Relationship of pain and ancestry in African American women

BackgroundAfrican Americans are reported to be more sensitive to pain than European Americans. Pain sensitivity has been shown to be genetically linked in animal models and is likely to be in humans. MethodsExactly, 11,239 self-identified African American post-menopausal women enrolled in the Women's Health Initiative had percentage African ancestry determined by ancestry informative markers, Pain Construct measurements and covariate information. They answered five questions about specific types and location of pain, such as joint, neck, low back, headache and urinary. They also answered two questions which were used to derive a Pain Construct, a measure of general pain scored on a scale of 1-100. Associations were tested in linear regression models adjusting for age, self-reported medical conditions, neighbourhood socio-economic status, education and depression. ResultsIn the unadjusted model of the five specific types of pain measures, greater pain perception was associated with a higher proportion of African ancestry. However, some of the specific types of pain measures were no longer associated with African ancestry after adjustment for other study covariates. The Pain Construct was statistically significantly associated with African ancestry in both the unadjusted [=-0.132, 95% confidence interval (CI)=-099 to -0.164; r=-0.075, 95% CI -0.056 to -0.093] and the adjusted models (=-0.069 95% CI=-0.04 to -0.10). ConclusionsGreater African ancestry was associated with higher levels of self-reported pain, although this accounted for only a minor fraction of the overall variation in the Pain Construct.