Reliability of blood pressure responses used to define an exaggerated blood pressure response to exercise in young healthy adults

Abstract

Exaggerated blood pressure (BP) responses (EBPR) to exercise are prognostic of future cardiovascular risk. The primary objective of this study was to assess the test-retest reliability of BP responses used to categorize EBPR as absent or present. Twenty-seven healthy adults [21(2) years; 12 males] with resting BP < 130/80 mmHg completed a modified Bruce protocol treadmill exercise test on two visits separated by 6 (3) days. BP measurements were obtained during exercise using an automated auscultatory device. Submaximal and maximal systolic and diastolic BP, the change in diastolic BP from rest to maximal diastolic BP, and the change in systolic BP relative to the change in exercise intensity, quantified using the metabolic equivalent of task (SBP/MET-slope) were determined. Test-retest reliability of these BP responses was assessed using intraclass correlation coefficients (ICC) with a value ≥0.61 considered as substantial reliability. Submaximal diastolic BP demonstrated substantial reliability in the total group (ICC = 0.670; P ≤ 0.001). In males, submaximal systolic BP (ICC = 0.655, P < 0.01), submaximal diastolic BP (ICC = 0.699; P < 0.01) and maximal systolic BP (ICC = 0.794; P ≤ 0.001) demonstrated substantial reliability. All other BP responses were not reliable. Despite the prognostic value of EBPR, only three BP responses used to categorize EBPR demonstrated substantial test-retest reliability in healthy young males. In clinical practice, these preliminary findings would support the use of exercise BPs to identify young males with elevated cardiovascular risk, but additional research is needed to improve the clinical utility of exercise BPs and EBPR in females.