Age of Onset and Its Related Factors in Cocaine or Methamphetamine Use in Adults from the United States: Results from NHANES 2005-2018

Predictors of abstinence maintenance after cocaine inpatient detoxification: A prospective study

BACKGROUND AND OBJECTIVES

Cocaine is a highly addictive substance, and with no approved medication for cocaine use disorder (CUD), leading to a heavy burden. Despite validated psychosocial treatments, relapse rates after detoxification are very high in CUD. Few consistent factors can predict abstinence after detoxification. Our study, therefore, aimed at identifying factors predicting abstinence among CUD patients after inpatient detoxification.

METHODS

Eighty-one CUD inpatients were included during detoxification and characterized for clinical and sociodemographic data at baseline and at a follow-up of 3 months after discharge, including a standard measure of their abstinence duration from cocaine. We performed Cox univariate analyzes to determine the factors associated with abstinence maintenance, followed by a multivariate Cox regression to identify independent predictors.

RESULTS

Abstinence maintenance was shorter in patients injecting cocaine (hazard ratio [HR] = 5.16, 95% confidence interval [CI]: 2.01-13.27, p < .001) and using cocaine heavily in the month before inclusion (HR = 1.03, 95% CI: 1.00-1.06, p = .046). Conversely, abstinence maintenance was longer in patients with longer inpatient detoxification stays (HR = 0.96, 95% CI: 0.94-0.99, p = .015) and prescribed with selective serotonin reuptake inhibitors (SSRIs) (HR = 0.30, 95% CI: 0.16-0.56, p < .001).

DISCUSSION AND CONCLUSIONS

Patients with severe CUD may require longer inpatient stays to achieve abstinence. Regarding SSRI prescription, more specific studies are needed to provide stronger recommendations about their use in clinical practice.

SCIENTIFIC SIGNIFICANCE

Our findings suggest several modifiable factors to improve inpatient treatment response in CUD. As there are no specific recommendations about the optimal duration of inpatient stay, our results could pave the way for evidence-based guidelines.

The gut microbiota contributes to methamphetamine-induced reproductive toxicity in male mice

Methamphetamine (METH) is a psychostimulant drug belonging to the amphetamine-type stimulant class, known to exert male reproductive toxicity. Recent studies suggest that METH can disrupt the gut microbiota. Furthermore, the gut-testis axis concept has gained attention due to the potential link between gut microbiome dysfunction and reproductive health. Nonetheless, the role of the gut microbiota in mediating the impact of METH on male reproductive toxicity remains unclear. In this study, we employed a mouse model exposed to escalating doses of METH to assess sperm quality, testicular pathology, and reproductive hormone levels. The fecal microbiota transplantation method was employed to investigate the effect of gut microbiota on male reproductive toxicity. Transcriptomic, metabolomic, and microbiological analyses were conducted to explore the damage mechanism to the male reproductive system caused by METH. We found that METH exposure led to hormonal disorders, decreased sperm quality, and changes in the gut microbiota and testicular metabolome in mice. Testicular RNA sequencing revealed enrichment of several Gene Ontology terms associated with reproductive processes, as well as PI3K-Akt signaling pathways. FMT conveyed similar reproductive damage from METH-treated mice to healthy recipient mice. The aforementioned findings suggest that the gut microbiota plays a substantial role in facilitating the reproductive toxicity caused by METH, thereby highlighting a prospective avenue for therapeutic intervention in the context of METH-induced infertility.

The ASAM/AAAP Clinical Practice Guideline on the Management of Stimulant Use Disorder

The American Society of Addiction Medicine/American Academy of Addiction Psychiatry (ASAM/AAAP) Clinical Practice Guideline on the Management of Stimulant Use Disorder provides guidance on evidence-based strategies for the treatment of stimulant use disorders (StUDs), stimulant intoxication, and stimulant withdrawal, as well as secondary and tertiary prevention of harms associated with stimulant use. The Clinical Guideline Committee (CGC) comprised experts from ASAM and AAAP representing a range of clinical settings and patient populations. The guideline was developed following modified GRADE methodology. The process included a systematic literature review as well as several targeted supplemental searches. The CGC utilized Evidence to Decision tables to review available evidence and rate the strength of each recommendation. The clinical practice guideline was revised based on external stakeholder review. Key takeaways included: Contingency management represents the current standard of care for treatment of StUDs; Pharmacotherapies may be utilized off-label to treat StUDs; Acute stimulant intoxication can result in life-threatening complications that should be addressed in an appropriate level of care; Secondary and tertiary prevention strategies should be used to reduce harms related to risky stimulant use.

Birth cohort-specific consideration in an Emergency Department Hepatitis C Testing Programme: A description of age-related characteristics and outcomes

The emergency department (ED) has increasingly become an important public health partner in non-targeted hepatitis C virus (HCV) testing and referral to care efforts. HCV has traditionally been an infection associated with the Baby Boomer generation; however, recent exacerbation of the opioid epidemic has resulted in a growing number of younger cohorts, namely Millennials, also impacted by HCV. Examination of this age-related demographic shift, including subsequent linkage success and linkage barriers, from the perspective of an ED-based testing and linkage programme may have implications for future population and health systems interventions. A retrospective descriptive chart review was performed, inclusive of data from August 2015 through December 2020. We compared the quantity of positive HCV screening antibody (Ab) and confirmatory (RNA) tests and further considered linkage rates and correlative demographics (e.g. gender, race). Patient barriers to HCV care linkage (e.g. substance misuse, lack of health insurance, homelessness) were also evaluated. The data set was disaggregated by birth cohort to include Silent Generation (SG) (1928-45), Baby Boomer (BB) (1946-64), Generation X (Gen X) (1965-80), Millennial (1981-96) and Generation Z (1997-2012). Descriptive statistics and chi-square analysis were performed. Overall, 83,817 patients were tested for HCV (50.6% of eligible); 6187 (7.4%) were HCV Ab positive, and 2665 were HCV RNA positive (3.2%). RNA-positive individuals were more likely to be white (70.4%) and male (67.7%); generational distribution was similar (BB 33.3%, Gen X 32.0% and Millennials 32.7%). Amongst Ab-positive patients, white (45.5%), male (47.2%) and Millennial (49.7%) individuals were most likely to be RNA-positive. Overall, 28.1% of the RNA-positive cohort successfully linked to care; linkage to care rates were significantly higher in older generations (38.1% in BB vs. 17.8% in Millennials) (p < .00001). Over 90% were identified as having at least one linkage to care barrier. Younger generations (Gen X and Millennials) were disproportionately impacted by linkage barriers, including incarceration, lack of health insurance, history of mental health and substance use disorders, as well as history of or active injection drug use (IDU) (p < .00001). Older generations (SG and BB) were more likely to be impacted by competing medical comorbidities (p < .00001). The ED population represents a particularly vulnerable, at-risk cohort with a high prevalence of HCV and linkage to care barriers. While past HCV-specific recommendations and interventions have focused on Baby Boomers, this data suggests that younger generations, including Gen X and Millennials, are increasingly affected by HCV and face disparate social risk and social need factors which impede definitive care linkage and treatment.

A systematic review and meta-analysis of health, functional, and cognitive outcomes in young people who use methamphetamine

Methamphetamine use typically starts in adolescence, and early onset is associated with worse outcomes. Yet, health, functional, and cognitive outcomes associated with methamphetamine use in young people are not well understood. The aim of this study was to comprehensively assess the evidence on health, functional, and cognitive outcomes in young people (10-25 years-old) who use methamphetamine. Sixty-six studies were included. The strongest association observed was with conduct disorder, with young people who use methamphetamine some 13 times more likely to meet conduct disorder criteria than controls. They were also more likely to have justice system involvement and to perpetrate violence against others. Educational problems were consistently associated with youth methamphetamine use. The cognitive domain most reliably implicated was inhibitory control. Key limitations in the literature were identified, including heterogenous measurement of exposure and outcomes, lack of adequate controls, and limited longitudinal evidence. Outcomes identified in the present review - suggesting complex and clinically significant behavioural issues in this population - are informative for the development of future research and targeted treatments.

Methamphetamine alters nucleus accumbens neural activation to monetary loss in healthy young adults

RATIONALE

Stimulant drugs like methamphetamine (MA) activate brain reward circuitry, which is linked to the development of problematic drug use. It is not clear how drugs like MA alter neural response to a non-drug reward.

OBJECTIVES

We examined how acute MA impacts neural response to receipt of a monetary reward relative to a loss in healthy adults. We hypothesized that MA (vs. placebo) would increase mesolimbic neural activation to reward, relative to loss.

METHODS

In a within-subject, randomized, cross-over, double-blind, placebo-controlled design, 41 healthy adults completed the Doors monetary reward task during fMRI after ingestion of placebo or 20 mg MA. We examined drug effects on neural response to reward receipt (Win vs. Loss) using a priori anatomical striatal regions of interest (nucleus accumbens (NAcc), caudate, putamen).

RESULTS

MA decreased NAcc BOLD activation to reward vs loss compared to placebo (p=.007) without altering caudate or putamen BOLD activation. Similar effects for reward vs. loss were obtained using whole brain analysis. Additional exploratory ROI analysis comparing reward and loss activation relative to a neutral "fixation" period indicated that MA increased NAcc BOLD activation during loss trials, without decreasing activation during win trials.

CONCLUSIONS

This preliminary evidence suggests that MA increases NAcc neural response to the receipt of monetary loss. Additional studies are needed to replicate our findings and clarify the mechanisms contributing to altered mesolimbic neural response to reward and loss receipt during stimulant intoxication.

Influence of reconsolidation in maintenance of cocaine-associated contextual memories formed during adolescence or adulthood

Adolescents are at increased risk to develop substance use disorders and suffer from relapse throughout life. Targeted weakening of drug-associated memories has been shown to reduce relapse-like behavior in adult rats, however this process has been understudied in adolescents. We aimed to examine whether adolescent-formed, cocaine-associated memories could be manipulated via reconsolidation mechanisms. To accomplish this objective, we used an abbreviated operant cocaine self-administration paradigm (ABRV Coc-SA). Adult and adolescent rats received jugular catheterization surgery followed by ABRV Coc-SA in a distinct context for 2 h, 2×/day over 5 days. Extinction training (EXT) occurred in a second context for 2 h, 2×/day over 4 days. To retrieve cocaine-context memories, rats were exposed to the cocaine-paired context for 15 min, followed by subcutaneous injection of vehicle or the protein synthesis inhibitor cycloheximide (2.5 mg/kg). Two additional EXT sessions were conducted before a 2 h reinstatement test in the cocaine-paired context to assess cocaine-seeking behavior. We find that both adult and adolescent cocaine-exposed rats show similar levels of cocaine-seeking behavior regardless of post-reactivation treatment. Our results suggest that systemic treatment with the protein synthesis inhibitor cycloheximide does not impair reconsolidation of cocaine-context memories and subsequent relapse during adulthood or adolescence.

Plasma concentrations of lysophosphatidic acid and the expression of its receptors in peripheral blood mononuclear cells are altered in patients with cocaine use disorders

We have recently reported alterations in the plasma concentrations of lysophosphatidic acid (LPA) in patients with substance use disorders. In order to further explore the potential role of the LPA signaling system as biomarker in cocaine use disorders (CUD) we conducted a cross-sectional study with 105 patients diagnosed with CUD and 92 healthy controls. Participants were clinically evaluated and blood samples were collected to determine plasma concentrations of total LPA and LPA species (16:0-, 18:0-, 18:1-, 18:2-, and 20:4-LPA), and the gene expression of LPA₁ and LPA₂ receptors in peripheral blood mononuclear cells. We found that patients with CUD had significantly lower plasma concentration of the majority of LPA species, while the mRNA expression of LPA₁ receptor was found to be higher than controls. Moreover, we found a positive association between plasma concentration of 20:4-LPA and relevant CUD-related variables: age of onset cocaine use and length of cocaine abstinence. The statistical analysis revealed sex differences in concentrations of total LPA and LPA species, and women showed higher LPA concentrations than men. Furthermore, studies in rats of both sexes showed that plasma concentrations of total LPA were also altered after acute and chronic cocaine administration, revealing a sexual dimorphism in these effects. This study found alterations on the LPA signaling system in both, patients with CUD and rats treated with cocaine. Our results demonstrate that LPA signaling is impacted by CUD and sex, which must be taken into consideration in future studies evaluating LPA as a reliable biomarker for CUD.

Trends in Self-reported and Biochemically Verified Cocaine and Methamphetamine Use Among Pregnant Individuals in Northern California, 2011-2019

This cross-sectional study uses data from the Kaiser Permanente Northern California health care system with universal screening via self-report and urine toxicology at prenatal care entrance to examine trends in cocaine and methamphetamine use among pregnant individuals from 2011 to 2019.

Neural substrates of substance use disorders

PURPOSE OF REVIEW

Substance use disorders account for a tremendous burden to society, yet despite substantial progress in basic studies, our understanding of the brain-basis of these disorders is still emerging. This review summarizes the recent findings of neuroimaging studies with substance use disorder individuals.

RECENT FINDINGS

Resting-state functional connectivity studies support for some but not all substances of abuse and disruption in executive control. Structural neuroimaging findings point towards reduced subcortical volumes, which may emerge as an interaction between preexisting factors and recent substance use. Longitudinal studies implicate some of the same core brain structures and their functional role that have also been identified via case-control studies. Finally, meta-analyses support the idea of dysregulation of cortical control over subcortical salience processing.

SUMMARY

Although progress has been made and there is both structural and functional imaging evidence of an imbalance between brain structures involved in executive control and salience processing, there is emerging evidence that brain-behaviour relationships, which are core to discovering the neural processes that lead to and maintain substance use, are small and require larger consortia that prospectively examine individuals with substance use disorder.

Clinical Correlates and Outcomes of Methamphetamine-Associated Cardiovascular Diseases in Hospitalized Patients in California

Background

Methamphetamine misuse affects 27 million people worldwide and is associated with cardiovascular disease (CVD); however, risk factors for CVD among users have not been well studied.

Methods and Results

We studied hospitalized patients in California, captured by the Healthcare Cost and Utilization Project database, between 2005 and 2011. We studied the association between methamphetamine use and CVD (pulmonary hypertension, heart failure, stroke, and myocardial infarction). Among 20 249 026 persons in the Healthcare Cost and Utilization Project, 66 199 used methamphetamines (median follow‐up 4.58 years). Those who used were more likely younger (33 years versus 45 years), male (63.3% versus 44.4%), smoked, misused alcohol, and had depression and anxiety compared with nonusers. Methamphetamine use was associated with the development of heart failure (hazard ratio [HR], 1.53 [95% CI, 1.45–1.62]) and pulmonary hypertension (HR, 1.42 [95% CI, 1.26–1.60]). Among users, male sex (HR, 1.73 [95% CI, 1.37–2.18]) was associated with myocardial infarction. Chronic kidney disease (HR, 2.38 [95% CI, 1.74–3.25]) and hypertension (HR, 2.26 [95% CI, 2.03–2.51]) were strong risk factors for CVD among users. When compared with nonuse, methamphetamine use was associated with a 32% significant increase in CVD, alcohol abuse with a 28% increase, and cocaine use with a 47% increase in CVD.

Conclusions

Methamphetamine use has a similar magnitude of risk of CVD compared with alcohol and cocaine. Prevention and treatment could be focused on those with chronic kidney disease, hypertension, and mental health disorders.