Introduction: In light of recent outbreaks of multidrug resistant tuberculosis (MDRTB) in London and increasing concerns about drug resistant tuberculosis worldwide there is a need to understand the epidemiology of drug resistant tuberculosis in this country. We describe a case control study of risk factors for drug resistance. Data collection is ongoing. Methods: Subjects were drawn from the MYCOBNET database (the UK reference laboratory reporting system for tuberculosis). Cases (n=306 ) were all culture confirmed cases of tuberculosis with resistance to either isoniazid (H) or (R) (or both) from England and Wales in 1993/4. 306 controls with fully sensitive tuberculosis were selected. Data on risk factors was obtained from surveillance information, Consultants in Communicable Disease Control and clinicians Data on HIV infection was obtained by matching the MYCOBNET dataset with the HIV/AIDS datasets at the PHLS AIDS Centre, Logistic regression analysis was used to calculate odds ratios (OR) and 95% confidence intervals (95% CI) controlled for confounders. Results: Independent risk factors for drug resistance included:- Ethnicity - Indian subcontinent ethnic group (OR 2.3, (95% CI-1.3-4.1) and black African ethnic group (OR 2.2 (1.0-4.4) p = 0.01);. previous treatment (OR 3.1 (1.8-5.3) p<0.0001), HIV (OR 4.3 (1.9-9.8)p=0.0003; chronic illness (OR 2.9 (CI 1.0-8.5) p=0.04) and residence in London (OR 1.7 (1.2-2.5)p=0.006) Drug resistance was more common in younger adults and more recent immigrants Independent risk factors for multidrug resistant tuberculosis (resistance to H and R with or without other drugs) (n=56) were male gender (OR 2.2 (1.1-4.3) p= 0.024); birth in India (OR 4.6 (1.2-18.1); previous treatment (OR 11.7 (5.5-25) p<0.0001); HIV (OR 8.9 (2.1-38.7) p=0.003) and residence in London (OR 4.0 (1.7-9.3) p=0.001).Both resistant and multidrug resistant patients were more likely to remain culture positive for more than one year (OR 11.8 (3.1-44.3) and 17.7 (3.7-84.3) respectively. Discussion: The results highlight those groups in whom drug resistance should be suspected.
|Issue number||SUPPL. 3|
|Publication status||Published - Dec 1996|