Discontinuation rates attributed to adverse events and treatment outcomes between clarithromycin and azithromycin in Mycobacterium avium complex lung disease: A propensity score analysis

Objectives: This study aimed to compare the discontinuation rates attributed to adverse events and treatment outcomes between clarithromycin (CLR) and azithromycin (AZM) in patients with Mycobacterium avium complex lung disease (MAC-LD). Methods: Among patients diagnosed with MAC-LD during 2001–2013, 560 for whom treatment was initiated as a guideline-based therapy until May 2018 were selected for adverse event analysis. Of them, 316 who underwent treatment for ≥12 months were selected for outcome analysis. Their medical records were retrospectively reviewed. The discontinuation and treatment success rates were analysed after adjustments using the inverse probability of treatment weighted (IPTW) method. Results: Among the 560 patients, 466 (83.2%) and 94 (16.8%) started CLR-containing and AZM-containing regimens, respectively. The IPTW method using propensity scoring revealed that the discontinuation rate attributed to adverse events was significantly higher with CLR than AZM use (24.6% vs. 9.6%; P = 0.001). The overall treatment success rate of the 316 patients who received guideline-based therapy for ≥12 months was 83.2%. Analysis adjusted by the IPTW method showed no significant difference in the treatment success rate between the use of CLR and AZM. Furthermore, 1-year and 3-year recurrence rates were similar with the two drugs (6.8% vs. 6.0%; P > 0.999 and 31.0% vs. 37.5%; P = 0.482, respectively). Conclusions: These findings suggest that an AZM-containing regimen may be the better initial treatment choice for MAC-LD as it resulted in lesser discontinuation rates attributed to adverse events while offering similar patient outcomes when compared with CLR.