Prognostic Factors of 634 HIV-Negative Patients with Mycobacterium avium Complex Lung Disease

Rationale: The prognostic factors of Mycobacterium avium complex lung disease (MAC-LD) are not clearly defined. Objectives: To assess the prognostic factors of all-cause and MAC-specific mortality in patients with MAC-LD, especially in accordance with radiographic features, first-line treatment, and host predisposition. Methods: Medical records of 634 HIV-negative patients with MAC-LD treated at our institution in Saitama, Japan were retrospectively analyzed. Measurements and Main Results: Patients' mean age was 68.9 years, and median follow-up period was 4.7 years. Radiographic features included nodular/bronchiectatic (NB) disease: 482 patients (76.0%); fibrocavitary (FC) disease: 105 patients (16.6%); FC+NB disease: 30 patients (4.7%); and other types: 17 patients (3.0%). First-line treatments were observation or one drug: 479 patients (75.6%); 2 to 5 drugs: 131 patients (20.7%); and unknown: 24 patients (3.8%). A multivariate Cox proportional hazard model showed male sex, older age, presence of systemic and/or respiratory comorbidity, non-NB radiographic features, body mass index (BMI) less than 18.5 kg/m(2), anemia, hypoalbuminemia, and erythrocyte sedimentation rate greater than or equal to 50 mm/h to be negative prognostic factors for all-cause mortality, and FC or FC+NB radiographic features, BMI less than 18.5 kg/m(2), anemia, and C-reactive protein greater than or equal to 1.0 mg/dl to be negative prognostic factors for MAC-specific mortality. Conclusions: The first-line treatment regimen was not associated with all-cause mortality. FC or FC+NB disease, BMI less than 18.5 kg/m(2), and anemia were negative prognostic factors for both all-cause and MAC-specific mortality.