Publications by authors named "Lindsey R Hammerslag"

Importance: Controlled substances have regulatory requirements under the US Federal Controlled Substance Act that must be met before pharmacies can stock and dispense them. However, emerging evidence suggests there are pharmacy-level barriers in access to buprenorphine for treatment for opioid use disorder even among pharmacies that dispense other opioids.

Objective: To estimate the proportion of Medicaid-participating community retail pharmacies that dispense buprenorphine, out of Medicaid-participating community retail pharmacies that dispense other opioids and assess if the proportion dispensing buprenorphine varies by Medicaid patient volume or rural-urban location.

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Introduction: Long-acting injectable buprenorphine (LAI-bup) formulations have advantages over transmucosal buprenorphine (TM-bup), but barriers may limit their utilization. Several policies shifted during the COVID-19 pandemic to promote buprenorphine access. The federal government expanded telemedicine treatment for opioid use disorder and Kentucky (KY) Medicaid lifted prior authorization requirements (PAs) for LAI-bup (i.

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Objective: To describe the process of establishing a Methadone Central Registry (MCR) as part of the HEALing (Helping to End Addiction Long-term) Communities Study (HCS) and to support recommendations with evidence of its functionality relative to Medicaid claims data for monitoring utilization of methadone, an evidence-based treatment for opioid use disorder.

Design And Participants: The manuscript authors were active participants in establishing the MCR and include representation from state government, Opioid Treatment Programs (OTPs), and HCS university partners. Secondary data were obtained from Kentucky's (KY's) MCR and Medicaid claims from July 2020 through June 2021.

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Article Synopsis
  • The study focuses on how COVID-19 telemedicine strategies impacted treatment for opioid use disorder (OUD) through transmucosal buprenorphine, comparing telemedicine to traditional in-person methods.
  • By analyzing Medicaid data from Kentucky and Ohio between November 2019 and December 2020, the research aims to assess treatment retention and nonfatal opioid overdoses tied to the method of treatment initiation.
  • Results involve over 41,000 individuals in Kentucky and 50,000 in Ohio, highlighting the demographic composition and the significance of telemedicine in maintaining OUD treatment during the pandemic.
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Importance: Federal and state agencies granted temporary regulatory waivers to prevent disruptions in access to medication for opioid use disorder (MOUD) during the COVID-19 pandemic, including expanding access to telehealth for MOUD. Little is known about changes in MOUD receipt and initiation among Medicaid enrollees during the pandemic.

Objectives: To examine changes in receipt of any MOUD, initiation of MOUD (in-person vs telehealth), and the proportion of days covered (PDC) with MOUD after initiation from before to after declaration of the COVID-19 public health emergency (PHE).

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Background: Congenital syphilis can cause severe morbidity, including miscarriage and stillbirth, and rates are increasing rapidly within the United States. However, congenital syphilis can be prevented with early detection and treatment of syphilis during pregnancy. Current screening recommendations propose that all women should be screened early in pregnancy, whereas women with elevated risks for congenital syphilis should be screened again later in pregnancy.

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The purpose of this study was to determine if social vs nonsocial cues (peer vs light/tone) can serve as discriminative stimuli to reinstate cocaine seeking. In addition, to assess a potential mechanism, an oxytocin (OT) promoter-linked hM3Dq DREADD was infused into the paraventricular nucleus of the hypothalamus to determine whether peer-induced cocaine seeking is decreased by activation of OT neurons. Male rats underwent twice-daily self-administration sessions, once with cocaine in the presence of one peer (S+) and once with saline in the presence of a different peer (S-).

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Rationale: Opioid use disorder (OUD) is highly comorbid with stress-related disorders, and stress can serve as a trigger for reinstatement of drug seeking. Glucocorticoid receptor (GR) antagonists such as mifepristone (RU-486) may be effective against stress-induced drug seeking. In the current study, PT150 (formerly ORG-34517), a more selective GR antagonist, was tested using two models of stress-induced drug seeking, namely footshock and yohimbine.

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Rationale: Escalation of drug intake and craving are two DSM-5 hallmark symptoms of opioid use disorder (OUD).

Objectives: This study determined if escalation of intake as modeled by long access (LgA) self-administration (SA) and craving measured by reinstatement are related.

Methods: Adult male and female Sprague-Dawley rats were trained to self-administer fentanyl across 7 daily 1-h short access (ShA) sessions, followed by 21 SA sessions of either 1- or 6-h duration (ShA or LgA).

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Early life adversity can set the trajectory for later psychiatric disorders, including substance use disorders. There are a host of neurobiological factors that may play a role in the negative trajectory. The current review examines preclinical evidence suggesting that early life adversity specifically involving social factors (maternal separation, adolescent social isolation and adolescent social defeat) may influence drug abuse vulnerability by strengthening corticotropin-releasing factor (CRF) systems and weakening oxytocin (OT) systems.

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Background: Individuals with opioid use disorder (OUD) exhibit high levels of economic demand for opioids, with high levels of consumption and relative insensitivity to changes in price. Because the medications used to treat OUD in medication-assisted therapy (MAT) act as antagonists or agonists at μ opioid receptors, they may alter the relationship between price and opioid intake.

Methods: This study examined demand for a commonly abused synthetic prescription opioid, fentanyl, in male rats following s.

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Adolescence is a period associated with increased risk taking and peer relations. Research has shown that age is correlated with vulnerability to peer pressure, with youth being more influenced by peers compared with adults, leading to exacerbated risk taking, including risk for drug abuse. Preclinical research suggests that these findings may also be applicable to rodents, as younger rats find social interaction rewarding and are prone to risky behavior.

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Background: An important factor that can lead to drug relapse is to re-associate with drug-using social peers, but there is little literature on the effect of social peers on relapse in animal models.

Methods: The current study used a dual-compartment operant conditioning apparatus that allowed adult male rats to respond for cocaine in the presence of a conspecific. In experiment 1, rats were trained to self-administer cocaine in the presence of a social peer that was separated by a wire screen partition and then that peer was used as a reinstatement cue following a period of extinction.

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Impulsivity is a personality trait associated with a heightened risk for drug use and other psychiatric conditions. Because impulsivity-related disorders typically emerge during adolescence, there has been interest in exploring methods for identifying adolescents that will be at risk to develop substance use disorders in adulthood. Here, we used a rodent model to assess inhibitory control (impulsive action) and impulsive decision making (impulsive choice) during adolescence (43-50 days old) or adulthood (93-100 days old) and then examined the impact of development on these impulsivity traits by re-testing rats 50 days later.

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Objectives: Normal aging results in cognitive decline and nutritional interventions have been suggested as potential approaches for mitigating these deficits. Here, we used rats to investigate the effects of short- and long-term dietary supplementation with the leucine metabolite β-hydroxy-β-methyl butyrate (HMB) on working memory and cognitive flexibility.

Methods: Beginning ∼12 months of age, male and female Long-Evans rats were given twice daily access to sipper tubes containing calcium HMB (450 mg/kg) or vehicle (285 mg/kg calcium lactate) in a sucrose solution (20% w/v).

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Adolescents are especially prone to risky behavior and to the emergence of psychological disorders like substance abuse, anxiety and depression. However, there is a sex (or gender) difference in this vulnerability, with females being more prone to developing internalizing disorders and males being more likely to engage in risky behavior and drug use. While several researchers have proposed that there is a relationship between corticolimbic circuit development and adolescent vulnerability, the current proposed models do not take sex differences into account.

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Heightened impulsivity is a feature of some psychiatric disorders, including addiction, that also have sex-specific patterns of expression. The relationship between addiction and impulsivity may be driven by drug-induced changes in behavior caused by long term adaptations in signaling within the medial prefrontal cortex (mPFC). Here, we used a response inhibition task that is sensitive to changes in mPFC function to examine the effects of sex and exposure to amphetamine (AMPH) on impulsive action and vigilance.

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WC 44 and WC 10 are phenylpiperazines with low (23 fold) to moderate (42 fold) selectivity for dopamine D3 receptors (D3Rs) over D2Rs, respectively. WC 44 is a full D3R agonist in the forskolin-stimulated adenylyl cyclase (AC) assay, whereas WC 10 has little efficacy. In contrast to their opposite effects in the AC assay, these drugs often produce similar behavioral effects, suggesting that the AC assay does not predict the efficacy of these drugs in vivo.

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Compared to adults, adolescents are at heightened risk for drug abuse and dependence. One of the factors contributing to this vulnerability may be age-dependent differences in reward processing, with adolescents approaching reward through stimulus-directed, rather than goal-directed, processes. However, the empirical evidence for this in rodent models of adolescence, particularly those that investigate both sexes, is limited.

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