Ronald K. Evans

Becoming Physically Active After Bariatric Surgery is Associated With Improved Weight Loss and Health-related Quality of Life

The purpose of this study was to determine whether pre‐ to postoperative increases in physical activity (PA) are associated with weight loss and health‐related quality of life (HRQoL) following bariatric surgery. Participants were 199 Roux‐en‐Y gastric bypass (RYGB) surgery patients. The International Physical Activity Questionnaire (IPAQ) was used to categorize participants into three groups according to their preoperative and /1‐year postoperative PA level: (i) Inactive/Active (<200‐min/week/≥200‐min/week), (ii) Active/Active (≥200‐min/week/≥200‐min/week) and (iii) Inactive/Inactive (<200‐min/week/<200‐min/week). The Medical Outcomes Study Short Form‐36 (SF‐36) was used to assess HRQoL. Analyses of covariance were conducted to examine the effects of PA group on weight and HRQoL changes. Inactive/Active participants, compared with Inactive/Inactive individuals, had greater reductions in weight (52.5 ± 15.4 vs. 46.4 ± 12.8 kg) and BMI (18.9 ± 4.6 vs. 16.9 ± 4.2 kg/m2). Weight loss outcomes in the Inactive/Active and Active/Active groups were similar to each other. Inactive/Active and Active/Active participants reported greater improvements than Inactive/Inactive participants on the mental component summary (MCS) score and the general health, vitality and mental health domains (P < 0.01). Although the direction of causation is not clear, these findings suggest that RYGB patients who become active postoperatively achieve weight losses and HRQoL improvements that are greater than those experienced by patients who remain inactive and comparable to those attained by patients who stay active. Future randomized controlled trials should examine whether assisting patients who are inactive preoperatively to increase their PA postoperatively contributes to optimization of weight loss and HRQoL outcomes.

Prevalence of the metabolic syndrome among obese adolescents enrolled in a multidisciplinary weight management program: clinical correlates and response to treatment.

OBJECTIVE The aim of this study was to determine the prevalence of the metabolic syndrome at baseline and after 6 months of lifestyle modification among obese adolescents referred to a multidisciplinary weight management program. METHODS A total of 165 obese adolescents were evaluated at baseline, and measurements were repeated in 57 subjects who completed 6 months of the program. Metabolic syndrome was defined as having three or more of the following: a body mass index (BMI) >97(th) percentile, hypertension, low high-density lipoprotein cholesterol (HDL-C), hypertriglyceridemia, and impaired fasting glucose (IFG). RESULTS The prevalence of a BMI >97(th) percentile, hypertension, hypertriglyceridemia, low HDL-C, and IFG was 92.7, 54.5, 29.1, 26.7, and 2.4%, respectively. The prevalence of the metabolic syndrome at baseline was 30.3%. After 6 months of lifestyle modification, BMI z scores, percent body fat, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) decreased significantly from baseline; however, there was no significant change in the number of subjects demonstrating >or=three criteria of the metabolic syndrome. CONCLUSIONS Approximately one third of the study subjects met the criteria of the metabolic syndrome, emphasizing the growing concern for the future development of premature cardiovascular disease in this high-risk population. Our data suggest that new strategies for lifestyle modification may be needed to improve cardiovascular risk factors significantly among adolescents with obesity.

Evaluation of a 6-month multi-disciplinary healthy weight management program targeting urban, overweight adolescents: Effects on physical fitness, physical activity, and blood lipid profiles

This study evaluated preliminary physical fitness, physical activity, and blood lipid profile data obtained from overweight adolescents upon enrolling in a healthy weight management program and following 6 months of program participation. One hundred and sixty-eight participants (13.4+/-1.8 years, 37.9+/-8.3 kg/m(2), 59.5% female and 76.2% African-American) enrolled in the program. The intervention addressed factors related to nutrition, physical activity, and other behaviors related to weight management. Sixty-four participants (38.1%) completed 6 months of program participation. While there was no significant reduction in body mass or body mass index (BMI), BMI z-score was reduced by 1.2% (p < 0.05), cardiorespiratory fitness was increased by 10.8% (p = 0.001), body fat percentage was reduced by 2.6% (p = 0.001), total cholesterol was reduced by 7.2% (p < 0.001), and low density lipoprotein (LDL-C) was reduced by 8.4% (p < 0.001) at 6 months. Continued development and evaluation of programs designed to prevent and treat child and adolescent overweight is warranted to address this major public health issue.

Psychological stress during exercise: immunoendocrine and oxidative responses

The purpose of this study was to examine the changes in catecholamines (epinephrine [EPI] and norepinephrine [NE]), interleukin-2 (IL-2) and a biomarker of oxidative stress (8-isoprostane) in healthy individuals who were exposed to a dual challenge (physical and psychological stress). Furthermore, this study also examined the possible relationships between catecholamines (NE and EPI) and 8-isoprostane and between IL-2 and 8-isoprostane following a combined physical and psychological challenge. Seven healthy male subjects completed two experimental conditions. The exercise-alone condition (EAC) consisted of cycling at 60% VO2max for 37 min, while the dual-stress condition (DSC) included 20 min of a mental challenge while cycling. DSC showed greater EPI and 8-isoprostane levels (significant condition by time interaction). NE and IL-2 revealed significant change across time in both conditions. In addition, following dual stress, EPI area-under-the-curve (AUC) demonstrated a positive correlation with NE AUC and IL-2 AUC. NE AUC was positively correlated with IL-2 AUC and peak 8-isoprostane, and peak IL-2 was positively correlated with peak 8-isoprostane in response to a dual stress. The potential explanation for elevated oxidative stress during dual stress may be through the effects of the release of catecholamines and IL-2. These findings may further provide the potential explanation that dual stress alters physiological homeostasis in many occupations including firefighting, military operations and law enforcement. A greater understanding of these responses to stress can assist in finding strategies (e.g. exercise training) to overcome the inherent psychobiological challenges associated with physically and mentally demanding professions.

Stress hormones and immunological responses to a dual challenge in professional firefighters.

The purpose of this study was to examine the changes in heart rate (HR), catecholamines (norepinephrine [NE] and epinephrine [EPI]), pro-inflammatory cytokines (interleukin-2 [IL-2] and interleukin-6 [IL-6]), and lymphocytes (CD8+ and CD56+) in firefighters exposed to a decision-making challenge (firefighting strategies and tactics drill) while participating in moderate intensity exercise. Nine professional male firefighters participated in two counterbalanced exercise conditions on a cycle ergometer: (1) 37 min of cycle ergometry at 60% VO(2max) (exercise alone condition ; EAC) and (2) 37 min of cycle ergometry at 60% VO(2max) along with 20 min of a computerized firefighting strategy and tactics decision-making challenge (firefighting strategy condition; FSC). FSC elicited significantly greater HR, NE, EPI, and IL-2 when compared to EAC. These elevations may suggest that the addition of a mental challenge to physical stress can alter the hormonal and immunological responses during firefighting. In addition, this evidence provides insight into the possible mechanisms that explain the link between physical activity, psychological stress, and stress-related diseases.

Six-Month Dietary Changes in Ethnically Diverse, Obese Adolescents Participating in a Multidisciplinary Weight Management Program

This study’s objective was to examine dietary and metabolic changes in obese adolescents who completed 6 months of participation in an outpatient multidisciplinary weight management program (N = 67). Participants (75% African American, 66% female, mean age = 13.7 years) completed 24-hour dietary recalls and underwent measurement of anthropometrics and fasting blood lipid parameters at baseline and after 6 months of participation. General linear models suggested that participants significantly reduced total energy, total fat, saturated fat, carbohydrate, sodium, and sugar intakes, and increased fiber and fruit and vegetable intake (P < .05). Gender-stratified models showed differences in fruit/vegetable intake, percentage calories from fat, sodium, and dietary cholesterol intakes by gender. Significant improvements in body mass index percentile and lipid profiles were also found, lending objective support to the dietary changes participants made. Findings suggest that participation in this multidisciplinary treatment helped participants make behaviorally based dietary changes, which were associated with improved dietary intakes and health status.

Initiation and progression of physical activity after laparoscopic and open gastric bypass surgery.

This study compared postoperative physical activity participation among patients who underwent laparoscopic (LGBS) or open gastric bypass surgery (OGBS). Postoperative physical activity participation is considered important for achieving optimal weight loss and maintenance after gastric bypass surgery. However, no study has examined the relationship between surgery type and postoperative physical activity. Minimal invasiveness and reduced recovery time associated with LGBS compared with OGBS may permit earlier initiation and faster progression of postsurgical physical activity and potentially contribute to greater long-term adherence rates. Self-reported physical activity participation and aerobic physical activity hours per week at 2-weeks, 3-months, and 6-months postsurgery were assessed among LGBS and OGBS patients (presurgical body mass index of 35 to 70 kg/m2) at a university hospital from 1988-2002. Of the 2,235 patients, 531 (24%) and 1704 (76%) underwent LGBS and OGBS, respectively. A greater proportion of LGBS patients reported physical activity participation at each time point compared with OGBS patients (2 week, 76% vs 62%; 3 months, 84% vs 74%; 6 months, 85% vs 76%). Furthermore, LGBS patients reported a significantly greater physical activity duration at 2-weeks postsurgery compared with OGBS patients. A nonsignificant trend toward greater physical activity duration was observed in the LGBS patients at 3 months, whereas 6-month physical activity duration was similar between groups. LGBS, compared with OGBS, may promote earlier onset, progression, and maintenance of physical activity until 6 months postsurgery. Future studies need to prospectively determine whether LGBS, via facilitation of greater engagement in postsurgical physical activity, contributes to more successful weight loss and weight maintenance compared with OGBS.

Nourishing Our Understanding of Role Modeling to Improve Support and Health (NOURISH): Design and methods

Pediatric overweight is associated with numerous physical and psychological health risks, and overweight children are at significant risk for obesity in adulthood. African-American children are at particularly high risk for obesity and related health complications. However, this racial group has traditionally had limited access to obesity treatment and relatively few studies have included sufficient numbers of lower-SES, African American participants. Further, although parental involvement in treatment for pediatric overweight has been found to be beneficial, few studies have examined the efficacy of offering treatment exclusively to parents, a potentially cost-effective approach which could benefit the entire family. This pilot project will evaluate the efficacy of an intensive parenting intervention, (NOURISH; Nourishing Our Understanding of Role modeling to Improve Support and Health), targeting racially diverse parents of overweight children (ages 6-11). NOURISH addresses several urgent research priorities by targeting the underserved and addressing the significant disparity in obesity treatment services. Parents meeting study criteria (having a child between the ages of 6 and 11 with a BMI ≥ the 85th percentile) will be offered participation in the randomized trial comparing NOURISH with a control group. We hypothesize that children whose parents participate in NOURISH will manifest greater decreases in BMI, and greater improvements in dietary intake, and quality of life compared to children whose parents do not participate. This study is designed explicitly to gather preliminary feasibility, acceptability, and effectiveness data to inform a subsequent larger randomized controlled trial.

Parent skills training to enhance weight loss in overweight children: Evaluation of NOURISH

OBJECTIVE Although there is general agreement that parents should be involved in pediatric obesity treatment, few studies have investigated the effectiveness of interventions that target parents exclusively. Moreover, the effectiveness of this approach has not been adequately assessed with racially diverse families, particularly African Americans(AA), a group at high risk for elevated Body Mass Index (BMI). METHODS NOURISH (Nourishing Our Understanding of Role modeling to Improve Support and Health) is a culturally-sensitive parenting intervention targeting overweight (AA) children (ages 6-11; MBMI = 98.0%ile). Families (N = 84; 61% AA, 37% White) were randomly assigned to NOURISH or a control group. RESULTS NOURISH families significantly improved on child BMI from pre- to post-testing after adjustment for random effects, baseline BMI, and child race. NOURISH parents were very satisfied with the intervention and would recommend it to other parents; 91% strongly or moderately agreed that NOURISH helped them eat in a healthier manner. CONCLUSIONS These pilot data suggest that NOURISH is acceptable and, with refinement, offers promise for reducing pediatric BMI. Outcomes, lessons learned, and parent feedback will inform a larger randomized controlled trial.

LPS-stimulated tumor necrosis factor-alpha and interleukin-6 mRNA and cytokine responses following acute psychological stress

The purpose of this study was to examine the effect of acute psychological stress on LPS-stimulated TNF-α and IL-6 mRNA expression. Twenty-one healthy male subjects participated in 20 min of acute stress. Blood samples for norepinephrine and LPS-stimulated TNF-α and IL-6 cytokines and mRNA were drawn prior to, immediately after and 1-h after stress. Stress-induced increases in anxiety scores, cortisol, plasma norepinephrine, and heart rate demonstrated that the experimental protocol elicited an acute stress response. LPS-stimulated TNF-α mRNA decreased significantly immediately post-stress and partially recovered at 1h post-stress, whereas LPS-stimulated IL-6 mRNA exhibited a significant change across time, with an increase immediately after stress and a decrease 1h after stress. Trends in LPS-stimulated TNF-α and IL-6 cytokine concentrations followed the patterns of mRNA expression. A negative correlation of body mass index (BMI) and percent change of LPS-stimulated TNF-α mRNA was observed immediately post-stress, and BMI positively correlated with percent change of LPS-stimulated IL-6 cytokine levels immediately following stress. These findings demonstrated that acute psychological stress affects LPS-stimulated IL-6 and TNF-α gene expression. These results also indicate that BMI may impact the effects of psychological stress on cytokine responses to immune challenge. Further examination of the effects of stress on synthesis of other cellular cytokines and investigation of the association of BMI and stress responses will provide a more clear representation of the cytokine responses to acute psychological stress. In addition, studies examining the influence of gender on the response of immune cell subsets to acute stress and the possible mediating effect of BMI are warranted.