Crack-cocaine dependence and aging: effects on working memory

Molecular signatures of premature aging in Major Depression and Substance Use Disorders

Major depressive disorder (MDD) and substance-use disorders (SUDs) often lead to premature aging, increasing vulnerability to cognitive decline and other forms of dementia. This study utilized advanced systems bioinformatics to identify aging "signatures" in MDD and SUDs and evaluated the potential for known lifespan-extending drugs to target and reverse these signatures. The results suggest that inhibiting the transcriptional activation of FOS gene family members holds promise in mitigating premature aging in MDD and SUDs. Conversely, antidepressant drugs activating the PI3K/Akt/mTOR pathway, a common mechanism in rapid-acting antidepressants, may accelerate aging in MDD patients, making them unsuitable for those with comorbid aging-related conditions like dementia and Alzheimer's disease. Additionally, this innovative approach identifies potential anti-aging interventions for MDD patients, such as Deferoxamine, Resveratrol, Estradiol valerate, and natural compounds like zinc acetate, genistein, and ascorbic acid, regardless of comorbid anxiety disorders. These findings illuminate the premature aging effects of MDD and SUDs and offer insights into treatment strategies for patients with comorbid aging-related conditions, including dementia and Alzheimer's disease.

Ageing and older people who use illicit opioids, cocaine or methamphetamine: a scoping review and literature map

AIMS

To provide an overview of research literature on ageing and older people who use illicit opioids and stimulants by documenting the conceptual frameworks used and content areas that have been investigated.

METHODS

We conducted a scoping review of literature relating to ageing and older people who use illicit stimulants and opioids, defining 'older' as 40 years and above. Primary studies, secondary studies and editorials were included. Searches were conducted in PubMed and Embase in July 2020 and March 2021; the Cochrane library was searched in November 2021. Charted data included methodological details, any conceptual frameworks explicitly applied by authors and the content areas that were the focus of the publication. We developed a hierarchy of content areas and mapped this to provide a visual guide to the research area.

RESULTS

Of the 164 publications included in this review, only 16 explicitly applied a conceptual framework. Seven core content areas were identified, with most publications contributing to multiple content areas: acknowledgement of drug use among older people (n = 64), health status (n = 129), health services (n = 109), drug use practices and patterns (n = 84), social environments (n = 74), the criminal legal system (n = 28) and quality of life (n = 15).

CONCLUSIONS

The literature regarding older people who use illicit drugs remains under-theorized. Conceptual frameworks are rarely applied and few have been purposely adapted to this population. Health status and health services access and use are among the most frequently researched topics in this area.

Cocaine: An Updated Overview on Chemistry, Detection, Biokinetics, and Pharmacotoxicological Aspects including Abuse Pattern

Cocaine is one of the most consumed stimulants throughout the world, as official sources report. It is a naturally occurring sympathomimetic tropane alkaloid derived from the leaves of Erythroxylon coca, which has been used by South American locals for millennia. Cocaine can usually be found in two forms, cocaine hydrochloride, a white powder, or ‘crack’ cocaine, the free base. While the first is commonly administered by insufflation (‘snorting’) or intravenously, the second is adapted for inhalation (smoking). Cocaine can exert local anaesthetic action by inhibiting voltage-gated sodium channels, thus halting electrical impulse propagation; cocaine also impacts neurotransmission by hindering monoamine reuptake, particularly dopamine, from the synaptic cleft. The excess of available dopamine for postsynaptic activation mediates the pleasurable effects reported by users and contributes to the addictive potential and toxic effects of the drug. Cocaine is metabolised (mostly hepatically) into two main metabolites, ecgonine methyl ester and benzoylecgonine. Other metabolites include, for example, norcocaine and cocaethylene, both displaying pharmacological action, and the last one constituting a biomarker for co-consumption of cocaine with alcohol. This review provides a brief overview of cocaine’s prevalence and patterns of use, its physical-chemical properties and methods for analysis, pharmacokinetics, pharmacodynamics, and multi-level toxicity.

Exploring the Relationship Between Substance Use and Allostatic Load in a Treatment/Research Cohort and in a US Probability Sample (NHANES 2009-2016)

Allostatic load, an operationalization for cumulative strain on physiology from adaptation (allostasis) to stress over a lifetime, can manifest as damage to cardiovascular, neuroendocrine, and metabolic systems. The concept of allostatic load may be particularly useful in research on substance-use disorders (SUDs) because SUD researchers have sought to better understand the relationship between chronic stressors and drug use. Theoretical models hold that SUDs can be conceptualized as a spiral toward a state of persistent allostasis (i.e., allostasis so persistent as to represent homeostasis at a new, unhealthy set point). Regardless of the extent to which those models are accurate, increased allostatic load could be a mechanism by which frequent drug administration increases risk for adverse outcomes. We conducted two secondary analyses to evaluate allostatic load in the context of drug use, including alcohol use, in a locally recruited sample with a high proportion of illicit substance use (N = 752) and in a nationally representative sample from the NHANES 2009-2016. We hypothesized that after controlling for age and other potential confounds, people with longer histories of drug use would have higher allostatic-load scores. Multiple regression was used to predict allostatic load from participants' drug-use histories while controlling for known confounds. In the locally recruited sample, we found that longer lifetime use of cocaine or opioids was related to increased allostatic load. In NHANES 2009-2016, we found few or no such associations. Lengthy histories of problematic non-medical substance use may facilitate more rapid increases in allostatic load than aging alone, and, together with findings from previous investigations, this finding suggests increased risk for chronic disease.

The Challenge by Multiple Environmental and Biological Factors Induce Inflammation in Aging: Their Role in the Promotion of Chronic Disease

The aging process is driven by multiple mechanisms that lead to changes in energy production, oxidative stress, homeostatic dysregulation and eventually to loss of functionality and increased disease susceptibility. Most aged individuals develop chronic low-grade inflammation, which is an important risk factor for morbidity, physical and cognitive impairment, frailty, and death. At any age, chronic inflammatory diseases are major causes of morbimortality, affecting up to 5-8% of the population of industrialized countries. Several environmental factors can play an important role for modifying the inflammatory state. Genetics accounts for only a small fraction of chronic-inflammatory diseases, whereas environmental factors appear to participate, either with a causative or a promotional role in 50% to 75% of patients. Several of those changes depend on epigenetic changes that will further modify the individual response to additional stimuli. The interaction between inflammation and the environment offers important insights on aging and health. These conditions, often depending on the individual's sex, appear to lead to decreased longevity and physical and cognitive decline. In addition to biological factors, the environment is also involved in the generation of psychological and social context leading to stress. Poor psychological environments and other sources of stress also result in increased inflammation. However, the mechanisms underlying the role of environmental and psychosocial factors and nutrition on the regulation of inflammation, and how the response elicited for those factors interact among them, are poorly understood. Whereas certain deleterious environmental factors result in the generation of oxidative stress driven by an increased production of reactive oxygen and nitrogen species, endoplasmic reticulum stress, and inflammation, other factors, including nutrition (polyunsaturated fatty acids) and behavioral factors (exercise) confer protection against inflammation, oxidative and endoplasmic reticulum stress, and thus ameliorate their deleterious effect. Here, we discuss processes and mechanisms of inflammation associated with environmental factors and behavior, their links to sex and gender, and their overall impact on aging.

Predictors of Antiretroviral Adherence Self-efficacy Among People Living With HIV/AIDS in a Canadian Setting

BACKGROUND

Suboptimal adherence to antiretroviral therapy (ART) among people living with HIV/AIDS (PLWHA) who use illicit drugs remains an ongoing health concern. Although health outcomes associated with adherence self-efficacy have been well-documented, there is dearth research exploring the predictors of this construct. This study sought to identify possible determinants of adherence self-efficacy among a cohort of PLWHA who use illicit drugs.

METHODS

From December 2004 to May 2014, we collected data from the AIDS Care Cohort to evaluate Exposure to Survival Services, a prospective cohort of adult PLWHA who use illicit drugs in Vancouver, Canada. We used multivariate generalized estimating equation analyses to identify longitudinal factors independently associated with higher adherence self-efficacy.

RESULTS

Among 742 participants, 493 (66.4%) identified as male and 406 (54.7%) reported white ancestry. In multivariate generalized estimating equation analysis, older age at ART initiation (adjusted odds ratio [AOR] = 1.02, 95% confidence interval [CI]: 1.00 to 1.03) and recent year of baseline interview (AOR = 1.08, 95% CI: 1.05 to 1.11) were independently associated with higher adherence self-efficacy, whereas homelessness (AOR = 0.78, 95% CI: 0.65 to 0.94), ≥daily crack smoking (AOR = 0.81, 95% CI: 0.68 to 0.96), experienced violence (AOR = 0.82, 95% CI: 0.69 to 0.98), and childhood abuse (AOR = 0.75, 95% CI: 0.60 to 0.92) were negatively associated.

CONCLUSIONS

These findings highlight the potential role that personal and contextual factors can play in predicting levels of ART adherence self-efficacy. Future research should seek to identify and validate strategies to optimize adherence self-efficacy.

Cognitive function in aging cocaine smokers

BACKGROUND

Little is known about the functional status of older drug users, who may pose challenges to public health systems in coming years. Here, we assessed cognitive function in aging cocaine smokers compared to demographically matched controls.

METHODS

A total of 22 non-treatment-seeking aging (50-60 years old) cocaine smokers (⩾twice/week; ⩾15 years of weekly use) and 19 controls completed a comprehensive cognitive battery. Controls with cannabis, tobacco, and alcohol use were included to better match the cocaine users. All cocaine users, and current cannabis- or alcohol-using controls, completed testing after 4 drug-free inpatient days to better control for acute and residual drug effects.

RESULTS

Cocaine users (52.9 ± 2.5 years old, four female; cocaine use 3.9 ± 1.4 days/week) and controls (52.7 ± 2.6 years old, four female) were well matched demographically, but cocaine users reported a more extensive substance use profile. Cocaine users showed marginally worse verbal learning than controls, recalling on average one word fewer across immediate and delayed word recall trials. Their performance was intact relative to controls across all other measures of cognitive function. Bayesian analysis indicated the absence of group differences was not due to power limitations.

CONCLUSION

These data suggest that aging, long-term cocaine users have similar cognitive functioning to appropriately matched controls when tested under drug-free conditions, with only marginal decreases in verbal learning. Findings, although reassuring with regard to broad cognitive capacities in aging cocaine smokers, suggest that future investigations of cognitive function in aging drug users are warranted.

Telomere length in psychiatric disorders: Is it more than an ageing marker?

OBJECTIVES

Psychiatric and substance-use disorders have been associated with premature biological ageing. Telomere length (TL), considered an ageing marker, has been analysed in psychiatric disorders, and to a lesser extent in substance-use disorders, with recent findings suggesting TL may be related to disease pathology.

METHODS

We conducted a critical and non-systematic literature search of TL studies published up to June 2016 in psychiatric and substance-use disorders, focussing on studies describing mechanisms, including studies linking telomere biology with genetic factors, stress and mitochondrial alterations (104 studies selected).

RESULTS

Patients with major depressive disorder and anxiety appear to have shorter leukocyte telomeres compared to controls. Inconclusive results are found for other psychiatric disorders and for substance-use disorders. This may be due in part to differences in medication treatment and response, as studies suggest that some psychotropic medications may modulate TL. Importantly, some studies establish a relationship between telomere machinery, stress and mitochondria function in psychiatric and substance-use disorders.

CONCLUSIONS

While further longitudinal studies considering telomere genetics are needed to clarify the cause-effect link between telomeres and mitochondria function in psychiatric and substance-use disorders, the recent findings linking these biological processes suggest that telomeres may be more than ageing markers.

Interaction Between Stress and Addiction: Contributions From Latin-American Neuroscience

Drug addiction is a chronic neuropsychiatric disorder that escalates from an initial exposure to drugs of abuse, such as cocaine, cannabis, or heroin, to compulsive drug-seeking and intake, reduced ability to inhibit craving-induced behaviors, and repeated cycles of abstinence and relapse. It is well-known that chronic changes in the brain’s reward system play an important role in the neurobiology of addiction. Notably, environmental factors such as acute or chronic stress affect this system, and increase the risk for drug consumption and relapse. Indeed, the HPA axis, the autonomic nervous system, and the extended amygdala, among other brain stress systems, interact with the brain’s reward circuit involved in addictive behaviors. There has been a growing interest in studying the molecular, cellular, and behavioral mechanisms of stress and addiction in Latin-America over the last decade. Nonetheless, these contributions may not be as strongly acknowledged by the broad scientific audience as studies coming from developed countries. In this review, we compile for the first time a series of studies conducted by Latin American-based neuroscientists, who have devoted their careers to studying the interaction between stress and addiction, from a neurobiological and clinical perspective. Specific contributions about this interaction include the study of CRF receptors in the lateral septum, investigations on the neural mechanisms of cross-sensitization for psychostimulants and ethanol, the identification of the Wnt/β-catenin pathway as a critical neural substrate for stress and addiction, and the emergence of the cannabinoid system as a promising therapeutic target. We highlight animal and human studies, including for instance, reports coming from Latin American laboratories on single nucleotide polymorphisms in stress-related genes and potential biomarkers of vulnerability to addiction, that aim to bridge the knowledge from basic science to clinical research.

Impulsivity and decision making in older and younger cocaine-dependent participants: A preliminary study

BACKGROUND AND OBJECTIVES

Substance misuse is increasing in the older population, which may have differing effects on behavior compared to younger substance participants. Differences in trait and state impulsivity were assessed in younger and older cocaine-dependent participants.

METHODS

Thirty-one younger cocaine-dependent participants (n = 31) and 21 older cocaine-dependent participants (n = 21) were assessed using the Barrett Impulsiveness Scale-11 and the Immediate Memory Task.

RESULTS

Younger participants showed higher trait impulsivity than older participants (p =.027). However, older participants demonstrated higher state impulsivity than younger participants (p =.018).

CONCLUSION

Higher state impulsivity in older cocaine participants suggests that cocaine use may have accelerating effects on the aging brain.

SCIENTIFIC SIGNIFICANCE

This preliminary study adds the limited research on how cocaine use affects normal aging. Current treatments are based on younger adults, therefore the needs of older adults should be taken into consideration and studied more. (Am J Addict 2018;27:557-559).

The Role of Working Memory for Cognitive Control in Anorexia Nervosa versus Substance Use Disorder

Prefrontal cortex executive functions, such as working memory (WM) interact with limbic processes to foster impulse control. Such an interaction is referred to in a growing body of publications by terms such as cognitive control, cognitive inhibition, affect regulation, self-regulation, top-down control, and cognitive–emotion interaction. The rising trend of research into cognitive control of impulsivity, using various related terms reflects the importance of research into impulse control, as failure to employ cognitions optimally may eventually result in mental disorder. Against this background, we take a novel approach using an impulse control spectrum model – where anorexia nervosa (AN) and substance use disorder (SUD) are at opposite extremes – to examine the role of WM for cognitive control. With this aim, we first summarize WM processes in the healthy brain in order to frame a systematic review of the neuropsychological, neural and genetic findings of AN and SUD. In our systematic review of WM/cognitive control, we found n = 15 studies of AN with a total of n = 582 AN and n = 365 HC participants; and n = 93 studies of SUD with n = 9106 SUD and n = 3028 HC participants. In particular, we consider how WM load/capacity may support the neural process of excessive epistemic foraging (cognitive sampling of the environment to test predictions about the world) in AN that reduces distraction from salient stimuli. We also consider the link between WM and cognitive control in people with SUD who are prone to ‘jumping to conclusions’ and reduced epistemic foraging. Finally, in light of our review, we consider WM training as a novel research tool and an adjunct to enhance treatment that improves cognitive control of impulsivity.

Crack cocaine inhalation induces schizophrenia-like symptoms and molecular alterations in mice prefrontal cortex

Crack cocaine (crack) addiction represents a major social and health burden, especially seeing as users are more prone to engage in criminal and violent acts. Crack users show a higher prevalence of psychiatric comorbidities - particularly antisocial personality disorders - when compared to powder cocaine users. They also develop cognitive deficits related mainly to executive functions, including working memory. It is noteworthy that stimulant drugs can induce psychotic states, which appear to mimic some symptoms of schizophrenia among users. Social withdraw and executive function deficits are, respectively, negative and cognitive symptoms of schizophrenia mediated by reduced dopamine (DA) tone in the prefrontal cortex (PFC) of patients. That could be explained by an increased expression of D2R short isoform (D2S) in the PFC of such patients and/or by hypofunctioning NMDA receptors in this region. Reduced DA tone has already been described in the PFC of mice exposed to crack smoke. Therefore, it is possible that behavioral alterations presented by crack users result from molecular and biochemical neuronal alterations akin to schizophrenia. Accordingly, we found that upon crack inhalation mice have shown decreased social interaction and working memory deficits analogous to schizophrenia's symptoms, along with increased D2S/D2L expression ratio and decreased expression of NR1, NR2A and NR2B NMDA receptor subunits in the PFC. Herein we propose two possible mechanisms to explain the reduced DA tone in the PFC elicited by crack consumption in mice, bringing also the first direct evidence that crack use may result in schizophrenia-like neurochemical, molecular and behavioral alterations.

Is biological aging accelerated in drug addiction?

Drug-addiction may trigger early onset of age-related disease, due to drug-induced multi-system toxicity and perilous lifestyle, which remains mostly undetected and untreated. We present the literature on pathophysiological processes that may hasten aging and its relevance to addiction, including: oxidative stress and cellular aging, inflammation in periphery and brain, decline in brain volume and function, and early onset of cardiac, cerebrovascular, kidney, and liver disease. Timely detection of accelerated aging in addiction is crucial for the prevention of premature morbidity and mortality.

Crack cocaine addiction, early life stress and accelerated cellular aging among women

BACKGROUND

Early life stress (ELS) and addiction are related to age-related diseases and telomere shortening. However, the role of telomere length (TL) in crack cocaine addiction remains unknown. The purpose of this study was to investigate the TL in a sample of crack cocaine dependent-women who reported an ELS history and in a community-based sample of elderly women as a reference group for senescence.

METHODS

This study included treatment seeking crack cocaine dependents women (n=127) and elderly women without a psychiatric diagnosis (ELD, n=49). The crack cocaine sample was divided in two groups according to their Childhood Trauma Questionnaire (CTQ) scores: presence of history of childhood abuse and neglect (CRACK-ELS) and absence of ELS history (CRACK). TL was assessed by T/S ratio obtained from peripheral blood DNA using quantitative PCR assay.

RESULTS

CRACK and CRACK-ELS subjects exhibited shortened TL in comparison to the ELD group, despite their younger age. Among crack cocaine sample, CRACK-ELS group had significantly shorter telomeres than the CRACK group. Correlation analysis within crack cocaine group indicated that TL was negatively correlated with emotional abuse scores.

CONCLUSIONS

These results support previous findings associating telomere shortening with both ELS and drug addiction. This study suggests new evidence of a distinct biological phenotype for drug-dependent women with ELS. The results support the biological senescence hypothesis underpinning ELS experience.