Association of Clonal Hematopoiesis with Chronic Obstructive Pulmonary Disease.

Chronic obstructive pulmonary disease (COPD) is associated with age and smoking, but other determinants of the disease are incompletely understood. Clonal hematopoiesis of indeterminate potential (CHIP) is a common, age-related state in which somatic mutations in clonal blood populations induce aberrant inflammatory responses. Patients with CHIP have an elevated risk for cardiovascular disease, but the association with COPD remains unclear. We analyzed whole-genome and exome sequencing data to detect CHIP in 48,835 subjects, of whom 8,444 had moderate-to-very-severe COPD, from four separate cohorts with COPD phenotyping and smoking history. We measured emphysema in murine models in which Tet2 was deleted in hematopoietic cells. In COPDGene, individuals with CHIP had a risk of moderate-to-severe and severe or very severe COPD 1.6 and 2.2 times greater than non-carriers, respectively (adjusted 95% confidence intervals [CI], 1.1 to 2.2 and 1.5 to 3.2). These findings were consistent observed in three additional cohorts and meta-analyses of all subjects. CHIP was also associated with decreased FEV1% predicted in COPDGene (mean between group difference -5.7%; adjusted 95% CI, -8.8 to -2.6), a finding replicated in additional cohorts. Smoke exposure was associated with a small but significant increased risk of having CHIP (OR 1.03 per ten pack-years, 95% CI 1.01-1.05) in the meta-analysis of all subjects. Inactivation of Tet2 in mouse hematopoietic cells exacerbated emphysema development and inflammation in cigarette smoke exposure models. Somatic mutations in blood cells are associated with the development and severity of COPD, independent of age and cumulative smoke exposure.