Survival analysis of patients with tuberculosis in Erbil, Iraqi Kurdistan region

Background Tuberculosis is an important health concern in Iraq, but limited research has examined the quality of tuberculosis care and the survival of the patients. This study aimed to assess the 12-month survival of tuberculosis patients and evaluate the effect of the associated risk factors on patients' survival. Methods We reviewed the records of 728 patients with tuberculosis who were registered and treated at the Chest and Respiratory Disease Center in Erbil, Iraqi Kurdistan Region, from January 2012 to December 2017. Demographic data, the site of the disease, and treatment outcomes were retrieved from patients' records. Data analysis included the use of the Kaplan-Meier method and the log-rank test to calculate the estimates of the survival and assess the differences in the survival among the patients. The Cox regression model was used for univariate and multivariate analysis. Results The mean period of the follow-up of the patients was 7.6 months. Of 728 patients with tuberculosis, 50 (6.9%) had died. The 12-month survival rate of our study was 93.1%. A statistically significant difference was detected in the survival curves of different age groups (P < 0.001) and the site of the disease (P = 0.012). In multivariate analysis, lower survival rates were only observed among patients aged >= 65 years (hazard ratio = 9.36, 95% CI 2.14-40.95) and patients with extrapulmonary disease (hazard ratio = 2.61, 95% CI 1.30-5.27). Conclusion The 12-month survival rate of tuberculosis patients managed at the Chest and Respiratory Disease Center in Erbil was similar to the international rates. The high rates of extrapulmonary tuberculosis and the low survival rate necessitate further studies and action with a possible revision to the tuberculosis management strategy.