SERPINE1 and infection: When we looked at the joint effect of PAI-1 genotype-and early life infections, FEV1% predicted, and FEV1/FVC % predicted were further reduced in AG/AA+LRI group compared to GG no LRI group (P = 0.03, coefficient β -2.06 95% CI -3.97–-0.16; and P = 0.001, coefficient β -1.97 95% CI -3.10–-0.84, respectively).