OBJECTIVES: The study compared healthcare insurance spending between treatment groups in patients with nontuberculous mycobacterial lung disease (NTMLD) from a US national managed care claims database.

METHODS: Patient (N=1039) pharmacy claims at year 1 following NTMLD diagnosis were classified into 3 treatment groups including triple combo (macrolide + ethambutol + rifamycin ± other drugs) (G1), other antibiotics for NTMLD (G2), and no treatment (G3). Healthcare insurance spending at year 2 was compared between treatments with adjustment for lung infection due to mycobacterium abscessus and cystic fibrosis, and for Charlson Comorbidity Index (CCI) during the 12 months prior to NTMLD diagnosis (baseline). Insurance spending was measured by allowed payment amounts and converted to Resource-Based Relative Value Scale (described elsewhere).

RESULTS: Mean age was 66, 66 and 73 years with 65%, 70% and 66% women in G1 (n=353), G2 (n=388) and G3 (n=298) respectively. At baseline, there was no difference on CCI (CCI≈2) between treatment groups. However, comorbidity distribution differed prominently in asthma (22.1%, 26.3% and 11.4%), arrhythmia (19.3%, 19.3% and 27.2%), cystic fibrosis (0.8%, 4.6% and 0%), immune disorder (7.6%, 9% and 2.7%), pneumonia (49.0%, 41.8% and 32.6%), and tuberculosis (9.3%, 8.2% and 5.4%), and in immunosuppressant use (51%, 51.5% and 25.2%). Mean (median) baseline total insurance payment was $32950($18067) in G1, $44507($18405) in G2, and $25555($10576) in G3. At year 2, CCI stayed almost unchanged and total payments were $26906($11638), $38130($13995) and $19449($7682), respectively. Compared to G2, adjusted total insurance payment was lower in G1 (δ=-$49838, 95%CI: -86576 to -13101, p=0.008) and G3 (δ=-83567, 95%CI: -131471 to -35663, p<0.001); but no statistically significant difference was found between G1 and G3.

CONCLUSIONS: Healthcare insurance spending was higher in patients with NTMLD and treated with drug regimens other than ATS/IDSA recommended triple therapy. Spending in patient comorbidity subgroups will be further investigated.