This clinical study was done to compare autonomic dysfunction in asthmatics by 6 non-invasive tests, to compare autonomic dysfunction in asthmatics and controls, to determine the relationship of duration of asthma with autonomic dysfunction and to compare the severity of asthma with autonomic dysfunction.
The selected patients were divided into 2 groups. Group 1 (cases)-included cases of bronchial asthma. Group 2 (controls)-comprising of age and sex matched normal subjects. The severity of asthma was defined in terms of mild intermittent, mild persistent, moderate and severe asthma based on the symptoms, variability of peak expiratory flow rate (PEFR) and frequency of use of beta-2 agonists. Tests used for the diagnosis of autonomic dysfunction were: 1. Orthostatic test, 2. 30:15 ratio, 3. Sustained hand grip test, 4. Deep beathing test, 5. Atropine test and, 6. Valsalva maneuver.
Out of 30 patients, 22 had autonomic dysfunction whereas 8 had normal function. Eight patients had asthma duration of less than 5 years out of which only 2 had autonomic dysfunction. Majority of the patients with autonomic dysfunction (20 patients) had bronchial asthma of duration greater than 5 years. Severe asthma was present in 16 patients out of 30, out of which 15 patients had demonstrable autonomic dysfunction. Mild-moderate asthma was present in 14 patients, out of which 7 had autonomic dysfunction. Overall, out of 30 asthma patients enrolled in the study, 14 had pure parasympathetic dysfunction, 12 had both parasympathetic and sympathetic dysfunction and 4 had isolated sympathetic dysfunction.CONCLUSIONS: Our study shows that asthmatics display definite autonomic dysfunction compared to controls. More the duration of asthma, more is the incidence of autonomic dysfunction. As the severity of asthma increases, the incidence of autonomic dysfunction also increases.
Autonomic dysfunction is present in asthma patients with increasing duration and severity. Parasympathetic hyper responsiveness may contribute to severity of asthma exacerbations and anticholinergic drugs may be useful in managing this condition.
B. Sharma, None.