P values OR Age 0.01 1.05(1.01-1.10) Gender (male) 0.01 5.8 (1.3-25.2) Smokingpack/year 0.06 1.02(0.9-1.05)  Income 0.2 1.5(0.7-3.3) Education 0.6 0.9(0.6-1.39 Depression 0.1 1.5 (0.9-1.1)

Table 5: The Predictors of Presence of Airway Obstruction (FEV1/ FVC<70%).