The Perceived Role of Withdrawal in Maintaining Opioid Addiction among Adults with Untreated Opioid Use Disorder: A Survey of Syringe Exchange Program Participants.

Background: Withdrawal is believed to play a central role in the brain disease model of addiction. However, little research describes withdrawal-motives among untreated individuals in community settings. Methods: This cross-sectional study surveyed syringe exchange program participants (n = 139) with untreated opioid use disorder (OUD) in Columbus, Ohio from January 10th to March 25th, 2023, to assess their perceptions of the role of withdrawal in OUD maintenance, treatment delay, and OUD's refractoriness to buprenorphine. Participants responded to a survey including DSM-5 OUD criteria, demographics, and questions about substance use and opioid withdrawal. Participant ages ranged from 21 to 65 years with a mean age of 37.5 years and standard deviation of 8.1. The racial distribution of the sample was as follows: 81% White/Caucasian, 12% Black/African American, 3% Native American or Alaskan Native. Results: Sixty-six percent of participants agreed, or strongly agreed that opioid withdrawal was "the most important reason" they had been unable to stop using opioids. Almost seventy-one percent agreed, or strongly agreed that worry about opioid withdrawal had caused them to "put off or delay" OUD treatment. Although all participants had active, untreated OUD at the time of recruitment, most (85%) had previously tried buprenorphine, and the majority (78%) reported having experienced buprenorphine-precipitated withdrawal. Conclusions: Among this community sample of individuals with untreated OUD, withdrawal was perceived to have an important role in maintaining OUD, including by motivating OUD treatment delay. Prior buprenorphine-precipitated withdrawal was common, suggesting aversion to withdrawal might possibly be associated with OUD's refractoriness to buprenorphine.

Harnessing cortical plasticity via gabapentinoid administration promotes recovery after stroke.

Stroke causes devastating sensory-motor deficits and long-term disability due to disruption of descending motor pathways. Restoration of these functions enables independent living and therefore represents a high priority for those afflicted by stroke. Here, we report that daily administration of gabapentin, a clinically approved drug already used to treat various neurological disorders, promotes structural and functional plasticity of the corticospinal pathway after photothrombotic cortical stroke in adult mice. We found that gabapentin administration had no effects on vascular occlusion, haemodynamic changes nor survival of corticospinal neurons within the ipsilateral sensory-motor cortex in the acute stages of stroke. Instead, using a combination of tract tracing, electrical stimulation and functional connectivity mapping, we demonstrated that corticospinal axons originating from the contralateral side of the brain in mice administered gabapentin extend numerous collaterals, form new synaptic contacts and better integrate within spinal circuits that control forelimb muscles. Not only does gabapentin daily administration promote neuroplasticity, but it also dampens maladaptive plasticity by reducing the excitability of spinal motor circuitry. In turn, mice administered gabapentin starting 1 h or 1 day after stroke recovered skilled upper extremity function. Functional recovery persists even after stopping the treatment at 6 weeks following a stroke. Finally, chemogenetic silencing of cortical projections originating from the contralateral side of the brain transiently abrogated recovery in mice administered gabapentin, further supporting the conclusion that gabapentin-dependent reorganization of spared cortical pathways drives functional recovery after stroke. These observations highlight the strong potential for repurposing gabapentinoids as a promising treatment strategy for stroke repair.