Environmental and Host-Related Factors Predisposing to Tuberculosis in Karachi: A Cross-Sectional Study
BACKGROUND: To study the environmental and host-related factors predisposing to tuberculosis (TB) in Karachi.
METHODS: This was a descriptive cross-sectional study, which was conducted at two tertiary care government hospitals. The duration of the study was from September 2009 to February 2010. A total of 250 sputum smear-positive TB patients were included in the study. A questionnaire containing information on age, sex, education and occupation was completed by two separate investigators from each setting. Recall information was elicited about the presence of co-morbidities, any form of addiction or immunosuppression, BCG vaccination and close contact with a tuberculosis patient.
RESULTS: Questionnaires were completed for 250 sputum smear-positive pulmonary TB patients. The mean duration of positive sputum TB was 5.39 (SD+4.76)
months. 54% patients were male. Diabetes had the maximum prevalence, with approximately 25% patients reporting to have diabetes. Most common addiction was smoking (48%), and 10% of the smokers belonged to the high-risk group (20 or more cigarettes per day). 69.6% patients (N=174) lived in over-crowded houses (≥3 persons/room).
CONCLUSIONS: Multiple environmental and host-related factors are present in the sputum smear-positive cases of Karachi. Thus, an understanding of these risk factors will contribute in the appropriate management of this disease.