Association of treatment interruption with sputum conversion and outcomes in drug-sensitive and drug-resistant tuberculosis patients enrolled under NTEP-a prospective study from 3 centers in South Delhi, Delhi, India.

BACKGROUND AND OBJECTIVES: Interruption of treatment is a vital challenge which threatens successful tuberculosis (TB) control. We studied the association of interruption patterns with sputum conversion and outcome in a cohort of confirmed pulmonary TB cases.

METHODS: In this observational prospective study, we recorded the various patterns of interruption [short-term or long-term] as per the protocol. Next, their association with smear conversion and the final outcome (in CAT-I and II patients); and that with culture conversion and the interim outcome at six months (in patients with extensively drug-resistant (XDR-TB) and multidrug-resistant (MDR-TB) tuberculosis) was evaluated.

RESULTS: The percentage of successful outcomes was considerably greater for patients with no interruptions under CAT-I and II (95 %), in comparison to those with interruption (70 %) [p = 00.0009]. In cases who had short-term interruptions in Intensive Phase (IP), smear negativity by end of IP was less (30.7 %), as compared to patients without short-term IP interruptions (84.5 %) [p = 0.001]. Long-term IP phase interruptions were significantly associated as an independent risk factor for final outcome in the CAT-I and II sub-group [p = 0.001]. Successful interim outcome in MDR and XDR-TB sub-group was better in subjects who had no interruptions (84 %), in contrast to those who interrupted treatment (47 %) [p = 0.018], while long term interruptions were also statistically associated to interim outcome of culture conversion by 6 months of ATT [p = 0.00026].

CONCLUSIONS: Interrupting treatment is a matter of concern, and its patterns should be periodically studied in detail to guarantee compliance with the provided treatment.