Circadian rhythmicity and biopsychosocial characteristics influence  opioid use in chronic low back pain
Inter- and intra-individual fluctuations in pain intensity pose a major challenge to treatment efficacy, with a majority perceiving their pain relief as inadequate. Recent preclinical studies have identified circadian rhythmicity as a potential contributor to these fluctuations and therapeutic target. We therefore sought to determine the impact of these rhythms in people with chronic low back pain (CLBP) through a detailed characterization, including questionnaires to evaluate biopsychosocial characteristics, ecological momentary assessment (7-day e-diaries at 8:00/14:00/20:00) to assess pain fluctuations, and intra-day blood transcriptomics (8:00/20:00) to identify genes/pathways of interest. Human peripheral blood samples were collected during the day (7:00-9:00) and night (19:00-21:00) from participants with chronic low back pain.