Kelly R. Theim

Orthopedic Complications of Overweight in Children and Adolescents

OBJECTIVE. Few studies have quantified the prevalence of weight-related orthopedic conditions in otherwise healthy overweight children. The goal of the present investigation was to describe the musculoskeletal consequences of pediatric overweight in a large pediatric cohort of children that included severely overweight children. METHODS. Medical charts from 227 overweight and 128 nonoverweight children and adolescents who were enrolled in pediatric clinical studies at the National Institutes of Health from 1996 to 2004 were reviewed to record pertinent orthopedic medical history and musculoskeletal complaints. Questionnaire data from 183 enrollees (146 overweight) documented difficulties with mobility. In 250, lower extremity alignment was determined by bilateral metaphyseal-diaphyseal and anatomic tibiofemoral angle measurements made from whole-body dual-energy x-ray absorptiometry scans. RESULTS. Compared with nonoverweight children, overweight children reported a greater prevalence of fractures and musculoskeletal discomfort. The most common self-reported joint complaint among those who were questioned directly was knee pain (21.4% overweight vs 16.7% nonoverweight). Overweight children reported greater impairment in mobility than did nonoverweight children (mobility score: 17.0 ± 6.8 vs 11.6 ± 2.8). Both metaphyseal-diaphyseal and anatomic tibiofemoral angle measurements showed greater malalignment in overweight compared with nonoverweight children. CONCLUSIONS. Reported fractures, musculoskeletal discomfort, impaired mobility, and lower extremity malalignment are more prevalent in overweight than nonoverweight children and adolescents. Because they affect the likelihood that children will engage in physical activity, orthopedic difficulties may be part of the cycle that perpetuates the accumulation of excess weight in children.

A Prospective Study of Psychological Predictors of Body Fat Gain Among Children at High Risk for Adult Obesity

OBJECTIVE. Limited data suggest that psychological factors, including binge eating, dieting, and depressive symptoms, may predispose children to excessive weight gain. We investigated the relationship between baseline psychological measures and changes in body fat (measured with dual-energy x-ray absorptiometry) over time among children thought to be at high risk for adult obesity. METHODS. A cohort study of a convenience sample of children (age: 6–12 years) recruited from Washington, DC, and its suburbs was performed. Subjects were selected to be at increased risk for adult obesity, either because they were overweight when first examined or because their parents were overweight. Children completed questionnaires at baseline that assessed dieting, binge eating, disordered eating attitudes, and depressive symptoms; they underwent measurements of body fat mass at baseline and annually for an average of 4.2 years (SD: 1.8 years). RESULTS. Five hundred sixty-eight measurements were obtained between July 1996 and December 2004, for 146 children. Both binge eating and dieting predicted increases in body fat. Neither depressive symptoms nor disturbed eating attitudes served as significant predictors. Children who reported binge eating gained, on average, 15% more fat mass, compared with children who did not report binge eating. CONCLUSIONS. Children’s reports of binge eating and dieting were salient predictors of gains in fat mass during middle childhood among children at high risk for adult obesity. Interventions targeting disordered eating behaviors may be useful in preventing excessive fat gain in this high-risk group.

Behavioral Economic Predictors of Overweight Children's Weight Loss

OBJECTIVE Our goal was to determine whether behavioral economic constructs-including impulsivity (i.e., steep discounting of delayed food and monetary rewards), the relative reinforcing value of food (RRVfood), and environmental enrichment (i.e., the presence of alternatives to unhealthy foods in the home and neighborhood environments)-are significant pretreatment predictors of overweight childrens weight loss within family-based treatment. METHOD Overweight children (N = 241; ages 7-12 years; 63% female; 65% non-Hispanic White) enrolled in a 16-week family-based obesity treatment with at least one parent. At baseline, children completed a task to assess RRVfood and delay discounting measures of snack foods and money to assess impulsivity. Parents completed questionnaires to assess environmental enrichment. RESULTS Children who found food highly reinforcing and steeply discounted future food rewards at baseline showed a blunted response to treatment compared with children without this combination of risk factors. High environmental enrichment was associated with treatment success only among children who did not find food highly reinforcing. Monetary discounting rate predicted weight loss, regardless of childrens level of RRVfood. CONCLUSIONS Investigation is warranted into novel approaches to obesity treatment that target underlying impulsivity and RRVfood. Enriching the environment with alternatives to unhealthy eating may facilitate weight loss, especially for children with low RRVfood.

What constitutes clinically significant binge eating? Association between binge features and clinical validators in college‐age women

OBJECTIVE To investigate the association between binge features and clinical validators. METHOD The Eating Disorder Examination assessed binge features in a sample of 549 college-age women: loss of control (LOC) presence, binge frequency, binge size, indicators of impaired control, and LOC severity. Clinical validators were self-reported clinical impairment and current psychiatric comorbidity, as determined via a semistructured interview. RESULTS Compared with women without LOC, those with LOC had significantly greater odds of reporting clinical impairment and comorbidity (ps < 0.001). Among women with LOC (n = 252), the indicators of impaired control and LOC severity, but not binge size or frequency, were associated with greater odds of reporting clinical impairment and/or comorbidity (ps < 0.05). DICUSSION: Findings confirm that the presence of LOC may be the hallmark feature of binge eating. Further, dimensional ratings about the LOC experience--and possibly the indicators of impaired control--may improve reliable identification of clinically significant binge eating.

The Use of Biosimulation in the Design of a Novel Multilevel Weight Loss Maintenance Program for Overweight Children

Weight loss outcomes achieved through conventional behavior change interventions are prone to deterioration over time. Basic learning laboratory studies in the area of behavioral extinction and renewal and multilevel models of weight control offer clues as to why newly acquired weight loss skills are prone to relapse. According to these models, current clinic‐based interventions may not be of sufficient duration or scope to allow for the practice of new skills across the multiple community contexts necessary to promote sustainable weight loss. Although longer, more intensive interventions with greater reach may hold the key to improving weight loss outcomes, it is difficult to test these assumptions in a time efficient and cost‐effective manner. A research design tool that has been increasingly utilized in other fields (e.g., pharmaceuticals) is the use of biosimulation analyses. The present study describes our research teams use of computer simulation models to assist in designing a study to test a novel, comprehensive socio‐environmental treatment approach to weight loss maintenance in children ages 7–12 years. Weight outcome data from the weight loss, weight maintenance, and follow‐up phases of a recently completed randomized controlled trial (RCT) were used to describe the time course of a proposed, extended multilevel treatment program. Simulations were then conducted to project the expected changes in child percent overweight (POW) trajectories in the proposed study. A 12.9% decrease in POW at 30 months was estimated based upon the midway point between models of “best‐case” and “worst‐case” weight maintenance scenarios. Preliminary data and further analyses, including biosimulation projections, suggest that our socio‐environmental approach to weight loss maintenance treatment is promising and warrants evaluation in a large‐scale RCT. Biosimulation techniques may have utility in the design of future community‐level interventions for the treatment and prevention of childhood overweight.

Obesity and the US military family.

This review discusses the current knowledge and future directions regarding obesity within the US military family (i.e., active‐duty servicemembers, as well as military spouses, children, retirees, and veterans). The increasing rates of overweight and obesity within the US military adversely impact military readiness, limit recruitment, and place a significant financial burden on the Department of Defense.

Importance of Early Weight Change in a Pediatric Weight Management Trial

OBJECTIVE: Early weight change is associated with overall weight loss treatment response in adults but has been relatively unexplored in youth. We investigated the importance of early weight change in a pediatric weight control trial. METHODS: Overweight children aged 7 to 12 years (n = 204) participated in a randomized controlled trial of 2 weight maintenance treatments (MTs) after a 20-week family-based behavioral weight loss treatment (FBT). Hierarchical regression was used to investigate the relation between childrens percentage weight change at sessions 4, 6, and 8 of FBT and BMI z-score reductions after FBT and at the 2-year follow-up. Correlations and hierarchical regression were used to identify child and parent factors associated with childrens early weight change. RESULTS: Childrens percentage weight change by FBT session 8 was the best predictor of BMI z-score reductions after FBT and at 2-year follow-up. Percentage weight change in children at session 8 was associated with better FBT attendance and with greater percentage weight change in parents at FBT session 8. CONCLUSIONS: Early weight change seems to be related to treatment response through the end of treatment and 2-year follow-up. Future research should include investigation of strategies to promote early weight change in children and parents and identification of mechanisms through which early weight change is related to overall treatment response.

Adherence to Behavioral Targets and Treatment Attendance during a Pediatric Weight Control Trial

Better weight loss outcomes are achieved in adults and youth who adhere to obesity treatment regimens (i.e., session attendance and prescribed changes in weight control behaviors). However, more research is needed regarding childrens adherence to a range of behaviors relevant for weight maintenance over long‐term follow‐up.

Estimates of body fat in children by Hologic QDR-2000 and QDR-4500A dual-energy X-ray absorptiometers compared with deuterium dilution.

ABSTRACT We evaluated the accuracy with which the Hologic QDR-4500A and QDR-2000 densitometers measure fat mass (FM) in 95 children. FM was derived from total body water measured by deuterium dilution (DD) in all children, by QDR-4500A in 50, and by QDR-2000 in 45 children. Compared with DD, both instruments underestimated FM (QDR-4500A: 3.35 ± 2.5 kg, P < 0.0001; QDR-2000: 1.05 ± 1.5 kg, P < 0.0001). Both absorptiometers showed magnitude biases relative to DD (QDR-4500: r = +0.70, P < 0.001; QDR-2000: r = −0.51, P < 0.001). We conclude that neither densitometer is equivalent to DD for estimation of childrens FM. The QDR-4500As current calibration seems to provide an even greater underestimate of FM than the QDR-2000.

Preventing Obesity in the Military Community (POMC): The Development of a Clinical Trials Research Network

Obesity impacts the U.S. military by affecting the health and readiness of active duty service members and their families. Preventing Obesity in Military Communities (POMC) is a comprehensive research program within Patient Centered Medical Homes (PCMHs) in three Military Training Facilities. This paper describes three pilot randomized controlled trials that target critical high risk periods for unhealthy weight gain from birth to young adulthood: (1) pregnancy and early infancy (POMC-Mother-Baby), (2) adolescence (POMC-Adolescent), and (3) the first tour of duty after boot camp (POMC-Early Career). Each study employs a two-group randomized treatment or prevention program with follow up. POMC offers a unique opportunity to bring together research and clinical expertise in obesity prevention to develop state-of-the-art programs within PCMHs in Military Training Facilities. This research builds on existing infrastructure that is expected to have immediate clinical benefits to DoD and far-reaching potential for ongoing collaborative work. POMC may offer an economical approach for widespread obesity prevention, from conception to young adulthood, in the U.S. military as well as in civilian communities.