Access challenges to opioid use disorder treatment among individuals experiencing homelessness: Voices from the streets

BACKGROUND

Achieving equitable access to medications for opioid use disorder (MOUD) such as buprenorphine is a pressing issue. Evidence suggests disparities in MOUD access based on race and socioeconomic status, further exacerbated by the COVID-19 pandemic. However, the drivers behind this access gap remain poorly understood. This study explores barriers to treatment access among individuals with opioid use disorder (OUD) experiencing homelessness.

METHODS

We interviewed 28 individuals in and around the Boston Public Health Commission (BPHC) Engagement Center, an area known for its high density of active substance use and homelessness. We asked about people's experiences, perceptions, and attitudes toward OUD treatment. We conducted a thematic analysis of our interview data.

RESULTS

Fifty-four percent of participants sampled were not prescribed MOUD. None of the participants reported having an active prescription of sublingual buprenorphine or buprenorphine/naloxone. White participants were more likely to have been prescribed buprenorphine in the past compared to participants of other races even in this socioeconomically homogeneous sample. Themes that emerged in our data included challenges to accessing MOUD due to reduced services during the COVID-19 pandemic, lost or stolen medications, fewer inpatient withdrawal management beds for women, transportation challenges, fear of adverse effects of MOUD, the perception that taking MOUD replaces one addiction for another, and community disapproval of MOUD. Participants also reported stigma and discrimination based on race, gender, and socioeconomic status.

CONCLUSION

Systems and individual-level factors contribute to the MOUD treatment gap across race and socioeconomic status. The COVID-19 pandemic posed additional access challenges. This study provides important, actionable insights about the barriers faced by a particularly vulnerable population of individuals with OUD experiencing homelessness.

Visualization of Tau⁻Tubulin Interaction in a Living Cell Using Bifluorescence Complementation Technique

Tau is a neuron-specific microtubule-binding protein that stabilizes microtubules. It is generally thought that highly phosphorylated tau dissociates from microtubules and becomes insoluble aggregates, leading to neuronal degeneration. Due to the implication of tau aggregation in neurodegenerative disorders, including Alzheimer’s disease, great efforts have been made to identify the tau aggregation process. However, tau interaction with tubulin during the aggregation process remains largely unknown. To scrutinize the tau-tubulin interaction, we generated a cell model that enables visualization of the tau-tubulin interaction in a living cell using the Bifluorescence Complementation (BiFC) Technique. Upon diverse chemical stimulation that induced tau pathology, tau-tubulin BiFC cells showed significantly increased levels of BiFC fluorescence, indicating that tau aggregates together with tubulin. Our results suggest that tubulin should be considered as a key component in the tau aggregation process.

Effects of subcortical cerebral infarction on cortical glucose metabolism and cognitive function

BACKGROUND

The mechanism of dementia in subcortical cerebral infarction is incompletely understood.

OBJECTIVE

To determine how cognitive function is related to cortical metabolism in patients with subcortical infarction and a continuum of cognitive impairment.

METHODS

We used positron emission tomography (PET) and the glucose metabolic tracer fludeoxyglucose F 18 to study 8 patients with subcortical stroke and normal cognitive function (S-CN), 5 patients with subcortical stroke and cognitive impairment (S-CI) who did not have dementia, 8 patients with subcortical stroke and dementia (S-D), and 11 controls with no cognitive impairment or stroke. A subset of patients had absolute regional cerebral metabolic rate of glucose (CMRglc) determined, while in all subjects regional tracer uptake normalized to whole brain tracer uptake was calculated. PET data were analyzed by constructing volumes of interest using coregistered magnetic resonance imaging data and correcting the PET data for atrophy.

RESULTS

Global CMRglc was significantly lower in the patients with S-D than in the control and S-CN groups, with S-CI rates intermediate to those of the S-D and S-CN groups. Absolute regional CMRs of glucose were similar in the S-D and S-CI groups and in the control and S-CN groups. The regional pattern, however, showed lower right frontal regional CMRglc ratios in all stroke groups compared with the controls. There were modest correlations between performance on the Mini-Mental State Examination and whole brain CMRglc when all 4 groups were included.

CONCLUSIONS

These results demonstrate that subcortical infarction produces global cerebral hypometabolism, which is related to the clinical status of the patients. In addition, specific frontal lobe hypometabolism also appears to be a feature of subcortical infarction. Taken together, both global and regional effects on cortical function mediate the production of clinical symptoms in patients with subcortical strokes.