Epidemiology of adult obstructive sleep apnoea syndrome in India.

There is a paucity of published Indian studies on the prevalence and risk factors of obstructive sleep apnoea (OSA) in adults. The limited published literature, however, does not suggest significant differences in the prevalence and risk factors for OSA and obstructive sleep apnoea syndrome (OSAS) as compared to western studies. Well designed studies are required from all parts of India. Patients should be screened carefully before referring them to costly investigations such as overnight polysomnography. With the background of increasing urbanization, fast growing economy and changes in lifestyle, India will have an epidemic of obesity. Therefore, future studies on the association of OSA and metabolic syndrome should carefully evaluate confounding effect of obesity on metabolic abnormalities in patients with OSA.

Effect of antituberculosis treatment on cardiopulmonary responses to exercise in miliary tuberculosis.

BACKGROUND & OBJECTIVES: Tuberculosis (TB) is a major health problem in the developing world. In this preliminary study, we report the effect of antituberculosis treatment (ATT) on cardiopulmonary responses to exercise in patients with miliary tuberculosis (MTB). METHODS: The prospective study of cardiopulmonary responses to exercise in patients with MTB within one month of starting (n=14), on completion of ATT (n=7) and in 15 healthy subjects using the incremental exercise test was performed on a bicycle ergometer. RESULTS: In MTB patients, mean body mass index (BMI), exercise duration (3.1 vs 4.6 min), work load (63 vs 91.4 watts), resting tachycardia, tachypnoea and the mean oxygen saturation improved significantly (P<0.05) with ATT. Mean oxygen consumption (V . O(2)) at anaerobic threshold (546.7 vs 580.9 ml/min) and maximum exercise (1008.1 vs 1022 ml/min) were similar before and after ATT. In MTB patients, post-treatment mean body weight, BMI, resting heart rate, respiratory rate and oxygen saturation during maximum exercise were similar, but exercise duration (4.6 vs 6.2 min, P<0.05), work load (91.4 vs 145.5 watts, P<0.05), V . O(2) and oxygen pulse were significantly lower as compared to healthy subjects. INTERPRETATION & CONCLUSION: In MTB patients, though there was significant improvement in clinical parameters, functional abnormalities persisted on exercise testing after completion of ATT. As most patients with MTB are young and economically active, these observations obviously have long-term implications for these individuals.

Outdoor air pollution and emergency room visits at a hospital in Delhi.

Several reports from large metropolitan cities have indicated significant association between acute morbidity and mortality from cardio-respiratory disorders and daily levels of major pollutants in the ambient air. Despite the wide-spread public concern about the adverse health effects of air pollution, there is substantial uncertainty regarding the effects of these pollutants at a concentration typical of Delhi, which is one of the ten most polluted cities in the world and the most polluted city in India. This study was undertaken to correlate the daily levels of various pollutants with the number of patients visiting the All India Institute of Medical Sciences (AIIMS, New Delhi) casualty for aggravation of certain defined cardiorespiratory disorders. Daily counts of patients visiting the emergency room of the AIIMS for acute asthma, acute exacerbation of chronic obstructive airway disease (COAD) and acute coronary event was obtained in prospective manner from January 1997 to December 1998. Daily mean levels of ambient CO, NOx and SO2 were monitored along with temperature and humidity. Data was analysed using one day time lag for events of interest. Time series analysis was undertaken using Poisson regression and population averaged general estimation equation, correcting for auto-correlation, days of the weak and season. The ambient levels of pollutants exceeded the national air quality standards on most of the days, over the two year period. Further, emergency room visits for asthma, COAD and acute coronary events increased by 21.30%, 24.90% and 24.30% respectively on account of higher than acceptable levels of pollutants. It is concluded that there is considerable burden of cardiorespiratory diseases in Delhi due to high levels of ambient air pollution.