OBJECTIVES: Previous research has reported nontuberculous mycobacterial lung disease (NTMLD) prevalence of 47 per 100,000 among US Medicare beneficiaries ≥65 years in 2007, with an average increase of 8.2% annually between 1997 and 2007. In this study, we have evaluated NTMLD incidence and prevalence in Medicare between 2008 and 2015.

METHODS: Patients diagnosed for NTMLD with an ICD9 031.0 were identified from the Medicare database (N≈30 million yearly), not including the Part C portion. Individuals who incurred at least 2 medical claims ≥30 days apart between 2007-15 were considered as a positive NTMLD case, yielding 58,294 patients. All individuals fulfilling the case definition each calendar year were considered as prevalent cases. Incident cases included those meeting the case definition each year and having no medical claim for NTMLD in the prior year.

RESULTS: Patients with NTMLD in the US Medicare database had a mean age of 74 (±10) years. Sixty-nine percent were women and 89% white. Yearly NTMLD incidence increased from 20.7 (95% CI: 20.2-21.3) in 2008 to 28.1 (27.5-28.7) in 2013 per 100,000 Medicare beneficiaries and leveled to 27.6 (26.9-28.2) in 2014 and 25.9 (25.3-26.5) in 2015 per 100,000. Yearly NTMLD prevalence increased from 41.6 (40.9-42.3) in 2008 to 63.1 (62.2-64.0) in 2015 per 100,000 Medicare beneficiaries. In 2015, incidence was 28.1 vs 14.7 per 100,000 Medicare beneficiaries ≥65 years vs those <65 years, respectively. Prevalence was 70.2 vs 27.9 per 100,000 Medicare beneficiaries ≥65 years vs those <65 years, respectively. Incidence and prevalence were 33.9 vs 16.0/100,000 and 86.2 vs 34.6/100,000 in women vs men and 41.1 vs. 27.6/100,000 and 89.4 vs. 68.7/100,000 in beneficiaries of Asians vs White origin.

CONCLUSIONS: In US Medicare beneficiaries, NTMLD incidence increased from 2008 through 2013 and leveled off in 2014 and 2015, while NTMLD prevalence continued to rise through 2015.