Incidence and Prevalence of Nontuberculous Mycobacterial Lung Disease in a Large U.S. Managed Care Health Plan, 2008–2015

<b>Rationale:</b> Estimating the annual incidence and prevalence of nontuberculous mycobacterial (NTM) lung disease may assist in improving understanding of the public health and economic impacts of this disease and its treatment.<b>Objective:</b> To estimate the yearly incidence and prevalence of administrative claims-based NTM lung disease between 2008 and 2015 in a U.S. managed care claims database.<b>Methods:</b> We used a national managed care claims database (Optum Clinformatics Data Mart) representing a geographically diverse population of approximately 27 million members annually. All medical claims from January 1, 2007, to June 30, 2016, were scanned for diagnosis codes for NTM lung disease (<i>International Classification of Diseases, Ninth Revision, Clinical Modification</i> [ICD-9-CM] code 031.0 or ICD-10-CM code A31.0). We defined a case of NTM lung disease as having at least two medical claims with a code of 031.0 or A31.0 that were dated at least 30 days apart. Annual incidence and prevalence were estimated for each calendar year from 2008 to 2015.<b>Results:</b> From 2008 to 2015, the annual incidence of NTM lung disease increased from 3.13 (95% confidence interval [CI], 2.88-3.40) to 4.73 (95% CI, 4.43-5.05) per 100,000 person-years, and the annual prevalence increased from 6.78 (95% CI, 6.45-7.14) to 11.70 (95% CI, 11.26-12.16) per 100,000 persons. The average annual changes in incidence and prevalence were +5.2% (95% CI, 4.0-6.4%; <i>P</i> < 0.01) and +7.5% (95% CI, 6.7-8.2%; <i>P</i> < 0.01), respectively. For women, the annual incidence increased from 4.16 (95% CI, 3.76-4.60) to 6.69 (95% CI, 6.19-7.22) per 100,000 person-years, and the annual prevalence increased from 9.63 (95% CI, 9.08-10.22) to 16.78 (95% CI, 16.04-17.55) per 100,000 persons. For individuals aged 65 years or older, the annual incidence increased from 12.70 (95% CI, 11.46-14.07) to 18.37 (95% CI, 16.98-19.87) per 100,000 person-years, and the annual prevalence increased from 30.27 (95% CI, 28.41-32.24) to 47.48 (95% CI, 45.37-49.67) per 100,000 persons. The incidence and prevalence of NTM lung disease increased in most U.S. states and overall at the national level.<b>Conclusions:</b> The incidence and prevalence of NTM lung disease appears to be increasing in the United States, particularly among women and older age groups.