A lifestyle intervention improves plasma insulin levels among Native American high school youth

Background. Worldwide, type 2 diabetes prevalence is increasing, with Native American populations particularly at risk. The Zuni Pueblo, with a history of wellness activities, volunteered to test the feasibility and efficacy of a high school-based diabetes prevention intervention. Methods. This school-based intervention used a multiple cross-sectional design to evaluate outcome measures at 0, 1.5, and 3 years against an Anglo comparison group. The Zuni high school diabetes prevention program included an educational component targeting decreased consumption of sugared beverages, knowledge of diabetes risk factors, and a youth-oriented fitness center. Main outcome measures were plasma glucose and insulin measured fasting and 30 min after a 75-g glucose challenge. Results. Plasma glucose levels were normal at baseline for Zuni (n = 72) and Anglo (n = 37) youth and did not significantly change throughout the study. At baseline, fasting and 30-min plasma insulin levels were significantly elevated for Zuni youth; they showed significant steady declines for both males and females throughout the study (P = 0.06 to P = 0.000 for trends using quantile regression). By Year 3, values for Zuni males (n = 29) equaled Anglo comparison values, while Zuni female (n = 26) values had declined but were still higher than Anglo comparison values. Conclusions. Among at-risk youth, an environmentally based lifestyle intervention may significantly suppress markers of type 2 diabetes risk.