of weight loss (WL) is associated with metabolic changes independent of the absolute WL.

METHODS

WL and health changes were assessed in 11,281 patients attending a publicly funded clinical weight management program over a treatment period of 12.7 months. Early weight loss rate (WLR) in the first 3-6 months and overall WLR were categorized as Fast WLR (≥1 kg/wk), Recommended WLR (0.5 to 0.9 kg/wk), or Slow WLR (<0.5 kg/wk).

RESULTS

On average, patients attained a 6.6 ± 7.3 kg (5.8 ± 5.7%) WL over 12.8 ± 13.1 months. Prior to adjusting for covariates, patients with Fast WLR (-24.7 ± 13.4 kg) at 3-6 months had a greater overall WL as compared to those with Recommended WLR (-13.3 ± 8.7 kg) and Slow WLR (-5.0 ± 5.4 kg). Fast WLR also had greater improvements in the overall waist circumference and blood pressure than patients with Slow or Recommended WLR. However, after adjustment for absolute WL, Early and overall Recommended and Fast WLR did not differ in the changes in any of the health markers (P > 0.05). Conversely, the absolute WL sustained is significantly associated with changes in metabolic health independent of WLR (P < 0.001). Similar results were observed with WLR over the entire treatment period.

CONCLUSIONS

Faster rates of WL are associated with a greater absolute WL and larger improvements in waist circumference and blood pressure. However, after adjusting for the larger absolute WL sustained, early and overall faster WLR do not appear to have advantages for improving metabolic health markers. Thus, the absolute WL attained may be the most important factor for improving metabolic health.

The Association between Antihypertensive Medication Use and Blood Pressure Is Influenced by Obesity

Introduction

One in three US adults is living with obesity or hypertension, and more than 75% of hypertensive individuals are using antihypertensive medications. Therefore, it is important to examine blood pressure (BP) differences in populations that are using these medications with differing obesity status.

Aim

We examined whether BP attained when using various antihypertensive medications varies amongst different body mass index (BMI) categories and whether antihypertensive medication use is associated with differences in other metabolic risk factors, independent of BMI.

Methods

Adults with hypertension from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2014 were used (n=15,285). Linear regression analyses were used to examine the main effects and interaction between antihypertensive use and BMI.

Results

In general, users of antihypertensive medications had lower BP than those not taking BP medications (NoBPMed) (P < 0.05), whereby in women, the differences in systolic BP between angiotensin-converting-enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) users and NoBPMed were greater in those with obesity (ACE inhibitors: -14 ± 1 mmHg; ARB: -16 ± 1 mmHg) compared to normal weight individuals (ACE inhibitors: -9 ± 1 mmHg; ARB: -11 ± 1 mmHg) (P < 0.05). Diastolic BP differences between women ARB users and NoBPMed were also greatest in obesity (-5 ± 1 mmHg) (P < 0.05) whilst there were no differences in normal weight individuals (-1 ± 1 mmHg) (P>0.05). Furthermore, glucose levels and waist circumference in women were higher in those using ACE inhibitors compared to diuretics (P < 0.05).

Conclusion

ACE inhibitors and ARBs may be associated with more beneficial BP profiles in women with obesity, with no obesity-related BP differences for antihypertensive medication in men. However, there could be potential cardiometabolic effects for some antihypertensive medications that should be explored further.

Do moderate- to vigorous-intensity accelerometer count thresholds correspond to relative moderate- to vigorous-intensity physical activity?

We aimed to predict % maximal oxygen consumption at absolute accelerometer thresholds and to estimate and compare durations of objective physical activity (PA) among body mass index (BMI) categories using thresholds that account for cardiorespiratory fitness. Eight hundred twenty-eight adults (53.5% male; age, 33.9 ± 0.3 years) from the National Health and Nutrition Examination Survey 2003-2004 were analyzed. Metabolic equivalent values at absolute thresholds were converted to percentage of maximal oxygen consumption, and accelerometer counts corresponding to 40% or 60% maximal oxygen consumption were determined using 4 energy expenditure prediction equations. Absolute thresholds underestimated PA intensity for all adults; however, because of lower fitness, individuals with overweight and obesity work at significantly higher percentage of maximal oxygen consumption at the absolute thresholds and require significantly lower accelerometer counts to reach relative moderate and vigorous PA intensities compared with those with normal weight (P < 0.05). However, moderate-to-vigorous physical activity (MVPA) durations were shorter when using relative thresholds compared with absolute thresholds (in all BMI groups, P < 0.05), and they were shorter among individuals with obesity compared with those with normal weight when using relative thresholds (P < 0.05). Regardless of the thresholds used, a greater proportion of individuals with normal weight met the PA guideline of 150 min·week^-1 of MVPA compared with individuals with obesity (absolute: 21.3% vs 6.7%; Yngve: 4.0% vs 0.2%; Swartz: 10.7% vs 3.9%; Hendelman: 4.7% vs 0.2%; Freedson: 6.4% vs 0.5%; P < 0.05). Current absolute thresholds of accelerometry-derived PA may overestimate MVPA for all BMI categories when compared with relative thresholds that account for cardiorespiratory fitness. Given the large variability in our results, more work is needed to better understand how to use accelerometers for evaluating PA at the population level.

Metabolically healthy obesity, vitamin D, and all-cause and cardiometabolic mortality risk in NHANES III

BACKGROUND & AIMS

Previous studies assessing the prognosis of metabolically healthy obesity (MHO) have been limited by a lack of a harmonized definition of MHO phenotype. Furthermore, obesity is a risk factor for vitamin D deficiency and low vitamin D status has been associated with a higher risk of mortality; however, few studies have evaluated the joint association between vitamin D, metabolic health phenotype, and mortality risk. Using a harmonized definition, we investigated whether MHO is associated with subsequent all-cause and cardiometabolic mortality, and whether serum 25-hydroxyvitamin D [25(OH)D] modifies these associations.

METHODS

This study included participants aged ≥20 years from the Third National Health and Nutrition Examination Survey (NHANES III). MHO phenotype was defined as a combination of obesity (≥30 kg/m²) and zero component of metabolic syndrome. Multivariable Cox regression was used to assess the risk of mortality across metabolic phenotypes, and the joint association between metabolic phenotype and 25(OH)D. Fine and Gray regression was performed to account for competing risk events.

RESULTS

Among 11,333 participants, a total of 2980 deaths (937 cardiometabolic death outcomes) occurred during a median follow-up of 19.1 years. In the absence of any metabolic abnormality, obesity (MHO) was not associated with a higher risk of all-cause (hazard ratio [HR], 0.89 [95% CI, 0.52-1.51]) or cardiometabolic mortality (cause-specific HR, 1.21 [95% CI 0.33-4.46]). Similar results were obtained from competing risk analysis. No significant differences in average 25(OH)D levels were observed between MHO and non-MHO participants; however, there was a significant interaction between metabolic health phenotype and serum 25(OH)D in relation to cardiometabolic mortality such that levels of serum 25(OH)D < 50 nmol/L were associated with increased risk of cardiometabolic mortality, particularly in participants within the normal-weight and obese BMI ranges.

CONCLUSIONS

Our results support the hypothesis that MHO phenotype is a benign health condition. Vitamin D deficiency may exacerbate the risk of cardiometabolic death outcomes associated with metabolic dysfunction in normal weight and obese individuals. Further research is warranted to validate our findings.

Waist circumference at five common measurement sites in normal weight and overweight adults: which site is most optimal?

The aim of this study was to determine (i) if adults would measure their own waist circumference (WC), (ii) which WC site(s) are the most intuitive and easy to measure and (iii) if measurement accuracy and association between WC and blood pressure differs across five measurement sites. Participants (n = 198) measured their WC first with no instruction and then using visual instructions for the iliac crest, last rib, midpoint, minimal waist and umbilicus. Without instruction, men most commonly measured their WC at the umbilicus and iliac crest, while women measured their WC at the umbilicus and minimal WC. Both men and women reported the minimal waist and umbilicus to be moderately easier to self-measure compared to the other sites (P < 0.05). Prevalence of abdominal obesity varied significantly by gender and measurement site, especially for females (normal weight: 0-18%; overweight: 51-79%). Measurement site did not influence accuracy of WC self-measurement or the association between WC and blood pressure (P > 0.05). A universal WC landmark is needed. From these results, there does not appear to be a clear clinical advantage in terms of blood pressure or practical advantage of measuring one WC site over another. However, the umbilicus may be the most intuitive and easy to measure.

Association between cardiorespiratory fitness and metabolic risk factors in a population with mild to severe obesity

Background

Previous literature suggests the beneficial effects of fitness on abdominal obesity may be attenuated in obesity and abolished in severe obesity. It is unclear whether the beneficial association between fitness and health is similarly present in those with mild and severe obesity.

Methods

Patients from the Wharton Medical Clinic (n = 853) completed a clinical examination and maximal treadmill test. Patients were categorized into fit and unfit based on age- and sex-categories and body mass index (BMI) class (mild: ≤ 34.9 kg/m², moderate: 35–39.9 kg/m² or severe obesity: ≥ 40 kg/m²).

Results

Within the sample, 41% of participants with mild obesity had high fitness whereas only 25% and 11% of the participants with moderate and severe obesity, respectively, had high fitness. BMI category was independently associated with most of the metabolic risk factors, while fitness was only independently associated with systolic blood pressure and triglycerides (P < 0.05). The prevalent relative risk for pre-clinical hypertension, hypertriglyceridemia and hypoalphalipoproteinemia and pre-diabetes was only elevated in the unfit moderate and severe obesity groups (P < 0.05), and fitness groups were only significantly different in their relative risk for prevalent pre-clinical hypertension within the severe obesity group (p = 0.03). High fitness was associated with smaller waist circumferences, with differences between high and low fitness being larger in those with severe obesity than mild obesity (Men: P = 0.06, Women: P = 0.0005).

Conclusions

Thus, in contrast to previous observations, the favourable associations of having high fitness and health may be similar if not augmented in individuals with severe compared to mild obesity.

Visceral fat is associated with the racial differences in liver fat between black and white adolescent boys with obesity

OBJECTIVE

We examined whether racial differences in liver fat are associated with the differences in abdominal fat distribution or cardiorespiratory fitness (CRF).

METHODS

Participants included 57 black and white obese boys (12-18 years). Total and abdominal fat was measured by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging, respectively. CRF was measured using a maximal graded treadmill test with the use of standard open-circuit spirometry techniques until volitional fatigue. Liver fat was measured using a 3T proton magnetic resonance spectroscopy. Fatty liver was defined as having liver fat ≥5%.

RESULTS

In the sample, 16.1% of black boys and 30.8% of white boys had fatty liver. Liver fat was associated (P ≤ .05) with body mass index (BMI) percentile (r = 0.28), total fat (r = 0.31), waist circumference (r = 0.38), visceral fat (r = 0.62), abdominal subcutaneous adipose tissue (r = 0.30), and CRF (r = -0.27) adjusting for age and race. White boys had greater liver fat than black boys with adjustment for age and differences in BMI percentile or CRF, but not with waist circumference or visceral fat (P > .05). In a model with age, ethnicity, total body fat, fat-free mass, visceral fat, abdominal subcutaneous fat, and CRF, visceral fat was the only factor to be independently associated with increased odds of having fatty liver (OR = 1.12; 95% CI: 1.04-1.21; P = .003).

CONCLUSION

The racial disparities in liver fat between obese black vs white adolescents are explained, in part, by differences in visceral fat.

Trends in medication use by body mass index and age between 1988 and 2012 in the United States

Objective

Whether the increase in prescription medication use over time differs by age and obesity status is unclear.

Method

National Health and Nutrition Examination Survey (NHANES) between 1988 and 2012 was analyzed (n = 57,543).

Findings

Increased medication use over time was seen in older individuals of all body mass index (BMI) classes, with the most prominent increase in those with obesity (p<0.001). For example, older men (≥65y) with obesity took 3.1 more medications between 1988 and 2012 versus 1.5 for normal weight older men. There were minimal differences in medication use over time in younger individuals. In men, the odds of taking antihypertensives, lipid-lowering medication, antidiabetics, and antidepressants increased with age, time and BMI wherein the association between age and medication use was magnified over time (age*time, p<0.05). In women, older women with overweight or obesity had a greater increase in the likelihood of antihypertensives and antidiabetics medication over time (BMI*time, p>0.05).

Conclusion

Older individuals of all BMI classes may be driving the increase in medication use over time. However, the rise in the likelihood of taking cardiometabolic medications over time was generally not different between those with or without obesity in men with some increases seen in older women. Further research may be required to assess accessibility and barriers to medication use among certain demographics.

The readiness and motivation interview for families (RMI-Family) managing pediatric obesity: study protocol

BACKGROUND

Experts recommend that clinicians assess motivational factors before initiating care for pediatric obesity. Currently, there are no well-established clinical tools available for assessing motivation in youth with obesity or their families. This represents an important gap in knowledge since motivation-related information may shed light on which patients might fail to complete treatment programs. Our study was designed to evaluate the measurement properties and utility of the Readiness and Motivational Interview for Families (RMI-Family), a structured interview that utilizes a motivational interviewing approach to (i) assess motivational factors in youth and their parents, and (ii) examine the degree to which motivation and motivation-related concordance between youth and parents are related to making changes to lifestyle habits for managing obesity in youth.

METHODS

From 2016 to 2020, this prospective study will include youth with obesity (body mass index [BMI] ≥97th percentile; 13-17 years old; n = 250) and their parents (n = 250). The study will be conducted at two primary-level, multidisciplinary obesity management clinics based at children's hospitals in Alberta, Canada. Participants will be recruited and enrolled after referral to these clinics, but prior to initiating clinical care. Each youth and their parent will complete the RMI-Family (~1.5 h) at baseline, and 6- and 12-months post-baseline. Individual (i.e., youth or parent) and family-level (i.e., across youth and parent) responses to interview questions will be scored, as will aspects of interview administration (e.g., fidelity to motivational interviewing tenets). The RMI-Family will also be examined for test-retest reliability. Youth data collected at each time point will include demography, anthropometry, lifestyle habits, psychosocial functioning, and health services utilization. Cross-sectional and longitudinal associations between individual and family-level interview scores on the RMI-Family and these clinical measures will be examined.

DISCUSSION

As a measurement tool drawing on family-centered care and motivational interviewing, the RMI-Family was designed to increase understanding of the role of motivational factors in pediatric obesity management, allowing healthcare providers and policymakers to manage pediatric obesity more effectively and efficiently. Findings will help to create an innovative, tailored model of health care delivery that uses resources judiciously and is designed to best meet families' needs.

The associations of resting metabolic rate with chronic conditions and weight loss

The aim of this study was to examine the associations between baseline and changes in resting metabolic rate (RMR) with chronic condition(s) and weight loss (WL). Sex stratified analysis was undertaken on 393 adults from the Wharton Weight Management Clinics. The association between baseline RMR and WL was examined adjusting for age, BMI, ethnicity and treatment time. The association between changes in RMR (ΔRMR) and WL was also examined adjusting for baseline RMR and above covariates. Models were further adjusted for high glucose, triglycerides, blood pressure, low-density lipoprotein (LDL) and low high-density lipoprotein (HDL). While men (6.0 ± 8.6 kg) and women (5.6 ± 8.3 kg) had significant WL throughout the intervention, their measured decreases in RMR (-48 ± 322 kcal and -5 ± 322 kcal, respectively) were non-significant (P > 0.05). Individuals with a high blood pressure had a higher baseline RMR and women with a high LDL had a lower baseline RMR than those without the chronic condition (P < 0.05). Regardless of sex, WL was not significantly associated with baseline RMR or ΔRMR (P > 0.05) in both models. Participants with a low baseline RMR do not appear to be at a disadvantage for WL. Further, WL can occur without decreases in RMR in populations with high levels of obesity and obesity-related comorbidities.

Waist circumference is associated with liver fat in black and white adolescents

We examined whether waist circumference (WC) is associated with liver fat in black and white adolescents. Liver fat was measured using a 3T proton magnetic resonance spectroscopy (¹H-MRS) in 152 overweight/obese adolescents (94 black and 58 white, body mass index (BMI) ≥85th percentile, aged 12-18 years) without liver diseases or diabetes. WC was measured at the last rib. Total and visceral adipose tissue (VAT) were measured by dual-energy X-ray absorptiometry and magnetic resonance imaging, respectively. The proportion of fatty liver (defined as liver fat ≥5.0% by ¹H-MRS) was lower (P < 0.01) in black adolescents (5.3%) compared with their white peers (24.1%). Despite similar age, BMI, WC, and total adiposity (%), black adolescents had lower (P < 0.01) VAT (59.0% vs. 81.3 cm²), liver fat (1.6% vs. 3.5%), and alanine aminotransferase (17.2 vs. 22.0 IU/L) compared with their white peers. Independent of race, WC was associated with liver fat (black, r = 0.43; white, r = 0.64) in a similar magnitude to the association between VAT and liver fat (black, r = 0.44; white, r = 0.51) and these findings remained significant after controlling for age, sex, Tanner stage, and total adiposity. In blacks, WC and sex (male) were independent (P < 0.01) predictors of liver fat, explaining 17.1% and 5.6% of the variance, respectively, while in whites WC was the single best predictor, explaining 40.8% of the variance in liver fat. These findings suggest that enlarged WC is a marker of increased liver fat in overweight/obese white and black adolescents.

Calorie Estimation in Adults Differing in Body Weight Class and Weight Loss Status

PURPOSE

Ability to accurately estimate calories is important for weight management, yet few studies have investigated whether individuals can accurately estimate calories during exercise or in a meal. The objective of this study was to determine if accuracy of estimation of moderate or vigorous exercise energy expenditure and calories in food is associated with body weight class or weight loss status.

METHODS

Fifty-eight adults who were either normal weight (NW) or overweight (OW), and either attempting (WL) or not attempting weight loss (noWL), exercised on a treadmill at a moderate (60% HRmax) and a vigorous intensity (75% HRmax) for 25 min. Subsequently, participants estimated the number of calories they expended through exercise and created a meal that they believed to be calorically equivalent to the exercise energy expenditure.

RESULTS

The mean difference between estimated and measured calories in exercise and food did not differ within or between groups after moderate exercise. After vigorous exercise, OW-noWL overestimated energy expenditure by 72% and overestimated the calories in their food by 37% (P < 0.05). OW-noWL also significantly overestimated exercise energy expenditure compared with all other groups (P < 0.05) and significantly overestimated calories in food compared with both WL groups (P < 0.05). However, among all groups, there was a considerable range of overestimation and underestimation (-280 to +702 kcal), as reflected by the large and statistically significant absolute error in calorie estimation of exercise and food.

CONCLUSIONS

There was a wide range of underestimation and overestimation of calories during exercise and in a meal. Error in calorie estimation may be greater in overweight adults who are not attempting weight loss.

Association between Sleep Habits and Metabolically Healthy Obesity in Adults: A Cross-Sectional Study

Higher body mass index (BMI) increases the risk of cardiometabolic diseases, but nearly a third of the people living with obesity (BMI: ≥30 kg/m²) are metabolically healthy (MHO). Extreme sleep durations and poor sleep quality are associated with higher bodyweight and cardiometabolic dysfunction, but the full extent to which sleep habits may help differentiate those with MHO versus metabolically abnormal obesity (MAO) is not yet known. Data from the U.S. National Health and Nutritional Examination Survey 2005-08 was used (BMI: ≥30 kg/m²; ≥20 y; N = 1,777). The absence of metabolic syndrome was used to define MHO. Those with MHO tended to be younger, female, Non-Hispanic Black, never smokers, more physically active, and with less physician diagnosed sleep disorders than MAO. Neither sleep duration nor overall sleep quality was related to MHO in crude or multivariable adjusted analyses; however, reporting "almost always" to having trouble falling asleep (OR (95% CI): 0.40 (0.20-0.78)), waking up during the night (0.38 (0.17-0.85)), feeling unrested during the day (0.35 (0.18-0.70)), and feeling overly sleepy during the day (0.35 (0.17-0.75)) was related to lower odds of MHO. Selected sleep quality factors, but not sleep quantity or overall sleep quality, are associated with the MHO phenotype.

Accelerometer thresholds: Accounting for body mass reduces discrepancies between measures of physical activity for individuals with overweight and obesity

The objective of this study was to explore whether accelerometer thresholds that are adjusted to account for differences in body mass influence discrepancies between self-report and accelerometer-measured physical activity (PA) volume for individuals with overweight and obesity. We analyzed 6164 adults from the National Health and Nutrition Examination Survey between 2003-2006. Established accelerometer thresholds were adjusted to account for differences in body mass to produce a similar energy expenditure (EE) rate as individuals with normal weight. Moderate-, vigorous-, and moderate- to vigorous-intensity PA (MVPA) durations were measured using established and adjusted accelerometer thresholds and compared with self-report. Durations of self-report were longer than accelerometer-measured MVPA using established thresholds (normal weight: 57.8 ± 2.4 vs 9.0 ± 0.5 min/day, overweight: 56.1 ± 2.7 vs 7.4 ± 0.5 min/day, and obesity: 46.5 ± 2.2 vs 3.7 ± 0.3 min/day). Durations of subjective and objective PA were negatively associated with body mass index (BMI) (P < 0.05). Using adjusted thresholds increased MVPA durations, and reduced discrepancies between accelerometer and self-report measures for overweight and obese groups by 6.0 ± 0.3 min/day and 17.7 ± 0.8 min/day, respectively (P < 0.05). Using accelerometer thresholds that represent equal EE rates across BMI categories reduced the discrepancies between durations of subjective and objective PA for overweight and obese groups. However, accelerometer-measured PA generally remained shorter than durations of self-report within all BMI categories. Further research may be necessary to improve analytical approaches when using objective measures of PA for individuals with overweight or obesity.

The association between obesity and self-reported sinus infection in non-smoking adults: a cross-sectional study

The aim of this article was to examine the associations between having had a sinus infection (SI) and BMI and physical activity (PA), diet quality, stress and/or sleep. A total of 2915 adults from the National Health and Nutrition Examination Survey 2005-2006 were examined. Logistic regression analysis was used to examine the association between having had an SI with BMI and PA, diet quality, stress or sleep. As these factors are known to influence one another, a fully adjusted model with PA, diet quality, stress and sleep was also constructed to examine their independent associations with having had an SI. Overall, 15.5 ± 1.2% of the population report having had an SI in the past year. In all models, individuals with obesity were approximately twice as likely to have had an SI compared to those of normal weight (P < 0.05). While PA and diet quality were not significantly associated with having had an SI (P > 0.05), individuals with stress and sleep troubles were also twice as likely to have had an SI (P < 0.05) independent of BMI. In the fully adjusted model, only the associations for BMI and sleep troubles remained significant (P < 0.05). Results from this study suggest that obesity and sleep troubles, but not PA, quality of diet and stress, are associated with having had an SI. As interactions exist between obesity, immune system factors and exposure to infectious disease(s), more research is necessary to understand the directionality of these relationships.

Aspartame intake is associated with greater glucose intolerance in individuals with obesity

This study examined whether sucrose, fructose, aspartame, and saccharin influences the association between obesity and glucose tolerance in 2856 adults from the NHANES III survey. Aspartame intake significantly influenced the association between body mass index (BMI) and glucose tolerance (interaction: P = 0.004), wherein only those reporting aspartame intake had a steeper positive association between BMI and glucose tolerance than those reporting no aspartame intake. Therefore, consumption of aspartame is associated with greater obesity-related impairments in glucose tolerance.

Interest, views and perceived barriers to bariatric surgery in patients with morbid obesity

The objective of the study was to assess the interest, views and patient-perceived barriers to bariatric surgery among surgery-eligible patients. Surveys were completed at a weight management clinic and local hospital in Ontario, Canada. Patients were ≥18 years of age with a body mass index (BMI) >40 kg m(-2) or BMI > 35 kg m(-2) with ≥1 comorbidity. The sample included 105 participants, 73.3% female, with a mean BMI of 46.6 ± 7.1 kg m(-2) . Only 33.3% of participants were interested in surgery; 50.5% of participants were not interested and 16.2% had mixed feelings. Participants identified risks (69.5%) and side effects (57.1%) as significant surgical barriers. Interested participants were more likely to perceive themselves as obese, were unhappy with their current weight loss method and were less likely to fear surgery (P < 0.05). The prevalence of comorbidities was not different by surgical interest (P = 0.17). Despite the effectiveness of bariatric surgery, the majority of qualified patients are not interested in surgery mainly due to the perceived risk of surgery in general and satisfaction with current non-surgical weight loss efforts. The self-perception of obesity, as opposed to medical comorbidities, may be a stronger driver of the decision to have bariatric surgery. It is unclear if patients are aware of the effectiveness of bariatric surgery to help improve comorbidities or if bariatric surgery is perceived as being more cosmetic in nature.

Differences in weight change trajectory patterns in a publicly funded adult weight management centre

Objective

To describe differences in weight loss (WL) trajectory patterns at a publicly funded clinical weight management centre.

Methods

Groups with differences in the attainment of a 5% total body WL and percentage WL patterns over time were identified in 7,121 patients who attended a physician lead multi‐disciplinary clinical lifestyle weight management that predominantly focused on education and diet counselling. Resultant health differences were examined.

Results

Patients had 3.2 ± 6.3%WL with 35% of patients achieving and maintaining a 5%WL. Half of these patients achieved the 5%WL within 6 months, while the other half had a more gradual approach. Another 10% achieved 5%WL, but regained weight after 6 months. There were seven distinct WL patterns identified: LargeWL (Mean WL: 21.2 ± 8.1%; Probability of group membership (PGM): 2.4%), ModerateWL (15.1 ± 5.1%WL; 5.4%PGM), SlowWL (6.7 ± 3.2%WL; 20.1%PGM) and MinimalWL (2.4 ± 2.2%WL; 34.6%PGM), WL Regain (9.4 ± 3.5%WL; 8.2%PGM), Weight Stable (1.2 ± 3.2%WL; 28.5%PGM) and Weight Gain (18.4 ± 11.2%WG; 0.8%PGM) groups. Improvements in blood pressure, lipids and glucose were generally related to the magnitude of WL achieved more than the pattern or speed of WL.

Conclusions

There are large differences in the absolute WL attained and the pattern of WL during a publicly funded weight management program. Changes in clinical health markers appear to be more strongly related with the absolute WL attained as opposed to patterns of weight change. © 2016 The Authors. Obesity Science & Practice published by John Wiley & Sons Ltd, World Obesity and The Obesity Society.

Predictors of early attrition and successful weight loss in patients attending an obesity management program

Background

Our objective was to identify factors that are independently associated with early attrition and successful weight loss (WL) in an obesity-management program.

Methods

Participants were 9,498 patients enrolled in treatment at the Wharton Weight Management Clinic for at least 6 months. Predictors of early attrition (<6 months) and successful WL (≥5 %) were analyzed using relative risk (RR) in men and women separately. Pearson’s correlation was used to determine the relationship between WL and treatment time Weight loss and attrition analysis was restricted to patients who had more than two visits (n = 5415).

Results

Older individuals had lower early attrition (RR Range:0.74–0.92, P < 0.05) and greater WL success (RR Range:1.40–1.65, P < 0.05) than younger individuals. Males with hypertension and females with depression had greater early attrition (RR Range:1.09–1.20, P < 0.05) and lower WL success (RR Range:0.48–0.57, P < 0.05) than those without these health conditions. Males with lower education had greater early attrition (RR = 1.11[1.03–1.19]) than males with higher education, but did not differ in WL. Females who smoked had greater early attrition (RR = 1.06[1.01–1.11]) than females who did not smoke, but did not differ in WL. Ethnicity was not related to early attrition, however, females of Black and Other ethnicities had lower WL success compared to White females (RR Range:0.58–0.74, P < 0.05). After adjusting for treatment time, all above associations were no longer significant and treatment time remained as the only independent predictor of WL success (P < 0.0001).

Conclusion

As WL is positively and independently related with treatment time, individuals at risk for early attrition may need alternative treatment options, in order to improve patient retention and improve WL success.