Use of methylphenidate and reporting of valvular heart disease: Global pharmacovigilance analysis in children and adults.

INTRODUCTION: Methylphenidate (MPH) is a common treatment of attention-deficit/hyperactivity disorder (ADHD). Concern has been raised regarding its cardiovascular safety, partly in relation with its micromolar affinity for the 5-HT2B receptor, whose activation may result in valvular heart disease (VHD). METHODS: To explore the association between the use of MPH and VHD reporting, we performed a disproportionality analysis within the WHO global safety database (VigiBase) using data, since inception until March 6th 2024, from: (i) the full database and (ii) different age groups (children/adolescents 6-17 years; adults 18-64 years). To avoid competition bias, safety reports with amphetamine-like appetite suppressants were excluded. Disproportionality was expressed using reporting odds-ratio (ROR) and its 95% confidence interval (CI). RESULTS: Of 29 129 spontaneous reports with MPH, 23 VHD cases (7.9 per 10 000 reports) were identified, including 13 adults and 10 children. Most cases concerned injury on the mitral valve. A disproportionate reporting was observed overall (ROR 1.6, 95% CI 1.1-2.4). Analysis according to age group found that disproportionality in VHD reporting was found in adults only (ROR 2.7, 95% CI 1.6-4.7) but not in children/adolescents (ROR 1.7, 95% CI 0.9-3.2). Furthermore, amongst MPH users only, VHD reporting was higher in adults compared to children (ROR 2.7, 95% CI 1.2-6.3). CONCLUSION: VHD reporting appears rare with MPH compared to other adverse events and is increased in adults only. Our findings support a potential safety signal of VHD in adults exposed to MPH. A risk in that population cannot be excluded and requires further assessment.

Assessment of centanafadine in adults with attention-deficit/hyperactivity disorder: A matching-adjusted indirect comparison vs lisdexamfetamine dimesylate, atomoxetine hydrochloride, and viloxazine extended-release.

BACKGROUND: Head-to-head trials comparing centanafadine, an investigational therapy for adults with attention-deficit/hyperactivity disorder (ADHD), with other treatment options are lacking. OBJECTIVE: To compare safety and efficacy outcomes of centanafadine sustained-release vs lisdexamfetamine dimesylate (lisdexamfetamine), atomoxetine hydrochloride (atomoxetine), and viloxazine extended-release (viloxazine ER), respectively, using matching-adjusted indirect comparison (MAIC). METHODS: This MAIC included patient-level data pooled from 2 centanafadine trials (NCT03605680 and NCT03605836) and published aggregate data from comparable trials of 3 comparators-lisdexamfetamine (NCT00334880), atomoxetine (NCT00190736), and viloxazine ER (NCT04016779)-in adult patients with ADHD. Propensity score weighting was used to match characteristics of individual patients from the centanafadine trials to aggregate baseline characteristics from the respective comparator trials. Safety outcomes were rates of adverse events for which information was available in the centanafadine and respective comparator trials. Efficacy outcome was mean change from baseline in the Adult ADHD Investigator Symptom Rating Scale (AISRS) score (ADHD Rating Scale [ADHD-RS] was used as proxy in the comparison with lisdexamfetamine). Anchored indirect comparisons were conducted across matched populations of the centanafadine and respective comparator trials. RESULTS: After matching, baseline characteristics in the centanafadine trials were the same as those in the respective comparator trials. Compared with lisdexamfetamine, centanafadine was associated with a significantly lower risk of lack of appetite (risk difference [RD] in percentage points: 23.42), dry mouth (19.27), insomnia (15.35), anxiety (5.21), nausea (4.90), feeling jittery (3.70), and diarrhea (3.47) (all P < 0.05) but a smaller reduction in the AISRS/ADHD-RS score (6.58-point difference; P < 0.05). Compared with atomoxetine, centanafadine was associated with a significantly lower risk of nausea (RD in percentage points: 18.64), dry mouth (17.44), fatigue (9.21), erectile dysfunction (6.76), lack of appetite (6.71), and urinary hesitation (5.84) (all P < 0.05) and no statistically significant difference in the change in AISRS score. Compared with viloxazine ER, centanafadine was associated with a significantly lower risk of fatigue (RD in percentage points: 11.07), insomnia (10.67), nausea (7.57), and constipation (4.63) (all P < 0.05) and no statistically significant difference in the change in AISRS score. CONCLUSIONS: In an anchored MAIC, centanafadine showed a significantly better short-term safety profile than lisdexamfetamine, atomoxetine, and viloxazine ER; efficacy was lower than with lisdexamfetamine and comparable (ie, nondifferent) with atomoxetine and viloxazine ER. This MAIC provides important insights on the relative safety and efficacy of common treatment options to help inform treatment decisions in adults with ADHD. Safety assessment was limited to rates of adverse events reported in both trials of a given comparison. STUDY REGISTRATION NUMBERS: NCT03605680, NCT03605836, NCT00334880, NCT00190736, and NCT04016779.

Long-Term Cardiovascular Risk Associated With Treatment of Attention-Deficit/Hyperactivity Disorder in Adults.

BACKGROUND: Incrementing numbers of patients treated for attention-deficit/hyperactivity disorder (ADHD) call for scrutiny concerning long-term drug-safety. OBJECTIVES: This study aims to investigate associations between long-term use of ADHD treatment and cardiovascular outcomes. METHODS: Using nationwide registers, adult patients first-time initiated on ADHD treatment between 1998 and 2020 were identified. Exposure groups were prior users, <1 defined daily dose (DDD) per day, ≥1 DDD per day determined at start of follow-up, and 1 year after patients' first claimed prescription. Outcomes were acute coronary syndromes, stroke, heart failure, and a composite of the above. RESULTS: At start of follow-up, 26,357, 31,211, and 15,696 individuals were correspondingly categorized as prior users (42% female, median age: 30 years [Q1-Q3: 23-41 years]), <1 DDD per day (47% female, median age: 31 years [Q1-Q3: 24-41 years]), and ≥1 DDD per day (47% female, median age: 33 years [Q1-Q3: 25-41 years]), respectively. Comparing ≥1 DDD per day with prior users, elevated standardized 10-year absolute risk of stroke (2.1% [95% CI: 1.8%-2.4%] vs 1.7% [95% CI: 1.5%-1.9%]), heart failure (1.2% [95% CI: 0.9%-1.4%] vs 0.7% [95% CI: 0.6%-0.8%]), and the composite outcome (3.9% [95% CI: 3.4%-4.3%] vs 3.0% [95% CI: 2.8 %-3.2%]) was found-with corresponding risk ratios of 1.2 (95% CI: 1.0-1.5), 1.7 (95% CI: 1.3-2.2), and 1.3 (95% CI: 1.1-1.5). No apparent associations were found for acute coronary syndrome (1.0% [95% CI: 0.8%-1.2%] vs 0.9% [95% CI: 0.8%-1.0%]). CONCLUSIONS: Possible associations between elevated long-term cardiovascular risk and increasing dosage of ADHD treatment use in a young patient group should warrant further investigation.

Adults with both bipolar disorder and ADHD.

ADHD and bipolar disorder (BP) commonly coexist, and both share key symptoms, depending on affective state and emotional dysregulation. The overlap poses diagnostic challenges and may lead to underdiagnoses. Comorbid cases exhibit worsened symptom burden, increased psychiatric morbidity, admissions, and suicide attempts. Treating BP before ADHD is recommended. Stimulant use combined with mood stabilisers may be effective and relatively safe; however, this review finds that well-designed randomised controlled studies in the area is warranted.

Can Adverse Event Patterns Inform Shared Decision-Making in ADHD Treatment? A Systematic Review of Evidence From Registration Trials for FDA-Approved Treatments in Adults.

INTRODUCTION: Adult patients and clinicians are faced with several pharmacological options to manage attention-deficit/hyperactivity disorder (ADHD). If types or rates of adverse experiences vary among these options, these differences could inform the shared decision-making process. METHODS: To discern differentiating evidence-based patterns of risk, we analyzed data from FDA package labels for drugs approved to treat adult ADHD and reports from the registration trials used to create these labels. Three analyses of adverse effects were conducted: placebo-corrected occurrence at rates of 1 in 5, 10, and 20 participants, association with discontinuation, and uniqueness of occurrence within the treatment options. RESULTS: Among the 7 agents approved to treat adult ADHD, the number of types of side effects experienced during a mix of fixed and flexible-dose studies was greatest among the nonstimulant medications, but the stimulant medications had higher rates of occurrence of side effects. The minimum frequency at which all medications had adverse events was 1 in 10 participants. Overall discontinuation rates did not differ among the stimulant medications nor between stimulants and nonstimulants. DISCUSSION: To our knowledge, this is the first study to compile and compare data from all FDA registration trials for medications approved to treat adult ADHD. This article describes a process by which readily available adverse event reporting data can be used as a tool to inform shared clinical decision-making. While differences in the methodology and outcome reporting of the trials included may limit generalizability, the number of individual patients included and the completeness of the discontinuation data can be used to inform discussions with patients about the relative likelihood of adverse experiences and other patient concerns.

Proteomic Landscape Associated with Cognitive Impairment in Individuals with Long-term Methamphetamine Dependence.

BACKGROUND: Methamphetamine (METH) is a highly addictive drug that directly affects the central nervous system. METH use not only harms the user's health but also poses risks and costs to society. Prolonged METH dependence has been shown to impair cognition, which may be the primary factor in impulsive drug-seeking behaviors and high relapse rates. However, the molecular mechanisms underlying METH addiction and METH-induced cognitive decline remain poorly understood. METHODS: To illuminate the potential molecular mechanisms underpinning METH addiction, we compared serum protein expression levels between 12 long-term METH users and 12 healthy controls using label-free quantitative proteomics. Bioinformatic analyses were conducted to determine functional networks and protein-protein interactions. RESULTS: In total, 23 differentially expressed proteins were identified between the two groups. The differentially expressed proteins were related to cognitive dysfunction, neuroinflammation, immune impairment, metabolic disturbances, and calcium binding and regulation. CONCLUSIONS: These 23 proteins may underpin the multi-system damage induced by chronic METH exposure. Our findings provide novel insights into the molecular basis of METH addiction and inform potential prevention and treatment strategies for individuals with METH dependence.

Psychosis with use of amphetamine drugs, methylphenidate and atomoxetine in adolescent and adults.

BACKGROUND: Use of psychostimulants and relative drugs has increased worldwide in treatment of attention-deficit hyperactivity disorder (ADHD) in adolescents and adults. Recent studies suggest a potential association between use of psychostimulants and psychotic symptoms. The risk may not be the same between different psychostimulants. OBJECTIVE: To assess whether amphetamine or atomoxetine use is associated with a higher risk of reporting symptoms of psychosis than methylphenidate use in adolescents and adults, particularly in patients with ADHD. METHODS: Using VigiBase, the WHO's pharmacovigilance database, disproportionality of psychotic symptoms reporting was assessed among adverse drug reactions related to methylphenidate, atomoxetine and amphetamines, from January 2004 to December 2018, in patients aged 13-25 years. The association between psychotic symptoms and psychostimulants was estimated through the calculation of reporting OR (ROR). FINDINGS: Among 13 863 reports with at least one drug of interest, we found 221 cases of psychosis with methylphenidate use, 115 with atomoxetine use and 169 with a prescription of an amphetamine drug. Compared with methylphenidate use, amphetamine use was associated with an increased risk of reporting psychotic symptoms (ROR 1.61 (95% CI 1.26 to 2.06)]. When we restricted the analysis to ADHD indication, we found a close estimate (ROR 1.94 (95% CI 1.43 to 2.64)). No association was found for atomoxetine. CONCLUSION: Our study suggests that amphetamine use is associated with a higher reporting of psychotic symptoms, compared with methylphenidate use. CLINICAL IMPLICATIONS: The prescription of psychostimulants should consider this potential adverse effect when assessing the benefit-risk balance.

Costs associated with adverse events during treatment episodes for adult attention-deficit/hyperactivity disorder.

OBJECTIVE: Attention-deficit/hyperactivity disorder (ADHD) medication is frequently associated with adverse events (AEs), but limited real-world data exist regarding their costs from a payer's perspective. Therefore, this study evaluated the healthcare costs associated with common AEs among adult patients treated for ADHD in the US. METHODS: Eligible adults treated for ADHD were identified from a large US claims database (1 October 2015-30 September 2021). A retrospective cohort study design was used to assess excess healthcare costs and costs directly related to AE-specific claims per-patient-per-month (PPPM) associated with 10 selected AEs during ADHD treatment. To account for all costs associated with the AE, treatment episodes with a given AE were compared to similar treatment episodes without this AE. Entropy balancing was used to create cohorts with similar characteristics. Studied AEs were selected based on their prevalence in clinical trials for common ADHD medications and were identified from ICD-10-CM diagnosis codes recorded in claims. RESULTS: Among the 461,464 patients included (mean age: 34.2 years; 45.5% males), 49.4% had ≥1 AE during their treatment episode. Treatment episodes with AEs were associated with statistically significant AE-specific medical costs (erectile dysfunction: $57; fatigue: $82; dry mouth: $90; diarrhea: $162; insomnia: $147; anxiety: $281; nausea: $299; constipation: $356; urinary hesitation: $491; feeling jittery: $723) and excess healthcare costs PPPM (erectile dysfunction: $120, fatigue: $248, insomnia: $265, anxiety: $380, diarrhea: $441, dry mouth: $485, nausea: $709, constipation: $802, urinary hesitation: $1,105, feeling jittery: $1,160; p < .05). LIMITATIONS: AEs were identified based on recorded diagnosis on medical claims and likely represent more severe AEs. Therefore, costs may not be representative of milder AEs. CONCLUSIONS: This study found that AEs occurring during ADHD treatment episodes are associated with significant healthcare costs. This highlights the potential of treatments with favorable safety profiles to alleviate the burden experienced by patients and the healthcare system.

Efficacy and safety of established and off-label ADHD drug therapies for cognitive impairment or attention-deficit hyperactivity disorder symptoms in bipolar disorder: A systematic review by the ISBD Targeting Cognition Task Force.

BACKGROUND: Abnormalities in dopamine and norepinephrine signaling are implicated in cognitive impairments in bipolar disorder (BD) and attention-deficit hyperactivity disorder (ADHD). This systematic review by the ISBD Targeting Cognition Task Force therefore aimed to investigate the possible benefits on cognition and/or ADHD symptoms and safety of established and off-label ADHD therapies in BD. METHODS: We included studies of ADHD medications in BD patients, which involved cognitive and/or safety measures. We followed the procedures of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 statement. Searches were conducted on PubMed, Embase and PsycINFO from inception until June 2023. Two authors reviewed the studies independently using the Revised Cochrane Collaboration's Risk of Bias tool for Randomized trials. RESULTS: Seventeen studies were identified (N = 2136), investigating armodafinil (k = 4, N = 1581), methylphenidate (k = 4, N = 84), bupropion (k = 4, n = 249), clonidine (k = 1, n = 70), lisdexamphetamine (k = 1, n = 25), mixed amphetamine salts (k = 1, n = 30), or modafinil (k = 2, n = 97). Three studies investigated cognition, four ADHD symptoms, and 10 the safety. Three studies found treatment-related ADHD symptom reduction: two involved methylphenidate and one amphetamine salts. One study found a trend towards pro-cognitive effects of modafinil on some cognitive domains. No increased risk of (hypo)mania was observed. Five studies had low risk of bias, eleven a moderate risk, and one a serious risk of bias. CONCLUSIONS: Methylphenidate or mixed amphetamine salts may improve ADHD symptoms in BD. However, there is limited evidence regarding the effectiveness on cognition. The medications produced no increased mania risk when used alongside mood stabilizers. Further robust studies are needed to assess cognition in BD patients receiving psychostimulant treatment alongside mood stabilizers.

Effect of CYP2D6 genetic variation on patient-reported symptom improvement and side effects among children and adolescents treated with amphetamines.

OBJECTIVES: Amphetamine-based medications are recommended as a first-line pharmacotherapy for the treatment of attention-deficit/hyperactivity disorder in children and adolescents. However, the efficacy and tolerability of these medications vary across individuals, which could be related to interindividual differences in amphetamine metabolism. This study examined if genotype-predicted phenotypes of the cytochrome P450 isozyme CYP2D6 were associated with self-reported side effects and symptom improvement in youth treated with amphetamines. METHODS: Two hundred fourteen participants aged 6-24 who had a history of past or current amphetamine treatment were enrolled from Western Canada. Amphetamine dose and duration information was collected from the participants along with questions regarding adherence, concomitant medications, symptom improvement and side effects. DNA was extracted from saliva samples and genotyped for CYP2D6 . Binomial logistic regression models were used to determine the effect of CYP2D6 metabolizer phenotype with and without correction for phenoconversion on self-reported symptom improvement and side effects. RESULTS: Genotype-predicted CYP2D6 poor metabolizers had significantly higher odds of reporting symptom improvement when compared to intermediate metabolizers (OR = 3.67, 95% CI = 1.15-11.7, P  = 0.029) after correction for phenoconversion and adjusting for sex, age, dose, duration, and adherence. There was no association between CYP2D6 metabolizer phenotype and self-reported side effects. CONCLUSION: Our findings indicate that phenoconverted and genotype-predicted CYP2D6 poor metabolizer phenotype is significantly associated with higher odds of symptom improvement in children and adolescents treated with amphetamine. If replicated, these results could inform the development of future dosing guidelines for amphetamine treatment in children and adolescents.

Modeling methamphetamine use disorder in mammals: Sex differences in behavioral, biochemical, and transcriptional consequences.

Methamphetamine (METH) is the most commonly misused amphetamine-type stimulant throughout the globe. METH is very rewarding, and its misuse can lead to a diagnosis of METH use disorder (MUD). Although METH use is observed in both sexes, there are, however, reported differences in the clinical manifestations of METH use and its consequences. These observations indicate the need for more research on the long-term sex-dependent consequences of METH taking in both preclinical and clinical settings. In effect, sex is a biological variable that can impact conclusions drawn from various basic and clinical studies. Thus, the present chapter provides a succinct review of the current state of the research on METH and its sex-associated consequences. In addition to behavioral and cognitive aspects of METH use, we discuss METH-induced changes in neurotransmitter systems and structures in the brain. Thus, the book chapter serves to highlight the significance of sex as a critical element that needs to be considered during discussions of novel therapeutic approaches to MUD.

The pharmacology and neurotoxicology of synthetic cathinones.

The synthetic cathinones are man-made compounds derived from the naturally occurring drug cathinone, which is found in the khat plant. The drugs in this pharmacological class that will be the focus of this chapter include mephedrone, MDPV, methcathinone and methylone. These drugs are colloquially known as "bath salts". This misnomer suggests that these drugs are used for health improvement or that they have legitimate medical uses. The synthetic cathinones are dangerous drugs with powerful pharmacological effects that include high abuse potential, hyperthermia and hyperlocomotion. These drugs also share many of the pharmacological effects of the amphetamine class of drugs including methamphetamine, amphetamine and MDMA and therefore have high potential to cause damage to the central nervous system. The synthetic cathinones are frequently taken in combination with other psychoactive drugs such as alcohol, marijuana and the amphetamine-like stimulants, creating a situation where heightened pharmacological and neurotoxicological effects are likely to occur. Despite the structural features shared by the synthetic cathinones and amphetamine-like stimulants, including their actions at monoamine transporters and receptors, the effects of the synthetic cathinones do not always match those of the amphetamines. In particular, the synthetic cathinones are far less neurotoxic than their amphetamine counterparts, they produce a weaker hyperthermia, and they cause less glial activation. This chapter will briefly review the pharmacology and neurotoxicology of selected synthetic cathinones with the aim of delineating key areas of agreement and disagreement in the literature particularly as it relates to neurotoxicological outcomes.

Positive and negative symptoms in methamphetamine-induced psychosis compared to schizophrenia: A systematic review and meta-analysis.

BACKGROUND: The clinical profiles of methamphetamine-induced psychosis (MIP) and schizophrenia are largely overlapping making differentiation challenging. In this systematic review and meta-analysis, we aim to compare the positive and negative symptoms of MIP and schizophrenia to better understand the differences between them. STUDY DESIGN: In accordance with our pre-registered protocol (CRD42021286619), we conducted a search of English-language studies up to December 16th, 2022, in PubMed, EMBASE, and PsycINFO, including stable outpatients with MIP and schizophrenia. We used the Newcastle-Ottawa Scale to measure the quality of cross-sectional, case-control, and cohort studies. STUDY RESULTS: Of the 2052 articles retrieved, we included 12 studies (6 cross-sectional, 3 case-control, and 2 cohort studies) in our meta-analysis, involving 624 individuals with MIP and 524 individuals with schizophrenia. Our analysis found no significant difference in positive symptoms between the two groups (SMD, -0.01; 95%CI, -0.13 to +0.11; p = 1). However, individuals with MIP showed significantly less negative symptoms compared to those with schizophrenia (SMD, -0.35; 95CI%, -0.54 to -0.16; p = 0.01; I2 = 54 %). Our sensitivity analysis, which included only studies with a low risk of bias, did not change the results. However, our meta-analysis is limited by its cross-sectional approach, which limits the interpretation of causal associations. Furthermore, differences in population, inclusion criteria, methodology, and drug exposure impact our findings. CONCLUSIONS: Negative symptoms are less prominent in individuals with MIP. While both groups do not differ regarding positive symptoms, raises the possibility of shared and partly different underlying neurobiological mechanisms related to MIP and schizophrenia.

Suicide, Stimulants, and Selective Serotonin Reuptake Inhibitors: A Retrospective Chart Review.

Background: Previous studies suggest that selective serotonin reuptake inhibitors (SSRIs) may increase the risk of suicide among children and youth, although the association between suicide risk and the combination of SSRIs with other medication such as stimulants in this population remains unclear. This study explored whether the combination of SSRIs with stimulants influenced suicide risk. Methods: A retrospective cohort study was conducted at a single children's hospital campus-based ambulatory psychiatric clinic between September 1, 2017, and September 30, 2020. Subjects were 6-21 years of age and prescribed either stimulants or stimulants and SSRIs only. The primary outcome was suicidal thoughts and behaviors (STB), defined by documented suicidal thoughts, plans, or behaviors. Firth logistic regression evaluated associations between medication class and STB. Results: Among 349 patients, the prevalence of STB was 5.7% (n = 20). In unadjusted model, patients prescribed SSRIs and stimulants had a 2.9-fold increase of STB compared to patients prescribed stimulants only, along with increasing age, male sex, and the diagnoses of anxiety and/or depression. In the final model adjusted for each of these factors, the observed association of medication regiment with STB was attenuated (odds ratio [OR]: 1.3, confidence interval [CI]: 0.3-4.9, p = 0.7). The magnitude of the adjusted association between depressive diagnosis and STB was notable (OR: 3.6, CI: 1.0-12.6, p = 0.049). Conclusions: Among patients followed in a children's hospital-based ambulatory psychiatric clinic, a combination medication regimen of SSRIs and stimulants after adjusting for genetic sex, age, anxiety diagnosis, and depression diagnosis, the observed association between STB and combination stimulant and SSRI treatment was attenuated. This finding suggests that other factors, including depression, may have contributed to the association between SSRI treatment and STB. Larger, prospective studies of the relationship between combination pharmacotherapy and suicide risk are warranted to guide clinical/pharmacological decision making and to better clarify these relationships.

The Impact of Methylphenidate on Pubertal Maturation and Bone Age in ADHD Children and Adolescents: Results from the ADHD Drugs Use Chronic Effects (ADDUCE) Project.

OBJECTIVE: The short-term safety of methylphenidate (MPH) has been widely demonstrated; however the long-term safety is less clear. The aim of this study was to investigate the safety of MPH in relation to pubertal maturation and to explore the monitoring of bone age. METHOD: Participants from ADDUCE, a two-year observational longitudinal study with three parallel cohorts (MPH group, no-MPH group, and a non-ADHD control group), were compared with respect to Tanner staging. An Italian subsample of medicated-ADHD was further assessed by the monitoring of bone age. RESULTS: The medicated and unmedicated ADHD groups did not differ in Tanner stages indicating no higher risk of sexual maturational delay in the MPH-treated patients. The medicated subsample monitored for bone age showed a slight acceleration of the bone maturation after 24 months, however their predicted adult height remained stable. CONCLUSION: Our results do not suggest safety concerns on long-term treatment with MPH in relation to pubertal maturation and growth.

Neuronal activation of nucleus accumbens by local methamphetamine administration induces cognitive impairment through microglial inflammation in mice.

More than half of methamphetamine (METH) users present with cognitive impairment, making it difficult for them to reintegrate into society. However, the mechanisms of METH-induced cognitive impairment remain unclear. METH causes neuronal hyperactivation in the nucleus accumbens (NAc) by aberrantly releasing dopamine, which triggers dependence. In this study, to clarify the involvement of hyperactivation of NAc in METH-induced cognitive impairment, mice were locally microinjected with METH into NAc (mice with METH (NAc)) and investigated their cognitive phenotype. Mice with METH (NAc) exhibited cognitive dysfunction in behavioral analyses and decreased long-term potentiation in the hippocampus, with NAc activation confirmed by expression of FosB, a neuronal activity marker. In the hippocampus of mice with METH (NAc), activated microglia, but not astroglia, and upregulated microglia-related genes, Il1b and C1qa were observed. Finally, administration of minocycline, a tetracycline antibiotic with suppressive effect on microglial activation, to mice with METH (NAc) ameliorated cognitive impairment and synaptic dysfunction by suppressing the increased expression of Il1b and C1qa in the hippocampus. In conclusion, activation of NAc by injection of METH into NAc elicited cognitive impairment by facilitating immune activation in mice. This study suggests that immunological intervention could be a therapeutic strategy for addiction-related cognitive disturbances.

ADHD medications use and risk of mortality and unintentional injuries: a population-based cohort study.

We assessed the association between the use of medications for attention-deficit/hyperactivity disorder (ADHD) and the risk of all-cause mortality and unintentional injuries leading to emergency department (ED) or hospital admission in individuals aged ≤24 years with ADHD. We conducted a population-based retrospective cohort study between 2000 and 2021 using Quebec health administrative data. Individuals were followed from the first ADHD diagnosis or ADHD medication claim until turning 25, death, or study end. Exposure was defined as mutually exclusive episodes of ADHD medication use and/or coverage under the public provincial drug plan (PDP): 1) covered and not treated with ADHD medication; 2) covered and treated with ADHD medication; and 3) not covered under the PDP. The risk of all-cause mortality and unintentional injuries associated with exposure episodes was estimated using multivariable survival analyses. The cohort included n = 217 192 individuals aged 1-24 years with a male to female ratio of close to 2:1. Compared to non-medication use, episodes of ADHD medication use, overall, were associated with reduced all-cause mortality (adjusted hazard ratio, aHR 0.61, 95% CI 0.48-0.76) and unintentional injury leading to ED (0.75, 0.74-0.77) or hospitalisation (0.71, 0.68-0.75). Episodes of stimulants were associated with a lower risk of all-cause mortality and reduced risk of unintentional injuries, while episodes with non-stimulants and with both stimulants and non-stimulants concomitantly were associated with reduced risk of unintentional injuries, but not of all-cause mortality. Although residual confounding cannot be excluded, stimulants may have a protective effect in terms of risk of all-cause mortality and both stimulants and non-stimulants for ADHD may reduce the risk of unintentional injuries. The findings of the current study should inform clinical decision making on the choice of starting a pharmacological treatment for ADHD, when a balance needs to be struck between expected benefits and possible risks.

Assessment of lisdexamfetamine on executive function in rats: A translational cognitive research.

Executive function, including working memory, attention and inhibitory control, is crucial for decision making, thinking and planning. Lisdexamfetamine, the prodrug of d-amphetamine, has been approved for treating attention-deficit hyperactivity disorder and binge eating disorder, but whether it improves executive function under non-disease condition, as well as the underlying pharmacokinetic and neurochemical properties, remains unclear. Here, using trial unique non-matching to location task and five-choice serial reaction time task of rats, we found lisdexamfetamine (p.o) enhanced spatial working memory and sustained attention under various cognitive load conditions, while d-amphetamine (i.p) only improved these cognitive performances under certain high cognitive load condition. Additionally, lisdexamfetamine evoked less impulsivity than d-amphetamine, indicating lower adverse effect on inhibitory control. In vivo pharmacokinetics showed lisdexamfetamine produced a relative stable and lasting release of amphetamine base both in plasma and in brain tissue, whereas d-amphetamine injection elicited rapid increase and dramatical decrease in amphetamine base levels. Microdialysis revealed lisdexamfetamine caused lasting release of dopamine within the medial prefrontal cortex (mPFC), whereas d-amphetamine produced rapid increase followed by decline to dopamine level. Moreover, lisdexamfetamine elicited more obvious efflux of noradrenaline than that of d-amphetamine. The distinct neurochemical profiles may be partly attributed to the different action of two drugs to membranous catecholamine transporters level within mPFC, detecting by Western Blotting. Taken together, due to its certain pharmacokinetic and catecholamine releasing profiles, lisdexamfetamine produced better pharmacological action to improving executive function. Our finding provided valuable evidence on the ideal pharmacokinetic and neurochemical characteristics of amphetamine-type psychostimulants in cognition enhancement.