male subjects (F 2,68 = 0.032, P = 0.969). Neither the main effect of gender nor the SNP×gender interaction was significant (data not shown). Significant associations were not observed between the two SNPs and NRS pain scores (G-1250A: F 2,94 = 1.455, P = 0.239; A1032G: F 2,96 = 0.115, P = 0.892), although significant positive correlations were found between NRS pain scores and frequency of rescue analgesic administration (r = 0.281, P = 0.004) and between NRS pain scores and total dose of rescue analgesics administered (r = 0.266, P = 0.006), indicating that the patients who received analgesics more frequently felt more pain, possibly attributable to insufficient analgesic effects.
