Definition of adjustment variables
PAD
PAD, EVENTS, DIABETES MELLITUS
Adjustment was performed in two a priori defined adjustment steps. Model 1 with adjustment for the variables age, sex, and one or more air pollutants formed the first step and is referred to as "basic adjustment" in the further course. Model 2 was labeled as "full adjustment" and additionally included the education status (International standard classification of eduction (ISCED)), smoking status, pack-years, body-mass-index, estimated glomerular filtration rate (eGFR), C-reactive protein (CRP), vitamin D, homocysteine, low-density lipoprotein (LDL), gamma-glutamyltransferase (GGT), arterial hypertension, diabetes mellitus, PAD, cardiovascular events prior to baseline, and intake of lipid-lowering, anticoagulant, antiplatelet, or digitalis medication.In order to investigate a possible effect of drug therapy on the impact of PM10 exposure, the intake of different drug groups was included in the analysis. Statins or fibrates were labeled as lipid-lowering medication. Anticoagulant medication was defined as the use of coumarin derivatives or heparin. Therapeutic use of acetylsalicylic acid, ticlopidine, clopidogrel, or dipyramidol was grouped under antiplatelet medication. The intake of digitalis was considered as a separate variable.The following seven interactions were pre-specified: each single air pollutant with PAD at baseline, NO