IMPACT OF UMECLIDINIUM/VILANTEROL (UMEC/VI) VS TIOTROPIUM (TIO), FLUTICASONE PROPIONATE/SALMETEROL (FP/SAL), AND BUDESONIDE/FORMOTEROL (B/F) ON TIME-TO-FIRST SEVERE EXACERBATION AMONG PATIENTS WITH COPD WITH HIGH COMORBIDITIES AND HIGH COSTS