Abstract 14720: Determinants of Ethnic Differences in Cardiorespiratory Fitness: The Dallas Heart Study
Introduction: Studies have shown significant differences in cardiorespiratory fitness (CRF) among different ethnic groups. However, it is unclear how much of these differences can be explained by differences in body mass index (BMI), lifestyle behaviors and socioeconomic status (SES) among these groups.
Methods: The study consisted of Dallas Heart Study Phase 2 participants without cardiovascular disease who had a baseline CRF measurement using a submaximal treadmill test. CRF was estimated as the peak oxygen uptake (ml/kg/min) from a submaximal exercise heart rate measurement using the previously published Givoni’s equation and Hellerstein’s formula protocol. Lifestyle behaviors included in the analysis were self reported physical activity (PA) and smoking. Self reported education years and income were used as proxy measures of SES. Multiple multivariable adjusted linear regression models were constructed to determine the cross-sectional association of between ethnicity and cardiorespiratory fitness.
Results: A total of 2,665 participants [58% women, African American (AA) = 49%; Hispanics: 15%] were included in the analysis. AA participants had lower CRF compared to caucasians and hispanics (AA= 26.5 ± 10.3; Caucasians: 28.8 ± 9.7; Hispanics: 29.0 ± 9.8 ml/kg/min). This was consistent across all age groups among both males and females. On multivariable adjusted regression analysis, age, female sex, sedentary behavior, smoking and lower SES had significant inverse association with CRF. Both AA and Hispanic ethnicity had lower CRF after adjustment for age and sex (Table, Model 1). However, this association was considerably attenuated for AA and no longer significant for Hispanic ethnicity after additional adjustment for BMI, lifestyle behavior and SES (Table, Model 2, 3).
Conclusion: BMI, lifestyle and SES are important determinants of CRF in the general population and account for a significant proportion of ethnicity-based differences in CRF.
Author Disclosures: A. Pandey: None. C. Ayers: None. S. Das: None. S. Lakoski: None. J. De Lemos: None. J. Berry: None.
- © 2014 by American Heart Association, Inc.