Abstract P358: Racial Differences in Determinants and Timing of Dropout From an Exercise Intervention: The STRRIDE Trials

Abstract

Introduction: Most adults recognize the positive health benefits of being physically active and maintaining a healthy weight, yet inactivity and obesity rates continue to rise. This disconnect is even more pronounced among racial and ethnic minorities across the United States, with Black/African American women being the highest risk group for inactivity an obesity. To begin to close this growing racial disparity gap, racial differences in exercise intervention dropout must be assessed. Hypothesis: We hypothesized that compared to their White counterpart, Black participants would dropout earlier and more often due to environmental factors. Methods: A total of 947 adults with dyslipidemia (STRRIDE I, STRRIDE AT/RT) or prediabetes (STRRIDE-PD) were randomized to either inactive control or to 1 of 10 exercise interventions, ranging from doses of 8 to 23 kcal/kg/wk, intensities of 50% to 75%VO 2 peak, and durations of 6 to 8 months. Two groups included resistance training, and one included dietary intervention (7% weight loss goal). Dropout was defined as an individual who withdrew from the study. Timing of intervention dropout was defined as the last session attended and categorized into phases. Chi-square or t -tests assessed differences in baseline characteristics by race. Results: Black versus White participants were on average younger (50.7 ± 7.7 vs. 56.0 ± 8.9 years; p<0.01), however they had similar fitness levels (24.5 ± 6.0 vs. 24.7 ± 5.5 ml/kg/min; p=0.83) and body mass indexes (31.6 ± 3.1 vs. 30.8 ± 3.1 kg/m 2 ; p=0.07). Black participants were particularly more likely to dropout during the ramp period (43.1% vs. 35.4%) of the exercise intervention compared to their White counterparts. Black participants were more likely to dropout because they lacked time (43.2% vs. 38.7%), work responsibilities (26.3 % vs. 14.3%), were lost to follow-up (23.9% vs. 14.6%), had transportation issues (4.6% vs 0.0%), changed their mind (10.2% vs. 8.5%), or lack of motivation (10.5% vs. 1.3%). Conclusions: Understanding racial differences among determinants and timing of exercise intervention dropout provides key insights for future interventions aiming to optimize exercise adoption and adherence. These insights will in turn improve cardiometabolic risk among this understudied minority group.