Arg16Gly ADRB2 alleles were not associated with differences in the effects of tiotropium + ICS vs LABA+ICS ( hazard ratio for time to first exacerbation , 0.84 [ 95 % CI , 0.47 to 1.51 ] for Arg/Arg vs 0.85 [ 95 % CI , 0.63 to 1.15 ] for Arg/Gly or Gly/Gly , P = .97 ) .