Exaggerated blood pressure (BP) response during exercise test reflects future risk of hypertension and has been shown to be related to increased left ventricular mass (LVM) in hypertensive patients. However, it is not known whether there is such a relationship in normotensives. The objective of this study is to investigate whether exercise BP response is related to left ventricular mass in normotensive subjects.Design and Method:
Among the normotensive (systolic blood pressure (SBP) < 120 mmHg and diastolic blood pressure (DBP) < 80 mmHg and no history of antihypertensive treatments or clinical cardiovascular diseases) subjects who underwent routine health screening, both exercise test and echocardiography results were available in 7607 men and women. Exercise test was done by Bruce protocol and SBP at stage 1 was used as an indicator of exercise BP response. Left ventricular mass was calculated by American Society of Echocardiography equation, and divided by body surface area to estimate LVM index.Results:
Mean age was 50 ± 7 years and proportion of male was 74%. Mean LVM index was 81.3 ± 16.0 gm/m2. Exercise SBP at stage 1 was significantly correlated to LVM index (r = 0.11, p < 0.0001) Higher exercise SBP at stage 1 was associated with increased LVM index after adjustment for age, gender, resting SBP and DBP, waist circumference and fasting glucose (p < 0.0001).Conclusions:
Higher SBP during low-intensity exercise was associated with increased LVM index in normotensive subjects. Exaggerated exercise BP response with normal clinic BP may indicate masked hypertension and possibly hidden target organ damage.