Psychological and Genetic Predictors of Pain Sensitivity

Abstract

Specific Aims: To assess influence of PCS and FPQ-III on pain tolerance as well as SNPs TRPA1(rs11988795), COMT (rs4646312, rs6269) and FAAH(rs 932816, rs4141964, rs2295633). Methods: A Pain Catastrophizing Scale (PCS) and Fear of Pain Questionnaire (FPQ-III) were completed by a total of 89 healthy adults. A genetic analysis from cheek swabs was performed for single nucleotide polymorphisms(SNPs) within genes: TRPA1, COMT, and FAAH. A cold-pressor test involving the non-dominant hand inserted in circulating water kept at 1-3 degrees Celsius was used and the duration of time subjects were able to leave their hand in the water (pain tolerance) was measured as the primary outcome. Linear regression analysis was used to identify predictors of pain tolerance. Main Results: The subjects were 58% female, the majority were Caucasian (51%) with 26% Asian, 14% Hispanic and 9% other. The mean pain tolerance was 121 ± 66 seconds and regression analysis showed female sex (p=0.001), Asian race (p=0.001), PCS score (<0.001) and FPQ-III score (p=0.014) were associated with decreased pain tolerance while the SNPs were not. Conclusion: Psychological factors and patient demographics are associated with pain tolerance but the single nucleotide polymorphisms evaluated were not. Future pain studies should utilize a psychological assessment to adjust for this as a confounder.