Risk factors associated with death in patients who initiate treatment for tuberculosis after two different follow-up periods

Abstract

INTRODUCTION: Mortality from tuberculosis, which should be a rare event, still affects a large portion of the population of developing countries. In this context, Recife, a city in the northeast of Brazil where this study was developed, has the highest tuberculosis mortality rates of the Brazilian capitals. OBJECTIVE: To analyze survival probability and identify risk factors for death from tuberculosis in a cohort of patients living in Recife who started treatment for tuberculosis. METHODOLOGY: A cohort of newly diagnosed TB cases was followed up from the beginning of treatment (in 2001-2003) until June 2007. Survival probability was estimated by Kaplan-Meier method; and Cox Regression analysis was used to identify risk factors. RESULTS: At the end of the follow-up period, the survival probability after beginning TB treatment was 95.9%. Older ages, positivity for HIV and late initial treatment were statistically associated with death from TB in one year follow-up. When the analysis was done considering the total period of follow-up, older ages, positivity serology for HIV, late initial treatment, weight loss, and history of previous treatment remained in the multivariate Cox regression model. CONCLUSION: A more comprehensive analysis, specifically for deaths from tuberculosis as the underlying and non-underlying cause, allowed identification of a greater number of predictive factors that would otherwise not be detected if follow-up had lasted only until the end of treatment. These results can guide feasible interventions for health services aiming to reduce case-fatality from tuberculosis.

Adherence to Tuberculosis Treatment, Sputum Smear Conversion and Mortality: A Retrospective Cohort Study in 48 Rwandan Clinics

“…Not surprisingly, older TB patients had a higher risk of death [3], [26], [27]. Older people have a higher mortality rate anyway; underlying disease as a cofactor for TB is more common in older people and may explain the increased risk of death.…”

Application of Cox Proportional Hazards Model in Case of Tuberculosis Patients in Selected Addis Ababa Health Centres, Ethiopia

“…During follow up HIV-positive was statistically significant in the multivariable Cox regression model [14]. Also HIV coinfection was statistically associated with an increased risk of death in TB patients during treatment [5, 13, 15, 19].…”

“…However, studies by [12, 14, 20] reported that body weight at initiation of treatment was a risk factor for death from TB and is associated with survival of patients who begin treatment for tuberculosis.…”

Predictive factors of death in patients with tuberculosis: a nested case–control study

“…Similar to our findings, Millet et al (4) and Girardi et al (11) showed a mortality rate up to 10 times higher in HIVpositive patients compared to those without positive serology of HIV. Moreover, in studies conducted by Van den Broek et al (12) and Albuquerque et al (9), HIV positivity was reported as an important predictive factor of death from tuberculosis. Several factors, such as delays in diagnosis and treatment of HIV-positive patients whose sputum smear is usually negative, and also more advanced immunosuppression, can explain this poor outcome (7).…”