Background: Most of our COPD knowledge comes from studies of older individuals. We must examine milder disease in younger patients if we are to better understand COPD pathogenesis.

Aim: Describe the respiratory disease burden among young and middle-aged adults at risk for or with COPD.

Methods: MAP COPD (goal n=200) is a partnership between the COPD Foundation and the University of Michigan to establish an early COPD cohort. SOURCE (goal n=650) is an NHLBI-funded early COPD cohort recruiting across 12 US centers in the SPIROMICS network. Enrollment criteria for both studies include age 30-55 years and smoking history ?10 pack years. All participants undergo baseline spirometry, high resolution CT (HRCT) of the chest, blood biomarker analysis and symptom assessment using the Chronic Airways Assessment Test (CAAT), a modification of the COPD Assessment Test.

Results: We report initial results from 109 MAP COPD and 70 co-enrolled SOURCE participants at the University of Michigan. Mean age was 47.3 years, 53.2% of participants were female and 57.8% were currently smoking. Mean CAAT score was high in all spirometry groups: 11.4 in GOLD 0 (n=87), 12.5 in PRISm (n=8), 11.0 in GOLD 1 (n=2) and 15.8 in GOLD 2 (n=12). For alpha-1 antitrypsin, 7.8% of participants had a phenotype other than MM. On visual inspection of HRCTs, 39.8% had emphysema (39.5% of GOLD 0, 25.0% of PRISm; most with a centrilobular pattern), 39.8% one or more non-calcified lung nodules, 11.1% gas trapping and 9.3% respiratory bronchiolitis.

Conclusion: High respiratory symptom burden and evidence of emphysema on CT were prevalent in individuals with a smoking history and early COPD, including those without spirometric airflow obstruction.