Hypertension and Ventilatory Ineffciency During Exercise in the Fitness Registry and the Importance of Exercise National Database (FRIEND)

Background: Ventilatory ineffciency (high minute ventilation/rate of carbon dioxide production [V̇E/V̇CO2] slope) during exercise is more common in patients with metabolic syndrome and cardiovascular disease, and is prognostic of cardiovascular mortality. Interestingly, new data suggest that adults with controlled or untreated, but not uncontrolled, primary hypertension (HTN) have ventilatory ineffciency during exercise. However, the sample sizes were modest (n=~20/group). Therefore, we used a large database to test the hypothesis that adults with controlled or untreated, but not uncontrolled, primary HTN have higher V̇E/V̇CO2 slope than adults with no HTN. Methods: We used American Heart Association guidelines for HTN as systolic blood pressure [BP] ≥130mmHg, diastolic BP ≥80, or anti-HTN medication in the Fitness Registry and the Importance of Exercise National Database (FRIEND). To isolate primary HTN, we excluded those with any disease other than HTN, any medication use other than anti-HTN medication(s), current smoking status, and/or obesity (body mass index [BMI]≥30). The V̇E/V̇CO2 slope was determined from a peak cycling exercise test. We excluded adults with a peak respiratory exchange ratio <1.00 during exercise. All data are presented as median[IQR]. We compared groups using linear regression unadjusted and adjusted for sex, fitness, and age. Results: The sample (n=4,659) characteristics were age: 42[18] years old (range 18-91 years); 52% with HTN; 18% female; BMI: 26.0[4.0] kg/m2; cardiorespiratory fitness: 28.5[11.0] mL O2/kg/min; race/ethnicity: <1% American Indian, 3% Asian, 12% Black, 8% Hispanic, 4% Other, & 73% White. The V̇E/V̇CO2 slope during exercise was higher in adults without HTN (n=2,410; 24.9[3.8]) compared to those with uncontrolled HTN (n=252; 24.7[3.0]; standard error of the estimate[SE]: -0.20, 95% confidence interval[CI]: -0.33 to -0.07, p=0.003), but not controlled HTN (n=132; 24.4[3.4]; SE: -0.14, 95%CI: -0.31 to 0.04, p=0.12) or untreated HTN (n=1,865; 24.7[3.7]; SE: -0.05, 95%CI: -0.11 to 0.009, p=0.09) (model: R2=0.002, F3,4655=3.83, p=0.009). However, no pairwise differences were observed after covariate adjustment (model: R2=0.117, F6,4652=103, p<0.001). Conclusion: In contrast to our hypothesis, these data from the FRIEND indicate that primary HTN is not associated with ventilatory ineffciency (i.e., higher V̇E/V̇CO2 slope). National Institutes of Health K01HL160772 (JCW), American Heart Association 23CDA1037938 (JCW). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.