Hypertensive effect of bronchial asthma

الملخص EN

Background : Both bronchial asthma and hypertension are spastic disorders of smooth muscle, salt sensitive and sometimes associated with higher renin-angiotensin system activity, suggesting similarities between their aetiologies.

This study was intended to assess the blood pressure status in asthmatic patients.

Patients and Methods : The study involved two groups: a control group of 56 healthy subjects matched for gender and age with the study group of 100 patients with a medical history of asthma but no other respiratory disease.

Asthma history was recorded to assess asthma activity at the time of examination together with medications.

The non-invasive ausculatory method was used for measuring the systolic (SBP) and diastolic (DBP) blood pressures.

Mean arterial blood pressure (MABP) was determined by the formula: MABP = DBP + [(SBP – DBP) / 3].

Results : DBP was significantly higher in asthmatics (mean±SD = 80±10 mmHg) compared with non-asthmatics (mean ± SD = 75 ± 10 mmHg) (P = 0.002).

DBP of off-treatment asthmatics was significantly higher compared with that of non-asthmatics (P = 0.015).

Diastolic blood pressure of asymptomatic patients was not significantly higher compared with that of symptomatic patients (P = 0.774).

Systolic and mean arterial blood pressures were not significantly different in asthmatics and control groups (P = 0.267 and 0.116 respectively).

Conclusions : In contrast to systolic and mean arterial blood pressures, diastolic blood pressure was significantly elevated in asthmatics (even in off-treatment patients) compared with non-asthmatics indicating mechanisms that predominantly increases peripheral vascular resistance.