Impact of obesity on bronchial asthma in Indian population

Obesity and asthma are common inflammatory conditions, having presence of both local and systemic inflammation and this relationship is not well understood. This study was undertaken to compare pulmonary function parameters, inflammatory marker like C-reactive protein (hs-CRP), exhaled nitric oxide (FENO) and atopic profile between non-obese and obese bronchial asthma patients in Indian population. The study aims to elucidate the association between the systemic and local inflammatory response relating to obesity in asthmatics.

Sixty bronchial asthma patients were recruited for the study, and were divided equally into obese (BMI>30 kg/m(2)) and non-obese (BMI<25 kg/m(2)) groups. These were assessed for pulmonary function parameters, blood hs-CRP levels, exhaled breath analysis of nitric oxide and skin prick testing for atopic profile. The study was approved by institutional ethical committee.

The mean body mass index (BMI) for the non-obese and obese group was 21.64 kg/m(2) and 34.1 kg/m(2) respectively (P = 0.001). The functional residual capacity (FRC% predicted) (100.9 ± 4.21 vs 80.40 ± 4.03; P = 0.009) and expiratory reserve volume (ERV% predicted) (95.13 ± 6.71 vs. 67.03 ± 4.54; P = 0.001) both were significantly lower in the obese group. The non-obese and obese group had hs-CRP levels of 3.01 mg/L and 4.07 mg/L, respectively; the difference being statistically insignificant (P = 0.15). Similarly, FENO levels of non-obese and obese group were 63.20 ppb and 63.75 ppb, respectively; difference was not statistically significant (P = 0.95). Atopic profile of both the groups did not differ significantly.

Obesity does not appear to increase the local and systemic inflammatory responses in bronchial asthma patients in Indian population.