Hospitalization Risk for Medicare Beneficiaries With Nontuberculous Mycobacterial Pulmonary Disease

Background: Nontuberculous mycobacterial pulmonary disease (NTM-PD) is an uncommon mycobacterial infection characterized by worsening lung function and increased health care resource utilization; however, the overall risk for hospitalization among patients with NTM-PD remains unclear.

Research Question: What is the hospitalization risk among older adults with NTM-PD?

Study Design And Methods: A retrospective, nested, case-control study was conducted by using the Medicare claims database. Cases were defined as patients with ≥ 2 NTM-PD claims ≥ 30 days apart between January 1, 2007, and December 31, 2015. The study included individuals aged ≥ 65 years with ≥ 12 months of continuous enrollment in both Parts A and B before the first NTM-PD diagnosis. Cases were matched 1:2 to Medicare beneficiaries without NTM-PD (control subjects) according to age and sex. Hospitalizations following the first NTM-PD claim were compared between case and control subjects by using univariate and multivariate analyses.

Results: A total of 35,444 case subjects and 65,467 matched control subjects (mean age, 76.6 years; 70% female; ≥ 87% White) were identified. Baseline comorbidities, particularly pulmonary comorbidities, were more common in case subjects than in control subjects (81.1% vs 17.7% for COPD; 44.6% vs 0.6% for bronchiectasis). All-cause hospitalization was observed in 65.7% of case subjects and 44.9% of control subjects. Unadjusted annual hospitalization rates were significantly (P < .05) greater among case subjects than control subjects. Case subjects also had a significantly shorter time to hospitalization than control subjects. The increased burden due to hospitalization was reflected in multivariate analysis adjusting for baseline comorbidities. All-cause hospitalization in patients with NTM-PD relative to control subjects was 1.2 times more likely (relative risk, 1.23; 95% CI, 1.21-1.25; P < .0001) with a 46% greater hazard (hazard ratio, 1.46; 95% CI, 1.43-1.50; P < .0001).

Interpretation: Patients with NTM-PD were significantly more likely to be hospitalized, had greater annualized hospitalization rates, and had shorter time to hospitalization than age- and sex-matched control subjects without NTM-PD. These findings highlight the significantly increased burden of hospitalizations among patients with NTM-PD.