Relationship between post-traumatic stress disorder and pain in two American Indian tribes

Objectives. To estimate the association of lifetime post-traumatic stress disorder (PTSD) and pain in American Indians, and determine if tribe, sex, cultural and psychosocial factors, or major depression influence the magnitude of this association. Design. A cross-sectional probability sample survey completed between 1997 and 2000. A structured interview was conducted by trained, tribal members to gather information on demographic and cultural features, physical health status, psychiatric disorders, and functional status. Setting. General community. Participants. A total of 3,084 individuals randomly selected from the tribal rolls of a Southwestern (N = 1,446) and a Northern Plains (N = 1,638) tribal group who were 15-54 years of age and lived on or within 20 miles of their reservations. Outcome measures. Bodily pain subscale of the Short Form-36. Linear regression models were fit to examine the association between lifetime PTSD and pain, adjusting for demographic, cultural, psychosocial features, painful medical conditions, and major depression. Results. The prevalence of lifetime PTSD was 16% in the Southwestern and 14% in the Northern Plains; women were nearly twice as likely as men to have lifetime PTSD in both tribes. The final adjusted model demonstrated that mean Short Form-36 bodily pain subscale scores were lower (indicating more pain) among individuals with lifetime PTSD than those without lifetime PTSD. Effect modification by tribe, sex, and depression was not observed. Conclusions. Lifetime PTSD was strongly associated with bodily pain in this rural sample of American Indians. Clinicians should be aware of, and address, the link between physical pain syndromes and PTSD.