Association Between Exposure to Complementary and Integrative Therapies and Opioid Analgesic Daily Dose Among Patients on Long-term Opioid Therapy

Objectives: To describe the association between exposure to selected complementary and integrative health (CIH) modalities and the trajectory of prescribed opioid analgesic dose within a national cohort of patients receiving long-term opioid therapy (LTOT) in the Veterans Health Administration (VHA).

Materials and methods: Using national data from VHA electronic health records between October 1, 2017 and September 30, 2019, CIH use was analyzed among 57,437 patients receiving LTOT within 18 VHA facilities serving as evaluation sites of VHA's Whole Health System of Care. Using linear mixed effects modeling controlling for covariates, opioid dose was modeled as a function of time, CIH exposure, and their interaction.

Results: Overall, 11.91% of patients on LTOT used any of the focus CIH therapies; 43.25% of those had 4 or more encounters. Patients used acupuncture, chiropractic care, and meditation modalities primarily. CIH use was associated with being female, Black, having a mental health diagnosis, obesity, pain intensity, and baseline morphine-equivalent daily dose. Mean baseline morphine-equivalent daily dose was 40.81 milligrams and dose decreased on average over time. Controlling for covariates, patients with any CIH exposure experienced 38% faster dose tapering, corresponding to a mean difference in 12-month reduction over patients not engaging in CIH of 2.88 milligrams or 7.06% of the mean starting dose.

Discussion: Results support the role of CIH modalities in opioid tapering. The study design precludes inference about the causal effects of CIH on tapering. Analyses did not consider the trend in opioid dose before cohort entry nor the use of other nonopioid treatments for pain. Future research should address these questions and consider tapering-associated adverse events.