In the salmeterol group , patients with Arg@Arg genotype had a significantly reduced exacerbation risk compared with patients with Arg@Gly ( p = @ ) and Gly@Gly ( p = @ ) genotypes ( proportion of patients with at least one exacerbation was @ % in Arg@Arg , @ % in Arg@Gly , and @ % in Gly@Gly ) .