Abstract

Background: Sputum smear conversion rate (SCR) at the intensive phase (IP) of antitubercular treatment is an indicator of patient’s response to treatment as well as the performance of tuberculosis (TB) control program, especially in resource- limited settings. Objectives: The objectives of this study are (1) to identify medicosocial factors associated with a delay in sputum smear conversion at the end of IP and (2) to find the influence of sputum smear conversion on treatment outcome.
Materials and Methods: A prospective study was conducted in all six Designated Microscopy Centers (DMCs) of Davangere TB Unit, Karnataka, for 1 year. About 216 new sputum smear-positive pulmonary TB patients aged ≥15 years who were diagnosed in these DMCs and registered under Revised National TB Control Program constituted the study sample. Data were collected by direct interview method using a pretested, semistructured questionnaire.
Results: Majority of the study subjects were males, residing in urban areas. The overall sputum SCR was 85.8%. Univariate analysis revealed that elderly age, stigmatization, tobacco smoking, diabetes mellitus, and pretreatment sputum smear grading were significantly associated with delayed sputum smear conversion at the end of IP. In multivariate analysis, tobacco smoking (adjusted odds ratio [aOR] [95% confidence interval + (CI)]: 2.18 [1.03-4.61]), diabetes mellitus (aOR [95% CI]: 3.43 [1.27-9.31]), and higher pretreatment smear grading of 3 (aOR [95% CI]: 2.73 [1.27-5.85]) emerged as independent predictors of delayed sputum smear conversion. Delayed sputum smear conversion was also found to be significantly linked with unfavorable treatment outcomes. Conclusion: Sputum SCR among new smear-positive pulmonary TB patients in Davangere TB Unit was satisfactory. Patients with identified risk factors were less likely to achieve sputum smear conversion and need to be monitored more closely to prevent unfavorable outcomes.