Latino adolescents are disproportionately impacted by obesity and T2D, yet despite recent calls for action,10,22,23
very few culturally grounded diabetes prevention programs have been described in the literature for this population. This article describes a community-based participatory approach for developing and testing the feasibility of a 12-week lifestyle intervention and presents the preliminary efficacy of the intervention for improving T2D risk factors among obese Latino youth. The findings extend previous clinical studies in obese youth24,25
and support the translation of diabetes prevention programs for this population into community settings.
With the growing epidemic of obesity among children and adolescents, the Institute of Medicine has recently emphasized the importance of preventing obesity in young children.26
However, among children and adolescents who are already obese, targeting improvements in more proximal measures of diabetes risk such as reducing insulin resistance and/or improving glucose tolerance appear warranted.27
Insulin resistance, (ie, decreased insulin sensitivity), is thought to be one of the earliest pathophysiological processes of T2D.28
Insulin resistance prospectively predicts the development of T2D in adults,29
and adolescents with T2D are significantly more insulin resistant than obese controls.30
Therefore, increasing insulin sensitivity may be a key factor for preventing T2D in high-risk youth. Adolescents who participate in greater physical activity exhibit higher insulin sensitivity compared to more sedentary peers.31
Moreover, intervention studies support the utility of exercise to improve insulin sensitivity in obese adolescents.32,33
The amount of physical activity included in the ELSC intervention (ie, 60 minutes of moderate to vigorous physical activity 3 days/week) is a sufficient dose to improve insulin sensitivity in obese youth32
and may contribute to the observed health benefits.
Despite the improvement in insulin sensitivity, non-significant changes in weight and only small changes in BMI and BMI percentile were observed. However, significant reductions in waist circumference following the intervention were noted. Studies in adults suggest that exercise can result in significant reductions in waist circumference and/or abdominal obesity even in the absence of weight loss.34,35
Given the independent effect of abdominal adiposity on insulin resistance in Latino children36
and T2D in Latino adults,37
refocusing attention on reducing abdominal obesity to support health improvements rather than weight loss in this population may be prudent. As part of the lifestyle education curriculum, participants and their families were provided results of baseline laboratory testing in the context of T2D risk education. During the first session, families were informed that the goal of the ELSC program was to empower participants to improve health and reduce diabetes risk through healthy behaviors rather than weight loss. This message was reinforced throughout the program where adolescents and parents were encouraged to appreciate various aspects of health in a comprehensive manner.
Rather than promoting caloric restriction, the nutrition education sessions focused on the importance of eating breakfast, increasing fruit and vegetable consumption, reducing calories from fat and added sugar, portion control, and healthy snacking. Families were encouraged to set nutrition goals, share favorite recipes or foods, and the promotoras
facilitated discussion about ways to exchange unhealthy ingredients and cooking methods for healthier options (eg, substituting with low fat cheese and skim milk, grilling chicken instead of frying it). In addition, as part of the roles and responsibilities session, adolescents were encouraged to shop for and prepare a healthy meal for their families as a way for them to develop a sense of responsibility for their own as well as their family’s health. This is an important skill to develop during adolescence as the transition to adulthood brings greater autonomy and responsibility for food preparation and subsequent eating behaviors.38
The study was guided by an expanded ecodevelopmental model, which recognizes the importance of critical life periods in terms of disease pathogenesis as well as prevention.21
The ELSC-DDP specifically targeted adolescence as a critical developmental period for implementing targeted diabetes prevention programs. The pubertal transition is associated with specific biological as well as behavioral changes that are directly linked to T2D. From a biological perspective, puberty is associated with a physiological insulin resistance that is thought to contribute to T2D among high-risk adolescents.39
From a behavioral perspective, adolescence is associated with a significant decline in physical activity, which is thought to be steepest between ages 13 and 1840
and may further contribute to T2D risk. In this expanded ecodevelopmental model, these factors fall within individual and organic level systems, but including multiple external systems in order to facilitate individual health is proposed to be a more efficacious strategy. The ELSC-DPP intervention included the contextual-ecological influences of family, community, and sociocultural factors to support individual-level changes in health behaviors and outcomes. Family support was encouraged through participation in the lifestyle education sessions that were delivered in the community, by the community using a culturally grounded approach. The preliminary efficacy of this intervention may be, in part, attributable to the coordinated inclusion of these multiple systems (cultural, community, family) under a unified health enhancement approach, and thus likely introduced synergistic effects in support of healthy behavior changes among the individual participants. Scholars from the National Institute of Minority Health and Health Disparities have encouraged researchers to employ translational, transformation, and transdiciplinary approaches in order to shift the paradigm in health disparities research.41
The ecodevelopmental model, which is operationalized through the ELSC-DPP intervention, is one such approach that holds promise in closing the health disparities gap among minority youth.
Translating diabetes prevention programs into the community has proven to be a successful model for reducing diabetes risk and improving health outcomes in adults.42
The Diabetes Prevention Program (DPP) established that intensive lifestyle intervention can prevent (or delay) the onset of T2D in high-risk adults.43
Although the DPP employed a rigorous scientific approach, it was extremely costly and not immediately translatable into real-world settings.44
Furthermore, while the trial included a large number of minority participants, the intervention itself was not culturally grounded to meet the specific needs of minority individuals or communities. Since the publication of the DPP results, several studies have successfully adapted the DPP curriculum for use in community settings, many of which target minority populations, and a few have been implemented using a community-based participatory approach.42
These studies support the hypothesis that culturally tailored diabetes prevention programs delivered in the community setting may provide the best opportunity for closing the diabetes-related health disparities gap. The ELSC-DPP extends previous adult models of implementing culturally grounded community-based diabetes prevention interventions to a group of high-risk Latino adolescents.
This program is somewhat unique to other community-based health programs for youth in that the delivery of the intervention was not in partnership with schools or the school system. Previous school-based obesity interventions have yielded modest effects on weight-related outcomes and very few have been successful in terms of reducing T2D risk factors in adolescents.45
Although schools may appear to be a logical venue for implementing diabetes prevention programs for children and adolescents, the limited success of previous studies and the economic challenges schools are facing suggest that alternative community-based strategies be tested. The ELSC-DPP was delivered in a YMCA located in a large municipal setting. The primary reason for partnering with the YMCA was the mutual interest in developing diabetes prevention programs for Latino youth in the collective community. However, from a public health perspective, the YMCA may be an ideal venue to deliver diabetes prevention programs on a large scale. It is estimated that ~70 million US households live within 3 miles of a YMCA and the YMCA reaches more than 10 million children and adolescents in over 10 000 US communities.46
From a policy perspective, the YMCA’s mission is to strengthen the communities it serves regardless of gender, income, faith, sexual orientation, or cultural background. Furthermore, the YMCA has proven to be a viable venue for translating the DPP curriculum into the community to prevent diabetes in high-risk adults.47
Taken together, these results suggest that culturally grounded diabetes prevention programs for Latino youth can be successfully delivered in the community setting through the YMCA.
The strength of this study includes the focus on a high-risk population of adolescents, a culturally grounded intervention developed in collaboration with the community for delivery in the community, and the inclusion of robust measures of T2D risk. Despite these strengths, there are limitations that are worthy of comment. First, the relatively small sample size may limit the power to detect smaller effect sizes, as well as limiting the generalizability of our findings. However, this was a feasibility study and the intervention was developed specifically to meet the needs of obese Latino adolescents in a defined community. While these findings may not be generalizable, this approach can and should be tested in other communities and populations, given a local adaptation to ground the intervention consistent with the culture of the local community. The lack of a randomized control design also limits the ability to draw definitive conclusions as to whether the results were uniquely attributable to the intervention relative to an alternate source of influence. Clearly it is important to maintain scientific rigor in order to conduct sound science, but in order for translational science to truly be transformative, approaches must be viable in real-world settings.48
It is challenging enough for scientists to establish the necessary rapport and trust to develop meaningful collaborations with vulnerable communities, and to expect these communities to agree to exclude up to half of their population from receiving potential health benefits (ie, randomized to a control or usual care group) may be unrealistic and do little to close the widening health disparities gap.48
Nevertheless, future studies should evaluate the efficacy of similar programs against a more traditional control or reference group.
In conclusion, these promising results suggest that a culturally grounded community-based lifestyle intervention program can reduce T2D risk factors among obese Latino adolescents. Translational approaches that include community collaboration and family involvement to improve robust individual health outcomes among high-risk youth should be tested in various populations. If successful, this approach may substantially reduce the overall burden of obesity-related disease in our society.