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Outcomes of prescription opioid dose escalation for chronic pain: results from a prospective cohort study.

The use of long-term opioid therapy for chronic pain remains common, yet data on long-term outcomes, especially after dose escalation, are sparse. This study examined potential benefits and harms associated with prescription opioid dose escalation. Participants from two institutions were enrolled in a two-year prospective cohort study. All participants (n=517) had a musculoskeletal pain diagnosis and were receiving a stable dose of long-term opioid therapy at baseline. Participants completed self-report measures of pain, disability, depression, and potential adverse effects at baseline and every six months for two years. We reviewed electronic health record data weekly to identify episodes of prescription opioid dose escalation; participants who had increases in their dose were seen for additional research visits within one month of dose escalation. Over two years, 19.5% of participants had prescription opioid dose increases. After controlling for covariates, there were no significant changes on any variable following dose escalation. Of those with a dose increase, 3% experienced a clinically meaningful improvement in pain following dose escalation. Participants in the entire sample had small improvements in pain intensity, depressive symptoms, medication-related side effects, and lower risk for prescription opioid misuse during the study period. Sexual functioning worsened over time. There were no significant changes in the full sample on pain disability, sleep functioning, or experiencing a fall. In summary, patients prescribed stable doses of long-term opioid therapy may demonstrate small changes in key pain-related outcomes over time, but prescription opioid dose escalation status is unrelated to clinical outcomes.

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Transition from Acute to Chronic Pain in Lower Extremity Fracture Patients: A Pain Phenotyping Protocol.

Traumatic injury is a major source of chronic pain, particularly for individuals with traumatic fracture of the fibula and/or tibia (lower extremity fracture) [LEFx]. Although several factors (e.g., older age, being female sex, high pain intensity at time of initial injury) have been identified as risk factors for chronic pain associated with LEFx. Comprehensive biopsychosical models to predict the odds of transitioning from acute to chronic pain after LEFx are needed to better understand the underlying processes, predict risk for chronic pain, and develop personalized therapies for individuals at higher risk for developing chronic pain.

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An fMRI-based neural marker for migraine without aura.

To identify and validate an fMRI-based neural marker for migraine without aura (MwoA) and to examine its association with treatment response.

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Effects of Lasmiditan on Cardiovascular Parameters and Pharmacokinetics in Healthy Subjects Receiving Oral Doses of Propranolol.

Lasmiditan (LY573144/COL-144) is a high-affinity, centrally penetrant, selective 5-HT receptor agonist currently under investigation for acute treatment of migraine. Although lasmiditan is not known to induce vasoconstriction, it remains important to understand its effect on cardiovascular parameters because it is likely to be coadministered with β-adrenergic receptor antagonists used for migraine prophylaxis, such as propranolol. This phase 1, single-center, open-label, fixed-sequence study evaluated the cardiovascular and pharmacokinetic effects of 200 mg lasmiditan in 44 healthy subjects receiving repeated oral doses of twice-daily 80 mg propranolol under fasting conditions. Coadministration caused statistically significant decreases in mean hourly heart rate relative to propranolol alone, but the maximum magnitude of this effect was -6.5 bpm and recovered to predose levels by 3 to 4 hours before stabilizing. Additionally, short-lived (≤2.5 hours) statistically significant increases in systolic blood pressure (8.3 mm Hg) and diastolic blood pressure (6.4 mm Hg) were observed following coadministration. Consistent with the largely nonoverlapping metabolic pathways of lasmiditan and propranolol, exposure to either drug was not affected by coadministration. Overall, compared with administration of either drug alone, coadministration was generally well tolerated.

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Further Examination of the Pain Stages of Change Questionnaires Among Chronic Low Back Pain Patients: Long-Term Predictive Validity of Pre- and Post-Treatment Change Scores and Stability of Post-Treatment Scores.

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Offset analgesia and onset hyperalgesia with different stimulus ranges.

Offset analgesia (OA), a large reduction in pain after a brief increase in intensity of an otherwise stable painful stimulus, has been established by a large body of research. But the opposite effect, onset hyperalgesia (OH), a disproportional hyperalgesic response after a briefly decreased intensity of a painful stimulus, has only been investigated in one previous study.

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Altruistic behaviors relieve physical pain.

Engaging in altruistic behaviors is costly, but it contributes to the health and well-being of the performer of such behaviors. The present research offers a take on how this paradox can be understood. Across 2 pilot studies and 3 experiments, we showed a pain-relieving effect of performing altruistic behaviors. Acting altruistically relieved not only acutely induced physical pain among healthy adults but also chronic pain among cancer patients. Using functional MRI, we found that after individuals performed altruistic actions brain activity in the dorsal anterior cingulate cortex and bilateral insula in response to a painful shock was significantly reduced. This reduced pain-induced activation in the right insula was mediated by the neural activity in the ventral medial prefrontal cortex (VMPFC), while the activation of the VMPFC was positively correlated with the performer's experienced meaningfulness from his or her altruistic behavior. Our findings suggest that incurring personal costs to help others may buffer the performers from unpleasant conditions.

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Effects of Acute Experimental Stress on Pain Sensitivity and Cortisol Levels in Healthy Participants: A Randomized Crossover Pilot Study.

To investigate pain sensitivity in the masseter muscle and index finger in response to acute psychologic stress in healthy participants.

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Naltrexone during pain conditioning: A double-blind placebo-controlled experimental trial.

Naltrexone reversibly blocks the effects of opioids and has been shown to decrease placebo analgesia. However, it is not clear (1) to what extent naltrexone affects pain modulation in a nontreatment context, for example, in response to pain cues or (2) how naltrexone given prior to pain-cue learning shapes pain responses. In a double-blind procedure prior to pain-cue conditioning, 30 healthy participants were randomized to receive an oral dose of naltrexone (50 mg) or inert pill. During functional magnetic resonance imaging, high and low pain pressures were paired with two different visual cues: a high pain cue and a low pain cue (learning sequence). During a test sequence, medium levels of pressure were used for both cues and the difference in subjective pain ratings following high and low pain cues was calculated. Results showed significant conditioned pain responses across groups (<.001); however, no significant difference between participants receiving naltrexone or inert pill (=.193). There was a significant correlation between the difference in high and low pain ratings during the learning sequence and the effect of high and low pain cues during the test sequence (r = .575, =.002). Functional magnetic resonance imaging analyses revealed no significant difference in brain activation between groups. Here, we demonstrate comparable learning of pain responses in participants treated with naltrexone or inert pill. The results point to the possibility that associative learning, and conditional responding to pain cues, is not dependent on endogenous opioids. Our results, using pain-cue conditioning to create reduced pain responses, contrast previous studies where opioid antagonists significantly reduced the placebo effect in treatment of pain.

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Somatosensory Profiling of Patients with Burning Mouth Syndrome and Correlations with Psychologic Factors.

To compare somatosensory function profiles and psychologic factors in patients with primary burning mouth syndrome (BMS) and healthy controls and to evaluate correlations of subjective pain ratings with somatosensory and psychologic parameters.

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