RESUMEN
Introduction: Increased parasympathetic drive in asthmatics is observed by many researchers. However, some have found increased sympathetic activity and others found it decreased.Materials and Methods: A case–control study was planned including 30 asthmatic patients and 30 age-matched non-asthmatics as controls. Spirometry and autonomic functions were tested, and results of the mean difference were compared using the Student t-test.Results: Out of 30 asthmatics, 76% were in mild-to-moderate grade of asthma on the basis of their forced expiratory volume in the first second % values. Rise in diastolic blood pressure with cold pressor test was significantly less in asthmatics than controls (5.66 ± 3.415 and 11.73 ± 4.49 mmHg; P < 0.001). The mean Valsalva ratio in asthmatics was significantly less than in controls (1.158 ± 0.116 and 1.418 ± 0.645; P < 0.05). Galvanic skin resistance in asthmatics was significantly more than in controls (589.8 ± 268.12 and 328.75 ± 165.07; P < 0.001).Conclusions: Thus, from our study, there was increased parasympathetic and decreased sympathetic drive in patients with bronchial asthma as compared to controls