Risk Factors Associated with Survival of Pulmonary Tuberculosis

  • Mehdi KAZEMPOUR DIZAJI Dept. of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
  • Anoshirvan KAZEMNEJAD Mail Dept. of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
  • Payam TABARSI Mycobacteriology Research Center, National Research Institute for Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran Clinical Tuberculosis and Epidemiology Research Center, National Research Institute for Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Farid ZAYERI Dept. of Biostatistics, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Tuberculosis, Generalized gamma regression model, Pulmonary TB



Background: We conducted this study among adults with pulmonary tuberculosis (TB) who received treatment, in order to determine the risk factors associated with survival of during treatments.

Methods: A retrospective cohort study was conducted from 2005-2015 with newly registered TB patients in the Hospital of Masih Daneshvari Doctor, Tehran, Iran. Overall, 5313 patients met our study's cohort definition, but the analysis was performed on 2299 patients (43.2%) who had a correct address and they could be traced-out by the Medical – registry. Time in days was used in survival model and patients who were still alive (until last follow-up date) considered as censored. To study the effect of risk factors on patients’ survival, the generalized gamma regression model was used.

Results: Based on the results of univariate analysis, gender (RR=2 (95% CI: 1.1−3.7), high school education (Relative Risk: RR=0.3 (95% CI: 0.2−0.7), higher education (RR=0.3 (95% CI: 0.1−0.9), smoker (RR=2.5 (95% CI: 1.4−4.2), drug user (RR=2.4 (95% CI: 1.4−4), TB contact (RR=0.5 (95% CI: 0.3−0.8) and HIV positive (RR=4 (95% CI: 1.7−9.2) affected patients’ survival. Moreover, the results of multivariate analysis showed that, gender (RR=5.5 (95% CI: 2.2−13.5), age (RR=1.1 (95% CI: 1−1.1), adverse drug effect (RR=2.5 (95% CI: 1.2−5.4), smoker (RR=3.3 (95% CI: 1.2−9.4), TB contact (RR=0.2 (95% CI: 0.1−0.5), diabetic mellitus (RR=3 (95% CI: 1−8.3), HIV positive (RR=26 (95% CI: 4.6−145.9) and comorbidities (RR=4.9 (95% CI: 2−11.6) were identified as factors affecting patients’ survival.

Conclusion: Our data indicated associated risk factors in TB mortality and could suggest way to progressing national tuberculosis program (NTP) for predicating and plan for effective interventional strategies.



Glaziou P, Sismanidis C, Floyd K, Raviglio-ne M (2015). Global epidemiology of tu-berculosis. Cold Spring Harb Perspect Med, 5(2): a017798.

Miller TL, Wilson FA, Pang JW et al (2015). Mortality hazard and survival after tuber-culosis treatment. Am J Public Health, 105(5):930-7.

Kwon YS, Kim YH, Song JU et al (2014). Risk factors for death during pulmonary tuberculosis treatment in Korea: a multi-center retrospective cohort study. J Korean Med Sci, 29(9):1226-31.

Wu YC, Lo HY, Yang SL et al (2015). Comparing the factors correlated with tuberculosis-specific and non-tuberculosis-specific deaths in different age groups among tuberculosis-related deaths in Taiwan. PLoS One, 10(3):e0118929.

Murray CJ, Ortblad KF, Guinovart C et al (2014). Global, regional, and national in-cidence and mortality for HIV, tuberculo-sis, and malaria during 1990-2013: a sys-tematic analysis for the Global Burden of Disease Study 2013. Lancet, 384(9947):1005-70.

Alavi-Naini R, Moghtaderi A, Metanat M et al (2013). Factors associated with mortali-ty in tuberculosis patients. J Res Med Sci, 18(1):52-5.

Torkaman MR, Nasiri MJ, Farnia P et al (2014). Estimation of Recent Transmis-sion of Mycobacterium Tuberculosis Strains among Iranian and Afghan Im-migrants: A Cluster-Based Study. J Clin Diagn Res, 8(9):DC05-8.

Klein JP, Moeschberger ML (2005). Survival analysis: techniques for censored and truncated da-ta.2 ed. Springer Science & Business Me-dia.

Kleinbaum D, Klein M (2011). Survival Anal-ysis: A self-learning text. 2nd ed. New York.

Kalbfleisch JD, Prentice RL (2011). The statis-tical analysis of failure time data 2ed. John Wiley & Sons.

Albuquerque MdFPM, Batista J.d.A.L, Xi-menes R.A.dA et al (2009). Risk factors associated with death in patients who ini-tiate treatment for tuberculosis after two different follow-up periods. Rev Bras Epi-demiol, 12(4):513-522.

Akessa, G. M., Tadesse, M., & Abebe, G. (2015). Survival Analysis of Loss to Fol-low-Up Treatment among Tuberculosis Patients at Jimma University Specialized Hospital, Jimma, Southwest Ethiopia. In-ternational Journal of Statistical Mechanics, 2015:923025.

Forrellad MA, Klepp LI, Gioffré A et al (2013). Virulence factors of the Mycobac-terium tuberculosis complex. Virulence, 4(1):3-66.

Fiske CT, Yan FX, Hirsch-Moverman Y et al (2014). Risk factors for treatment de-fault in close contacts with latent tubercu-lous infection. Int J Tuberc Lung Dis, 18(4): 421-7.

Guerra-Laso JM, González-García S, Gon-zález-Cortés C et al (2013). Macrophages from elders are more permissive to intracellular multiplication of Mycobacte-rium tuberculosis. Age (Dordr), 35(4):1235-50.

Girardi E, Antonucci G, Vanacore P et al (2004). Tuberculosis in HIV-infected per-sons in the context of wide availability of highly active antiretroviral therapy. Eur Respir J, 24(1):11-7.

Millet JP, Orcau A, Rius C et al (2011). Pre-dictors of death among patients who completed tuberculosis treatment: a population-based cohort study. PLoS One, 6(9): e25315.

Tabarsi P, Chitsaz E, Moradi A et al (2012). Treatment outcome, mortality and their predictors among HIV-associated tuber-culosis patients. Int J STD AIDS, 23(9):e1-e4.

Erhabor GE, Adewole OO, Ogunlade O (2006). A five-year review of tuberculosis mortality amongst hospitalised patients in Ile-Ife. Indian J Chest Dis Allied Sci, 48(4):253-6.

Babamahmoodi F, Alikhani A, Yazdani Charati J et al (2015). Clinical epidemiolo-gy and paraclinical findings in tuberculo-sis patients in north of Iran. Biomed Res Int, 2015:381572.

Lin CH, Lin CJ, Kuo YW et al (2014). Tu-berculosis mortality: patient characteristics and causes. BMC Infect Dis, 14:5.

Pachi A, Bratis D, Moussas G, Tselebis A (2013). Psychiatric morbidity and other factors affecting treatment adherence in pulmonary tuberculosis patients. Tuberc Res Treat, 2013:489865.

Wu YC, Lo HY, Yang SL, Chou P (2014). Factors correlated with tuberculosis re-ported after death. Int J Tuberc Lung Dis, 18(12):1485-90.

Oakes D (1983). Comparison of models for survival data. Stat Med, 2(2):305-11.

Vasantha M, Gopi P, Subramani R (2008). Survival of tuberculosis patients treated under DOTS in a rural Tuberculosis Unit (TU), south India. Indian J Tuberc, 55(2):64-9.

Oursler KK, Moore RD, Bishai WR et al (2002). Survival of patients with pulmo-nary tuberculosis: clinical and molecular epidemiologic factors. Clin Infect Dis, 34(6):752-759.

How to Cite
KAZEMPOUR DIZAJI M, KAZEMNEJAD A, TABARSI P, ZAYERI F. Risk Factors Associated with Survival of Pulmonary Tuberculosis. Iran J Public Health. 47(7):980-987.
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