Abstract

Background: In India, Revised National Tuberculosis (TB) control programme (RNTCP) offers free diagnosis and treat- ment for TB, based on the Directly Observed Treatment Short (DOTS) course strategy. Under RNTCP, sputum conversion rate (SCR), at the end of 2 months of treatment is an important operational indicator, which is ideally expected to be 90%.
Objective: The objective of the present work was to investigate the factors associated with low SCR at the end of 2 months of treatment in Sira TB unit, Tumkur District, India. Material and Methods: It is a retrospective cohort study of all new sputum smear-positive patients registered in RNTCP in 2011. Data were retrieved from the TB register maintained at the District TB center. Chi-square and Student’s t-test were used for analysis of the study variables between patients who were sputum positive and sputum negative at the end of 2 months of treatment. Multivariate logistic regression was applied to determine the risk contributed by the variables towards non-conversion of sputum.
Results: Of the 268 included patients, 66.7% patients were sputum negative. Patients aged ≥ 45 years were twice the risk of being sputum positive (OR = 2.14) (P = 0.007). The odds of being sputum positive after 2 months of treatment was observed to be significantly high (OR = 7.12; 95% C.I. = 1.52–33.22; P = 0.01) for sputum grade 3+ at the time of diagnosis, respectively. Conclusion: Elderly patients with a high bacilli load should be advised and counselled well regarding adherence to treat- ment. Further advice should be given on preventing spread of the disease by practising cough hygiene, as they are more infectious than remaining patients with less sputum-positive grade.