A short review on the aetiology and pathophysiology of alcoholism

Modeling SARS-CoV-2 infection in individuals with opioid use disorder with brain organoids

The COVID-19 pandemic has aggravated a preexisting epidemic: the opioid crisis. Much literature has shown that the circumstances imposed by COVID-19, such as social distancing regulations, medical and financial instability, and increased mental health issues, have been detrimental to those with opioid use disorder (OUD). In addition, unexpected neurological sequelae in COVID-19 patients suggest that COVID-19 compromises neuroimmunity, induces hypoxia, and causes respiratory depression, provoking similar effects as those caused by opioid exposure. Combined conditions of COVID-19 and OUD could lead to exacerbated complications. With limited human in vivo options to study these complications, we suggest that iPSC-derived brain organoid models may serve as a useful platform to investigate the physiological connection between COVID-19 and OUD. This mini-review highlights the advances of brain organoids in other neuropsychiatric and infectious diseases and suggests their potential utility for investigating OUD and COVID-19, respectively.

Alcohol consumption and incidence of sleep disorder: A systematic review and meta-analysis of cohort studies

OBJECTIVE

To investigate the association between alcohol consumption and incidence of sleep disorder.

METHODS

PubMed, EMBASE and OVID were searched systematically until March 2020 for cohort studies quantitatively investigating the effect of alcohol on incident sleep disorder. We conducted a random-effects meta-analysis to calculate the summary ORs (odds ratios) and 95 %CIs (confidence intervals) on the incidence of sleep disorder in relation to alcohol consumption.

RESULTS

The pooled analysis of eleven included cohort studies demonstrated that general drinking was significantly associated with incidence of sleep disorder (OR:1.37, 95 %CI:1.22,1.54,I² = 0.0 %) while heavy drinking was not (OR:1.22, 95 %CI:0.94,1.60, I² = 81.1 %). (general drinking (women <24 g/day; men <48 g/day; < 4 times/week), heavy drinking (women ≥24 g/day; men ≥48 g/day; ≥ 4times/week)).

CONCLUSIONS

Findings from the present systematic review and meta-analyses showed that there was no evidence that alcohol consumption diminished sleep problems, and some evidence that general drinking might increase the sleep problems, but further study is necessary.

Using human stem cells as a model system to understand the neural mechanisms of alcohol use disorders: Current status and outlook

Alcohol use disorders (AUDs), which include alcohol abuse and dependence, are among the most common types of neuropsychiatric disorders in the United States (U.S.). Approximately 14% of the U.S. population is affected in a single year, thus placing a tremendous burden on individuals from all socioeconomic backgrounds. Animal models have been pivotal in revealing the basic mechanisms of how alcohol impacts neuronal function, yet there are currently limited effective therapies developed based on these studies. This is mainly due to a limited understanding of the exact cellular and molecular mechanisms underlying AUDs in humans, which leads to a lack of targeted therapeutics. Furthermore, compounding factors including genetic background, gene copy number variants, single nucleotide polymorphisms (SNP) as well as environmental and social factors that affect and promote the development of AUDs are complex and heterogeneous. Recent developments in stem cell biology, especially the human induced pluripotent stem (iPS) cell development and differentiation technologies, has provided us a unique opportunity to model neuropsychiatric disorders like AUDs in a manner that is highly complementary to animal studies, but that maintains fidelity with complex human genetic contexts. Patient-specific neuronal cells derived from iPS cells can then be used for drug discovery and precision medicine, e.g. for pathway-directed development in alcoholism. Here, we review recent work employing iPS cell technology to model and elucidate the genetic, molecular and cellular mechanisms of AUDs in a human neuronal background and provide our perspective on future development in this direction.

Polysomnographic sleep disturbances in nicotine, caffeine, alcohol, cocaine, opioid, and cannabis use: A focused review

BACKGROUND AND OBJECTIVES

In the United States, approximately 60 million Americans suffer from sleep disorders and about 22 million Americans report substance dependence or use disorders annually. Sleep disturbances are common consequences of substance use disorders and are likely found in primary care as well as in specialty practices. The aim of this review was to evaluate the effects of the most frequently used substances-nicotine, alcohol, opioids, cocaine, caffeine, and cannabis-have on sleep parameters measured by polysomnography (PSG) and related clinical manifestations.

METHODS

We used electronic databases such as PubMED and PsycINFO to search for relevant articles. We only included studies that assessed sleep disturbances using polysomnography and reviewed the effects of these substances on six clinically relevant sleep parameters: Total sleep time, sleep onset latency, rapid-eye movement, REM latency, wake after sleep onset, and slow wave sleep.

RESULTS

Our review indicates that these substances have significant impact on sleep and that their effects differ during intoxication, withdrawal, and chronic use. Many of the substance-induced sleep disturbances overlap with those encountered in sleep disorders, medical, and psychiatric conditions. Sleep difficulties also increase the likelihood of substance use disorder relapse, further emphasizing the need for optimizing treatment interventions in these patients.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

Our review highlights the importance of systematically screening for substance use in patients with sleep disturbances and highlights the need for further research to understand mechanisms underlying substances-induced sleep disturbances and on effective interventions addressing these conditions.

Probability and predictors of transition from first use to dependence on nicotine, alcohol, cannabis, and cocaine: results of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC)

BACKGROUND

This study aims to estimate general and racial-ethnic specific cumulative probability of developing dependence among nicotine, alcohol, cannabis or cocaine users, and to identify predictors of transition to substance dependence.

METHODS

Analyses were done for the subsample of lifetime nicotine (n=15,918), alcohol (n=28,907), cannabis (n=7389) or cocaine (n=2259) users who participated in the first and second wave of the National Epidemiological Survey on Alcohol and Related Conditions (NESARC). Discrete-time survival analyses were implemented to estimate the cumulative probability of transitioning from use to dependence and to identify predictors of transition to dependence.

RESULTS

The cumulative probability estimate of transition to dependence was 67.5% for nicotine users, 22.7% for alcohol users, 20.9% for cocaine users, and 8.9% for cannabis users. Half of the cases of dependence on nicotine, alcohol, cannabis and cocaine were observed approximately 27, 13, 5 and 4 years after use onset, respectively. Significant racial-ethnic differences were observed in the probability of transition to dependence across the four substances. Several predictors of dependence were common across the four substances assessed.

CONCLUSIONS

Transition from use to dependence was highest for nicotine users, followed by cocaine, alcohol and cannabis users. Transition to cannabis or cocaine dependence occurred faster than transition to nicotine or alcohol dependence. The existence of common predictors of transition dependence across substances suggests that shared mechanisms are involved. The increased risk of transition to dependence among individuals from minorities or those with psychiatric or dependence comorbidity highlights the importance of promoting outreach and treatment of these populations.