Treatment Efficacy
In AZA group, 10 patients discontinued their treatment before 6 months and four patients had incomplete data, leaving 43 patients for the final analysis. Seven patients in CYC group had missing data and 72 patients were included in the final analysis . Treatment outcomes are summarized in Table 2. Despite favorable baseline parameters, those who received AZA for induction therapy were significantly more likely to progress in 6 months, in terms of MMRC scores and regression of intensity of reticulation on HRCT, as well as % predicted FVC. CYC treatment resulted in 2.41 % increase in FVC, however AZA resulted in 1.44% decline in FVC predicted (p=0.041). These findings remained consistent after adjustment for age, gender and HRCT pattern, CTD diagnosis, smoking status, corticosteroid use, disease extent and duration of symptoms. Progression was more frequent in AZA group across all disease subtypes. After adjusting for potential confounding factors (age, disease subtype and basal FVC), a multivariate regression model was created. The analysis showed that CYC treatment was associated with decreased risk of progression compared to AZA treatment (HR: 0.18 (95 % CI 0.05 to 0.542)). Propensity score was used to explain the differences between patient groups receiving AZA and CYC. The variables used in the calculation for patients are: age, gender, smoking status, pre-treatment FVC percent and disease subtype (SCL / non-SCL). According to the propensity score matching status, a total of 65 patients, 28 AZA and 37 CYC, were selected.After this calculation AZA treatment was related to increased risk of progression compared to CYC treatment (HR: 6.75 (95 CI %, 1.97 to 23.12))