Human Studies

Previous studies suggest higher mindfulness may be associated with better sleep quality in people with chronic pain conditions. However, the relationship between mindfulness and sleep in fibromyalgia patients, who commonly suffer from sleep problems, remains unstudied. We examined the relationship between mindfulness and sleep, and how this relationship may be mediated by depression, anxiety, and pain interference in fibromyalgia patients.

Drawing on advances in chronic pain metrics, a simplified Graded Chronic Pain Scale Revised (GCPS-R) was developed to differentiate mild, bothersome and high impact chronic pain. GCPS-R was validated among adult enrollees of two health plans (N=2021). In this population, the prevalence of chronic pain (pain present most or every day, prior 3 months) was 40.5%: 15.4% with mild chronic pain (lower pain intensity and interference); 10.1% bothersome chronic pain (moderate to severe pain intensity with lower life activities interference); and 15.0% high impact chronic pain (sustained pain-related activity limitations). Persons with mild chronic pain versus those without chronic pain showed small differences on ten health status indicators (unfavorable health perceptions, activity limitations, receiving long-term opioid therapy), with non-significant differences for 7 of 10 indicators. Persons with bothersome versus mild chronic pain differed significantly on 6 of 10 indicators (e.g., negative pain coping beliefs, psychological distress, unfavorable health perceptions and pain-related interference with overall activities). Persons with high impact chronic pain differed significantly from those with mild chronic pain on all 10 indicators. Persons with high impact chronic pain, relative to those with bothersome chronic pain, were more likely to have substantial activity limitations (significant differences for 4 of 5 disability indicators) and more often received long-term opioid therapy. GCPS-R strongly predicted five activity limitation indicators with area under receiver operating characteristic curve coefficients of 0.76 to 0.89. We conclude that the 5 item GCPS-R and its scoring rules provide a brief, simple and valid method for assessing chronic pain.

Approximately 1.7 million youth suffer from debilitating chronic pain in the US alone, conferring risk for continued pain in adulthood. Abberations in threat-safety (T-S) discrimination are proposed to contribute to pain chronicity in adults and youth by interacting with pain-related distress. Yet, few studies have examined the neural circuitry underlying T-S discrimination in patients with chronic pain or how T-S discrimination relates to pain-related distress. In this study, 91 adolescents (10-24 years; 78 females) including 30 chronic pain patients with high pain-related distress, 29 chronic pain patients with low pain-related distress, and 32 healthy peers without chronic pain completed a developmentally-appropriate T-S learning paradigm. We measured self-reported fear, psychophysiology (skin conductance response), and functional MRI responses (N = 72 after fMRI exclusions). After controlling for age and anxiety symptoms, patients with high pain-related distress showed altered self-reported fear and fronto-limbic activity in response to learned threat and safety cues compared to both patients with low pain-related distress and healthy controls. Specifically, adolescent patients with high pain-related distress reported elevated fear and showed elevated limbic (hippocampus, amygdala) activation in response to a learned threat cue (CS+). In addition, they showed decreased frontal (vmPFC) activation and aberrant fronto-limbic connectivity in response to a learned safety cue (CS-). Patients with low pain-related distress and healthy controls appeared strikingly similar across brain and behavior. These findings indicate that altered T-S discrimination, mediated by fronto-limbic activation and connectivity, may be one mechanism maintaining pain chronicity in adolescents with high levels of pain-related distress.