Objective We aimed to measure the mortality rate and excess general mortality as well as identify groups at high risk for mortality among a cohort of tuberculosis patients treated in Chennai Corporation clinics in south India. Methods In this retrospective cohort study we followed up 2674 patients (1800 males and 874 females) who were registered and treated under the DOTS strategy in Chennai Corporation clinics in 2000. The follow-up period from the date of start of treatment to either the date of interview, or death was 600 days. Findings The mortality rate among this cohort of tuberculosis patients was 60/1000 person-years. The excess general mortality expressed as standardized mortality ratio (SMR) was 6.1 (95% confidence interval (CI) = 5.4-6.9). Younger patients, men, patients with Category II disease, patients who defaulted on, or failed courses of treatment, and male smokers who were alcoholics, all had higher mortality ratios when compared to the rest of the cohort. Conclusion The excess mortality in this cohort was six times more than that in the general population. Young age, male sex, smearpositivity, treatment default, treatment failure and the combination of smoking and alcoholism were identified as risk factors for tuberculosis mortality. We suggest that mortality rate and excess mortality be routinely used as a monitoring tool for evaluating the efficiency of the national control programme.Bulletin of the World Health Organization 2006;84:555-560.Voir page 559 le résumé en français. En la página 560 figura un resumen en español.
IntroductionTuberculosis (TB) is a major public health problem in India and most of the disease burden is due to premature mort t tality among TB patients.1 Mortality is measured either as true rate (personttime rate) or as risk of death within a specific time period of followtup (casetfatality rate). The casetfatality rate is the more commonly used mortality measure of the two. However, casetfatality rates among TB patients reported in the literature range from 12% to 44% and are not comparable because they were measured as cumulative incidence for different followtup periods.2-8 Risk factors such as smoking, alcoholism, irregular and incomplete antittuberculosis treatment as well as HIV infection are known to increase the mortality associated with TB. 2,4,5,7,9 WHO defines TB mortality as the number of TB cases dying during treatt t ment, regardless of the cause.10 This definition, however, does not reflect the actual TB mortality rate because it includes deaths due to cotmorbidities and accidents, excludes deaths among treatment defaulters who have a high risk for mortality and presupposes that TB mortality does not occur after the completion of treatment. A better, though indirect, measure of mortality would be the computation of excess mortality (or standardized mortality ratio (SMR)) occurring among TB pat t tients and comparing it to the mortalt t ity among the standard population (or the estimated national population for a certain year). Since 1999, the Chennai Cor...