ICMR's Insearch: The burden of lung diseases on Hyderabadis, other Indians
2011 Syed Akbar Hyderabad, March 28: Contrary to popular perception, the prevalence of asthma and chronic bronchitis is quite low in the twin cities of Hyderabad and Secunderabad. The burden of chronic respiratory diseases is relatively lower for a major urban area like Hyderabad. The phase II of the Indian study on epidemiology of asthma, respiratory symptoms and chronic bronchitis (Insearch), carried out by the Indian Council of Medical Research across 12 important cities including Hyderabad, revealed that only 0.37 per cent of people in twin cities suffer from asthma, as against the national average of 2.02 per cent. It was as high as 4.45 per cent in rural Thiruvanantapuram. The other cities covered under the ICMR study for a first hand scientific assessment of the overall burden of chronic respiratory diseases among Indians, were Ahmedabad, Berhampur, Bikaner, Chennai, Guwahati, Kolkata, Mumbai, Mysore, Nagpur, Shimla, and Thiruvanantapuram. In case of chronic bronchitis, Hyderabad has the least percentage among women, less than one per cent. For men and women combined, it's less than 2 per cent. But it's as high as 13.54 per cent in Thiruvanantapuram as against the national average of 3.49 per cent for chronic bronchitis. "Chronic respiratory disease or CRD is one of the most common cause of disease burden in India. CRD includes asthma and chronic obstructive pulmonary disease, which together may account for an estimated burden of about 100 million individuals in India," said Dr R Vijai Kumar, senior pulmonologist, Yashoda Hospitals, who served as the principal investigator for Hyderabad in the ICMR study. Dr Vijai Kumar attributed the high incidence of chronic respiratory diseases in places like Thiruvanantapuram to presence of pollen in air in large quantities and high salinity winds. "Hyderabad is a major referral centre and people from all parts of the State visit hospitals here. Since we take people from other areas too into account, we feel that the incidence of asthma is high in Hyderabad. In this study we selected only the residents," he pointed out. Significantly more number of asthmatics had a first degree relative with asthma, as compared to nonasthmatics, at all places including Hyderabad. On univariate analysis, the odds of having asthma were 2.36 to 19.59 fold higher for those with such family history in different cities. Also, the odds of having asthma were significantly increased among neversmokers thus exposed in Ahmedabad, Bikaner, Chennai, Guwahati, Secunderabad and Thiruvanantapuram. Childhood exposure to tobacco smoke alone was associated with higher odds of asthma at Ahmedabad, Berhampur and Guwahati, and adulthood exposure alone was associated with higher odds of asthma at Chennai, Guwahati, Mysore, Secunderabad, Shimla and Thiruvanantapuram. Regular cooking using coal at Berhampur, using LPG, wood or dung cake at Bikaner, using wood at Guwahati, using dung cakes at Bikaner, and using LPG at Hyderabad-Secunderabad, were associated with higher odds of chronic bronchitis.