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.