Risk factors for mortality among tuberculosis patients on treatment at Bugando Medical Centre in north-western Tanzania: a retrospective cross-sectional study

Background: Tuberculosis (TB) is still an important cause of morbidity and mortality worldwide. Though it can effectively be treated, still a significant proportion of patients die on the course of their treatment. The objective of this study was to determine the outcome and risk factors of mortality among patients diagnosed with TB in a tertiary hospital in north-western Tanzania. Methods: A retrospective cross sectional study was done among all patients diagnosed with TB between January and December 2015 at Bugando Medical Centre. Information of demographic characteristics, smear positivity, haemoglobin concentration, HIV status, CD4 counts for HIV positive patients and treatment outcomes were collected and analysed. TB treatment outcomes as dead or alive were calculated and logistic regression was done to determine the factors associated with increased risk of death of patients on anti-TB treatment. Results: In total 701 patients were diagnosed with TB during the study period. Of these, 361 (51.5%) were males with a median age of 38 (IQR 27- 47) and 421 (60.06%) were younger than 40 years. Majority of the participants 409 (58.35%) had smear positive pulmonary tuberculosis and about half of patients (51.07%) tested positive for HIV. Of the enrolled patients 610 (87.02%) were alive at the end of TB treatment while 91 (12.98%) died in the course of treatment. The odds of deaths of patients on anti-TB treatment were strongly associated with male sex, HIV co infection and severe anaemia. Conclusion: The proportion of patients who die from TB treatment at BMC is high, with an increased risk of death among HIV co-infected, older than 40 years and severely anaemic patients. Improvement of strategies for early diagnosis and prompt treatment of TB patients will potentially improve treatment outcome.