Family-Based Obesity Treatment, Then and Now: Twenty-Five Years of Pediatric Obesity Treatment

Family-based behavioral pediatric obesity treatment programs were developed over 25 years ago, and both short- and long-term results support their efficacy (Epstein, Myers, Raynor, & Saelens, 1998; Epstein, Valoski, Wing, & McCurley, 1990, 1994; Jelalian & Saelens, 1999). Obesity runs in families (Whitaker, Wright, Pepe, Seidel, & Dietz, 1997), and it has been hypothesized that targeting eating and activity change in the child and parent, along with teaching parents behavioral skills to facilitate child behavior change, could mobilize family resources to improve the efficacy of childhood obesity treatments. Simultaneously treating the parent and child benefits both, and creates positive relationships between child and parent weight change (Wrotniak, Epstein, Paluch, & Roemmich, 2004, 2005). The efficacy of family-based treatments has been replicated many times since the late 1970s (Epstein, 2003), but there has been no attempt to evaluate changes in efficacy over time. Several variables have changed over that period that may influence the effectiveness of family-based treatments. These include changes in the characteristics of youth who are being treated for pediatric obesity, changes in the environment and family structure that may require conceptual changes in components of family-based treatment, and changes in the analysis and reporting of clinical trials. There has been an increase in the incidence and prevalence of pediatric obesity over the last 20 years (Ogden, Flegal, Carroll, & Johnson, 2002; Troiano, Flegal, Kuczmarski, Campbell, & Johnson, 1995). The body mass index (BMI) distribution is positively skewed; the average overweight child today is more overweight than the average overweight child in the 1970s and 1980s. More overweight youth may show greater decreases in percentage overweight. It is also possible that the more overweight the child is, the more the environment has influenced the child and the poorer the child’s eating and exercise habits may be. Thus, treatment effectiveness may suffer. There is general agreement that the increase in obesity is due in part to changes in the environment (Hill, Wyatt, Reed, & Peters, 2003) that can lead to decreased energy expenditure and increased food intake (French, Story, & Jeffery, 2001). Almost all homes have at least one television, and there has been an increase in the percentage of homes with multiple televisions (Neilsen Media Research 2000, 2000) and in the percentage of children with televisions in their bedrooms (Dennison, Erb, & Jenkins, 2002). Television watching has been associated with obesity in youth (Crespo et al., 2001; Gortmaker et al., 1996). Eating is often paired with television watching in youth (Matheson, Killen, Wang, Varady, & Robinson, 2004; Saelens et al., 2002), and television watching is related to energy intake (Epstein, Roemmich, Paluch, & Raynor, 2005b; Taras et al., 1989). Television watching may shift time away from physical activity (Durant, Baranowski, Johnson, & Thompson, 1994; Epstein, Roemmich, Paluch, & Raynor, 2005a; Taras, Sallis, Patterson, Nader, & Nelson, 1989), reducing energy expenditure. Youth make the choice to be active or sedentary, and developments in behavioral choice theory provide a theoretical framework for interventions to reduce sedentary behaviors (Epstein & Roemmich, 2001; Epstein & Saelens, 2000). Two recent studies in our research program have focused on behavioral economic approaches to modify sedentary behavior as part of a comprehensive treatment for pediatric obesity (Epstein, Paluch, Gordy, & Dorn, 2000; Epstein, Paluch, Kilanowski, & Raynor, 2004). Changes in the environment also influence energy intake (French et al., 2001). There has been an increase in added fats and oils to the food supply (Kantor, 1999). Cheese and pizza consumption (Putnam & Gerrior, 1999) and soda consumption (Tippett & Cleveland, 1999) have increased while milk intake has decreased (Tippett & Cleveland, 1999). In combination with the increase in the number of working mothers and single-parent families (Bowers, 2000), there has been an increase in meals in restaurants (National Restaurant Association, 1998) and energy consumed from eating out (Biing-Hwan, Guthrie, & Frazao, 1999). As people eat out, they experience greater portion sizes (Rolls, 2003), which increases consumption. Behavioral economics also provides ideas for new approaches to reducing energy intake in obese youth. On the basis of research showing that obese youth and adults (Legerski & Epstein, 2006; Saelens & Epstein, 1996) are more motivated to eat than are their leaner peers, in one of our recent studies we attempted to identify nonfood alternatives to compete with the reinforcing value of food (Epstein, Roemmich, Stein, Paluch, & Kilanowski, 2005). There have been changes in the family since the 1950s. The divorce rate more than doubled from 1950 to 1970 (15/1,000 to 40/1,000 per year) and remained stable from 1970 to 1988 (Shiono & Quinn, 1994). The number of families in which both parents work has increased (Anderson & Butcher, 2006), which has resulted in greater income but made it more challenging for parents to allocate enough time for children in family-based behavioral treatment interventions that focus on teaching behavioral principles and modification of the environment. Changes in family life may increase parents’ distress, which also may affect treatment effectiveness (Zeller, Saelens, Roehrig, Kirk, & Daniels, 2004). We tested an intervention that taught problem-solving skills that may be useful in coping with changes in family life that have evolved over time (Epstein, Paluch, Gordy, Saelens, & Ernst, 2000). There are methodological reasons for reexamining studies completed in the 1970s and early 1980s. Older studies used height and weight charts for children (Jelliffe, 1966). When children became older than 18, their overweight status was evaluated with the use of adult height and weight charts (Metropolitan Life Insurance Company, 1959, 1983), which were derived using different methods from a different sample than the youth charts. BMI charts were introduced in 1991 (Must, Dallal, & Dietz, 1991) and have been updated (Kuczmarski et al., 2002). BMI charts use the same methods for parents and children, and the BMI curves represent smooth functions between child and young adult age ranges. It is possible that results obtained using older standards, or even different versions of BMI charts, would show different efficacy when current standards are applied. There have been changes in the reporting of randomized clinical trials in obesity during the last 25 years. Studies completed over 2 decades ago generally reported data for study completers, along with the rate of attrition. It is now common to consider intention to treat, whereby everyone who is randomized and begins the study is accounted for. There have also been changes in the analytical approaches to longitudinal data. Mixed-effects regression models can be used to analyze differences in the patterns of between-groups change over time, as well as predictors of the pattern of change over time (Bryk & Raudenbush, 1987; Goldstein, 1995). Mixed-effects regression models use all the data that are available, as these models do not delete participants with missing data and can analyze data obtained at different time points across studies. Mixed-effects regression models take into account serial correlation between repeated observations and changes in the variability over time, which is relevant because increases in variability for weight control over time are commonly observed in obesity treatment studies. The aims of this study included assessment of changes over time for treatments implemented 25 years ago or current family-based treatments across eight studies (Epstein, Paluch, Gordy, & Dorn, 2000; Epstein, Paluch, Gordy, Saelens, & Ernst, 2000; Epstein, Paluch, Kilanowski, & Raynor, 2004; Epstein, Wing, Koeske, Andrasik, & Ossip, 1981; Epstein, Wing, Koeske, & Valoski, 1984, 1985, 1986; Epstein, Wing, Valoski, & Gooding, 1987) using the same dependent measures (Kuczmarski et al., 2002) and the identification of participant characteristics related to treatment success. The family-based behavioral treatment program for overweight youth is well standardized, with a common core used across all the studies, facilitating the comparison of treatment effects over time. The research program represents a systematic approach to the design of family-based treatments that has focused on different aspects of treatment, including the influence of the family and parent weight, comparison of lifestyle and programmed aerobic activity, the influence of problem solving on treatment outcome, and the influence of methods to reduce sedentary behaviors such as watching television and playing computer games (Epstein, 2003). In addition to evaluating the period during which the study was implemented, we reevaluated long-term (10-year) results for the earlier studies using z-BMI standards and contemporary analytic methods. To identify clinical significance, we also assessed differences in the dichotomous outcomes of achieving BMI values below the overweight (95th BMI percentile) and at risk for overweight (85th BMI percentile) values, as well as reductions greater than 0.5 or 1.0 standard deviation units. This article is unique in the ability to (a) compare a standardized treatment for effectiveness over a long period that overlapped periods of environmental changes that have been hypothesized to increase the prevalence of obesity and to (b) use a large data set to assess how participant characteristics may be related to treatment outcome.