Lower serum IgA is associated with COPD exacerbation risk in SPIROMICS.

Putcha N, Paul GG, Azar A, Wise RA, O'Neal WK, Dransfield MT, Woodruff PG, Curtis JL, Comellas AP, Drummond MB, Lambert AA, Paulin LM, Fawzy A, Kanner RE, Paine R, Han MK, Martinez FJ, Bowler RP, Barr RG, Hansel NN