Background: It has been previously reported that an exaggerated response of blood pressure to mental stress tasks is associated to an increased cardiovascular risk. The objective of this cross-sectional study, with sequential inclusion of subjects who met the inclusion criteria, was to asses the relationships between the response of blood pressure and heart rate to two different mental stress tasks and early target organ-damage, defined as abnormalities in the echocardiogram and/or an increase of urinary albumin excretion (UAE) or microalbuminuria, in untreated mild hypertensive subjects.
Subjects and methods: Two hundred and eleven subjects aged 18 to 65 years (56% males) with mild hypertension (SBP between 140-180 mmHg and/or DBP between 90-105 mmHg) were included in Hospitalet Study. One hundred and thirty seven of them accepted to participate in the study of cardiovascular reactivity. Two different tasks were applied in the same day: a stressful interview (SI) and a mental arithmetic stress tasks (MAST). An echocardiogram of good quality was obtained in 123 cases (89.8%) and 24 h UAE was measured in 108 cases (78.8%).
Results: The prevalence of left ventricular hypertrophy was 21.1% (95% CI = 14.3-29.4) and the prevalence of microalbuminuria was 15.7% (95% CI = 9.4-24.4%). After adjusting for the baseline blood pressure, a significant correlation was observed between increase of systolic BP during SI and UAE (r = 0.21; p = 0.03) and between increase of diastolic BP during SI and relative wall thickness (r = 0.32; p < 0.005). When we analyzed the changes of BP during MAST, a significant correlation was observed between increase of diastolic BP (adjusted for baseline diastolic BP) and left atrial size (r = 0.21; p = 0.02). We did not find any significant correlation between the increases of BP (systolic or diastolic) during MAST or increases of heart rate during both tasks and left ventricular mass index or UAE.
Conclusions: A weak correlation was observed between cardiovascular reactivity of blood pressure during mental stress tasks and early target organ damage in mild hypertension. We did not find any relationship between the response to heart rate during the tasks and early target organ damage.