Negative affect and emotion dysregulation among people who inject drugs: An ecological momentary assessment study
This study used ecological momentary assessment (EMA) to measure positive and negative affect among people who inject drugs (PWID), and examined associations with borderline personality disorder (BPD) symptoms and difficulties with emotion regulation, in the context of injection drug use. We recruited PWID, age 18-35, through syringe exchange program sites in Chicago, Illinois, USA. After completing a baseline interview including a screener for BPD and the Difficulties with Emotion Regulation Scale (DERS), participants used a mobile phone app to report mood, substance use, and injection behavior for two weeks. Participants who completed at least two EMA assessments were included in the analysis (N = 161). The mean age was 30, about one-third were women, 63% were non-Hispanic white, and 23% were Hispanic. In multivariable mixed effects regression models, positive BPD screen was associated with greater momentary negative affect (NA) intensity, and greater instability of both NA and positive affect (PA). Independent of BPD screening status, DERS score was associated positively with momentary NA intensity and instability, and negatively with positive affect (PA) intensity. This finding suggests that emotion dysregulation is an appropriate target for assessment and intervention. While concurrent withdrawal was associated with both greater NA and less PA, opioid intoxication was associated only with greater PA. We did not find support for our hypothesis that emotion dysregulation would moderate the effect of withdrawal on NA. Findings support the validity of the EMA mood measure and the utility of studying mood and behavior among PWID using EMA on mobile phones.