Native Americans (NA) experience higher rates of chronic pain than other U.S. racial/ethnic groups. Our research has indicated discrimination and stress play a role in chronic pain onset. However, chronic pain research has mostly relied on retrospective reports that may be impacted by recall bias. The current study was a secondary analysis of data from 208 NA, 206 Black, 202 Latinx, and 206 non-Hispanic White (NHW) participants from an efficacy trial of a mobile health intervention for depression and anxiety. Participants were prompted to complete 6 months of twice daily ecological momentary assessments (EMAs) that included stress and pain. Discrimination was assessed at baseline. Pain EMAs were used to reduce recall bias and estimate chronic pain prevalence. Dynamic structural equation modeling assessed the impact of race/ethnicity and discrimination on stress-pain relationships, as well as pain and stress dynamics. To assess chronic pain (pain ≥3-months), participants had to complete ≥3-months of consecutive EMAs, leaving 578 participants available for primary analyses (there were no racial/ethnic differences in EMA completion). Results showed NAs had the highest rate of chronic pain that was statistically significantly higher than NHW and Black participants. Controlling discrimination eliminated the NA-NHW, but not the NA-Black, pain inequity. Moreover, a reciprocal stress-pain relationship was found and was stronger in NAs than other groups. Discrimination did not exacerbate stress-pain relationships but was associated with higher rates of chronic pain and greater pain fluctuations, regardless of race/ethnicity. These findings indicate that targeting stress and discrimination could help reduce the NA pain inequity.

Native Americans experienced a self-reinforcing stress-pain cycle in which stress predicted future pain and pain predicted future stress. This cycle was stronger than Black, Latinx, and non-Hispanic White groups. Discrimination was associated with chronic pain but not stronger stress-pain relationships. These findings have implications for treatment.