573 - Association Between Cardiorespiratory Fitness and Diurnal Blood Pressure in Adolescents With Excessive Weight

Publication Number: 4561.573

Eva C. Diaz, University of Arkansas for Medical Sciences and Arkansas Children's Nutrition Center, Little Rock, AR, United States; Jeny Rivera, University of Arkansas for Medical Sciences College of Medicine, United States, AR, United States; Andrew W. Brown, Arkansas Children’s Research Institute, Little Rock, AR, United States; Simon Chung, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Sean H.. Adams, Dept. of Surgery, UC Davis, Sacramento, CA, United States; Christina Potts, Arkansas Children's Hospital, Little Rock, AR, United States; Richard Blaszak, University of Arkansas for Medical Sciences College of Medicine, Little Rock, AR, United States; Elisabet Børsheim, UAMS, Arkansas Children's Nutrition Center, Little Rock, AR, United States; Ilyas Mohammad, UAMS, Little rock, AR, United States

Background: Cardiorespiratory fitness (V̇O2peak) is increasingly recognized as an important predictor of cardiometabolic health of children. However, the relationship between V̇O2peak and diurnal variations in blood pressure of adolescents remains unclear.

Objective: The purpose of this preliminary analysis was to evaluate the association of V̇O2peak and diurnal blood pressure in adolescents with excessive weight (BMI percentile ≥ 85th), using 24-hour ambulatory blood pressure monitoring (ABPM). We hypothesized that V̇O2peak is inversely associated with 24-hour average, wake, and sleep systolic and diastolic blood pressure (SBP and DBP, mmHg), and positively associated with SBP / DBP nocturnal blood pressure dipping.

Design/Methods: Analyses were conducted using baseline measurements obtained from adolescents participating in a clinical trial at the Arkansas Children’s Nutrition Center. V̇O2peak (ml·min-1·kg-1) was assessed by measuring gas exchange during an incremental cycle ergometer test. Twenty-four-hour ABPM was performed at least one week after the fitness test and before randomization to the intervention. Nocturnal dipping was defined as the percent decline in mean SBP / DBP during sleep compared with daytime. The association between V̇O2peak and blood pressure was examined using generalized linear regression analysis, controlling for age, race, and sex.

Results: Children (n = 27) were 15.8 ± 1.4 years old, with a BMI percentile of 94.8 ± 5.7. Fifty-nine percent were boys, 56% were White non-Hispanic, and 26% were Black non-Hispanic. SBP and DBP dipping were directly associated with V̇O2peak (SBP dipping: β = 0.52, 95% CI = 0.14 to 0.91, p = 0.008; DBP dipping = 0.52, 95% CI = 0.08 to 0.95, p = 0.019). For every unit increased in V̇O2peak SBP and DBP dipping increased by 0.52 percentage points. Compared to White children, children of Black race experienced less % blood pressure dipping (SBP dipping: β = -3.55, 95% CI = -11.14 to -1.30, p = 0.013; DBP dipping: β = -6.50 95% CI = -12.02 to -0.96, p = 0.021).

Conclusion(s): Higher cardiorespiratory fitness was associated with greater systolic and diastolic blood pressure dipping among adolescents with excessive weight, suggesting a beneficial role of aerobic fitness in maintaining normal circadian blood pressure patterns.

Funding: NIH-NIGMS 5P20GM109096. USDA-ARS 6026-10700-001-000D