The Efficacy of Psychostimulants in Major Depressive Episodes: A Systematic Review and Meta-Analysis

Prescribed psychostimulants and other pro-cognitive medications in bipolar disorder: A systematic review and meta-analysis of recurrence of manic symptoms

OBJECTIVES

Clinicians are often hesitant to prescribe psychostimulants in bipolar disorder (BD) due to concerns of inducing (hypo)mania, despite limited published evidence on associations between prescribed psychostimulant use and recurrence of mood episodes in BD. The current systematic review and meta-analysis evaluated the emergence of (hypo)manic symptoms in patients with BD receiving prescribed psychostimulants or other pro-cognitive medications in euthymic or depressive states.

METHODS

A systematic search was performed of MEDLINE, Embase, and PsychINFO from inception to April 5, 2023 and search of Clinicaltrials.gov and Clinicaltrialsregister.eu for unpublished data. References of included studies were hand-searched. Randomized trials and prospective longitudinal studies that evaluated psychostimulants and non-stimulant medications recommended for the treatment of ADHD by the Canadian ADHD practice guidelines were included. The review was reported in line with PRISMA guidelines and was preregistered on PROSPERO (CRD42022358588).

RESULTS

After screening 414 unique records, we included 27 studies, of which five reported data that was quantitatively synthesized (n = 1653). The use of psychostimulants in BD was not associated with increased scores on the Young Mania Rating Scale in patients who were in a euthymic or depressed state (SMD IV -0.17; 95% CI, -0.40 to 0.06) compared to placebo. There was a high degree of study-level heterogeneity (I2 = 80%). A qualitative synthesis of studies revealed a limited risk of medication-induced manic symptoms.

CONCLUSIONS

Our review provides preliminary evidence to suggest psychostimulants and non-stimulant ADHD medications have a limited risk of precipitating (hypo)mania symptoms. More extensive studies evaluating the safety and efficacy of these medications are warranted.

Adjunctive cariprazine as a novel effective strategy for treating major depressive disorder: A systematic review and meta-analysis

BACKGROUND

Cariprazine has been approved by the Food and Drug Administration for treating bipolar depression and as an adjunctive treatment for Major Depressive Disorder (MDD). However, it remains unclear about its pharmacological efficacy in treating MDD. Therefore, a meta-analysis was conducted to investigate the adjunctive use of cariprazine in MDD.

METHODS

Electronic databases were searched for eligible studies evaluating the efficacy and safety of cariprazine in patients with MDD up to November 15, 2023. The changes in Montgomery-Asberg Depression Rating Scale (MADRS) score and incidence of adverse events (AEs), which represents of efficacy and tolerability, are considered as the main outcomes.

RESULTS

A total of 3066 patients with MDD included in all across 5 RCTs. With regard to MADRS score, cariprazine group showed better results than control group (SMD = -0.12, 95% CI -0.19 to -0.04, P = 0.002, 5 RCTs, n = 3066). Cariprazine, meanwhile, improved the MADRS response (RR = 1.19, 95% CI 1.08 to 1.31, P = 0.0004, 5 RCTs, n = 3066). For safety outcomes, statistical difference was observed in AEs (RR = 1.26, 95% CI 1.18 to 1.35, P < 0.00001, 5 RCTs, n = 3077). The suicide ideation and SAEs showed no statistical difference between two groups.

CONCLUSION

Cariprazine demonstrated antidepressant effect as an augmentation therapy in treating MDD. Meanwhile, the tolerability of it was acceptable as an adjunctive treatment. However, studies with larger sample sizes are still needed to explore the optimal dosage.

Lack of effect of methamphetamine on reward-related brain activity in healthy adults

INTRODUCTION

Stimulant drugs are thought to alter processing of rewarding stimuli. However, the mechanisms by which they do this are not fully understood.

METHOD

In this study we used EEG to assess effects of single doses of methamphetamine (MA) on neural responses during anticipation and receipt of reward in healthy volunteers. Healthy young men and women (N = 28) completed three sessions in which they received placebo, a low MA dose (10 mg) or a higher MA dose (20 mg) under double blind conditions. Subjective and cardiovascular measures were obtained, and EEG was used to assess brain activity during an electrophysiological version of the Monetary Incentive Delay (eMID) task.

RESULTS

EEG measures showed expected patterns during anticipation and receipt of reward, and MA produced its expected effects on mood and cardiovascular function. However, MA did not affect EEG responses during either anticipation or receipt of rewards.

CONCLUSIONS

These findings suggest that the effects of MA on EEG signals of reward processing are subtle, and not related to the drug's effects on subjective feelings of well-being. The findings contribute to our understanding of the neural effects of MA during behaviors related to reward.

Treatment-resistant depression in children and adolescents

Major depressive disorder (MDD) in children and adolescents is a significant health problem, causing profound impairments in social, academic, and family functioning and substantial morbidity and mortality. Up to 15% of children and adolescents suffer from MDD, and a proportion, around 30 to 40% of them, failed to respond to initial selective serotonin reuptake inhibitor (SSRI) treatment. The only evidence-based recommendation is medication switching to another SSRI and augmentation with cognitive behavioral therapy. Newly developing treatment, including ketamine, transcranial magnetic stimulation, psychotherapy other than cognitive behavioral therapy, and combined pharmacotherapy with other interventions, requires further longitudinal controlled trials regarding efficacy and safety in this vulnerable population.

Risk of Major Malformations in Infants After First-Trimester Exposure to Stimulants: Results From the Massachusetts General Hospital National Pregnancy Registry for Psychiatric Medications

PURPOSE/BACKGROUND

The prevalence of attention-deficit/hyperactivity disorder in adult females is 3% to 4%. Attention-deficit/hyperactivity disorder is highly comorbid with other psychiatric disorders such as mood, anxiety, and substance use disorders. For reproductive-aged women, the treatment of attention-deficit/hyperactivity disorder with stimulant medications may be considered during pregnancy or breastfeeding, although historically, data are lacking to inform these decisions. The aim of this investigation was to determine the risk of major malformations in infants after first-trimester prescription stimulant exposure in a small but rigorously characterized sample.

METHODS/PROCEDURES

The Massachusetts General Hospital National Pregnancy Registry for Psychiatric Medications systematically ascertains information from pregnant females including demographic information, medical and psychiatric history, use of prescription medications, and other information relevant to fetal outcomes. Participants provide verbal informed consent and are interviewed twice during gestation and again at approximately 3 months postpartum. The primary outcome of interest is the presence of a major malformation identified within 6 months after birth. Redacted cases of major malformations are reviewed by a dysmorphologist blinded to medication exposure.

FINDINGS/RESULTS

A total of N = 1988 women were eligible for this analysis, including the following exposures: n = 173 to mixed amphetamine salts; n = 40 to lisdexamfetamine; n = 45 to methylphenidate; n = 3 to dexmethylphenidate; and n = 1755 controls. The odds ratio of a major malformation among infants after first-trimester exposure to any stimulant was 0.39 (95% confidence interval, 0.09-1.61) compared with controls. There were no major malformations observed in infants exposed to lisdexamfetamine, methylphenidate, or dexmethylphenidate.

IMPLICATIONS/CONCLUSIONS

Although preliminary, this analysis from an ongoing pregnancy registry provides reassurance that these stimulants do not appear to have major teratogenic effects.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01246765.

Impulsivity in Depression: Its Relation to Suicidality

OBJECTIVE

Impulsivity is an important risk for suicidality, which is common in patients with major depressive disorder (MDD). The goal of this study was to examine multiple facets of impulsivity in depressed patients compared with healthy controls and to assess their relationship to suicidality.

METHOD

Outpatients diagnosed with MDD using the Structured Clinical Interview for DSM-IV were recruited. Two groups were constituted as "MDD in remission" (n=32) and "MDD" (n=71). The "healthy control" group (n=30) consisted of individuals who had never been diagnosed with any psychiatric disorder. Impulsivity was assessed with the Barratt Impulsivity Scale (BIS), a self-rating measure, and with the following behavioral tasks: Go/No-go Task, Iowa Gambling Task, and Balloon Analogue Risk Task. The scores of the 3 groups (n=133) were compared to evaluate the effect of MDD. The scores were also analyzed and compared in the patients in the 2 MDD groups (n=103) with respect to their current and lifetime suicidality.

RESULTS

There was no difference in the 3 groups in task scores, but nonplanning BIS was correlated with the severity of depressive symptoms. Patients with suicidal ideation (SI) had higher BIS total and attention impulsivity scores and more commission errors on the Go/No-go Task, reflecting failure in response inhibition, compared with the patients without SI.

CONCLUSIONS

Failure to show differences in impulsivity-related tasks suggests that there might be no relationship between the state of depression and impulsivity. However, these findings confirm that there is an association between SI and response inhibition and the attention facet of impulsivity in depression.

Psychostimulants as antidepressants: Their nuanced role?

While effectively the 'first antidepressants', the psychostimulants are rarely prescribed as antidepressant drugs seemingly in light of their judged low effectiveness, side effects, tolerance as well as concerns about dependency and abuse. Recent meta-analyses do find some support for them as being effective antidepressants for those with major depression, but they have not been closely evaluated in terms of their specific nuanced role for treating treatment-resistant (unipolar and bipolar) melancholic depression. The author has so prescribed them for over a decade and offers a case for their benefits for a distinct percentage of those with such conditions and notes their relatively few side effects.

Augmentation strategies for treatment resistant major depression: A systematic review and network meta-analysis

OBJECTIVE

To compare the efficacy and discontinuation of augmentation agents in adult patients with treatment-resistant depression (TRD). We conducted a systematic review and network meta-analyses (NMA) to combine direct and indirect comparisons of augmentation agents.

METHODS

We included randomized controlled trials comparing one active drug with another or with placebo following a treatment course up to 24 weeks. Nineteen agents were included: stimulants, atypical antipsychotics, thyroid hormones, antidepressants, and mood stabilizers. Data for response/remission and all-cause discontinuation rates were analyzed. We estimated effect-size by relative risk using pairwise and NMA with random-effects model.

RESULTS

A total of 65 studies (N = 12,415) with 19 augmentation agents were included in the NMA. Our findings from the NMA for response rates, compared to placebo, were significant for: liothyronine, nortriptyline, aripiprazole, brexpiprazole, quetiapine, lithium, modafinil, olanzapine (fluoxetine), cariprazine, and lisdexamfetamine. For remission rates, compared to placebo, were significant for: thyroid hormone(T4), aripiprazole, brexpiprazole, risperidone, quetiapine, and olanzapine (fluoxetine). Compared to placebo, ziprasidone, mirtazapine, and cariprazine had statistically significant higher discontinuation rates. Overall, 24% studies were rated as having low risk of bias (RoB), 63% had moderate RoB and 13% had high RoB.

LIMITATIONS

Heterogeneity in TRD definitions, variable trial duration and methodological clinical design of older studies and small number of trials per comparisons.

CONCLUSIONS

This NMA suggests a superiority of the regulatory approved adjunctive atypical antipsychotics, thyroid hormones, dopamine compounds (modafinil and lisdexamfetamine) and lithium. Acceptability was lower with ziprasidone, mirtazapine, and cariprazine. Further research and head-to-head studies should be considered to strengthen the best available options for TRD.

Stimulant use for self-management of pain among safety-net patients with chronic non-cancer pain

BACKGROUND

Chronic pain affects one-fifth of US adults. Reductions in opioid prescribing have been associated with increased non-prescription opioid use and, chronologically, increased stimulant (methamphetamine and cocaine) use. While non-prescription opioid use is commonly attributed to pain self-management, the role of stimulants in managing pain is unclear.

METHODS

We analyzed baseline data from a longitudinal study of patients with chronic non-cancer pain in an urban safety-net healthcare system who had been prescribed an opioid for ≥3 of the last 12 months, and had a history of non-prescription opioid, cocaine, or amphetamine use (N = 300). We estimated the prevalence and identified correlates of stimulant use to treat pain among a subgroup of patients who reported past-year stimulant use (N = 105). Data sources included computer-assisted questionnaire (demographics, substance use, pain), clinical exam and procedures (pain, pain tolerance), and chart abstraction (opioid prescriptions). We conducted bivariate analyses to assess associations between demographics, pain characteristics, non-opioid therapies, substance use, opioid prescriptions, and self-reported symptoms, with reporting using stimulants to treat pain. Demographic variables and those with significant bivariate associations were included in a multivariable logistic regression model.

RESULTS

Fifty-two percent of participants with past-year stimulant use reported using stimulants in the past year to treat pain. Participants who used stimulants for pain reported slightly higher average pain in the past 3 months (median of 8 (IQR: 6-8) vs 7 (7-9) out of 10, p = 0.049). In the multivariable analysis, female gender (AOR= 3.20, 95% CI: 1.06-9.63, p = 0.039) and higher score on the Douleur Neuropathique 4 neuropathic pain questionnaire (AOR = 1.34, 95% CI: 1.05-1.70, p = 0.017) were associated with past-year stimulant use to treat pain.

CONCLUSION

Stimulants may be used for pain self-management, particularly for neuropathic pain and among women. Our findings suggest an underexplored motivation for stimulant use in an era of reduced access to prescribed opioids.

Probabilistic Reinforcement Learning and Anhedonia

Despite the prominence of anhedonic symptoms associated with diverse neuropsychiatric conditions, there are currently no approved therapeutics designed to attenuate the loss of responsivity to previously rewarding stimuli. However, the search for improved treatment options for anhedonia has been reinvigorated by a recent reconceptualization of the very construct of anhedonia, including within the Research Domain Criteria (RDoC) initiative. This chapter will focus on the RDoC Positive Valence Systems construct of reward learning generally and sub-construct of probabilistic reinforcement learning specifically. The general framework emphasizes objective measurement of a subject's responsivity to reward via reinforcement learning under asymmetrical probabilistic contingencies as a means to quantify reward learning. Indeed, blunted reward responsiveness and reward learning are central features of anhedonia and have been repeatedly described in major depression. Moreover, these probabilistic reinforcement techniques can also reveal neurobiological mechanisms to aid development of innovative treatment approaches. In this chapter, we describe how investigating reward learning can improve our understanding of anhedonia via the four RDoC-recommended tasks that have been used to probe sensitivity to probabilistic reinforcement contingencies and how such task performance is disrupted in various neuropsychiatric conditions. We also illustrate how reverse translational approaches of probabilistic reinforcement assays in laboratory animals can inform understanding of pharmacological and physiological mechanisms. Next, we briefly summarize the neurobiology of probabilistic reinforcement learning, with a focus on the prefrontal cortex, anterior cingulate cortex, striatum, and amygdala. Finally, we discuss treatment implications and future directions in this burgeoning area.

Key considerations in the pharmacological management of treatment-resistant depression

Introduction: Treatment-resistant depression (TRD) is a complex, multifactorial, and biologically heterogeneous disorder with debilitating outcomes. Understanding individual reasons why patients do not respond to treatment is necessary for improving clinical recommendations regarding medication regimens, augmentation strategies, and alternative treatments.Areas covered: This manuscript reviews evidence-based treatment strategies for the clinical management of TRD. Current developments in the field and potential future recommendations for personalized treatment of TRD are also discussed.Expert opinion: Treatment guidelines for TRD are limited by the heterogeneous nature of the disorder. Furthermore, current strategies reflect this heterogeneity by emphasizing disease characteristics as well as drug trial response or failure. Developing robust biomarkers that could one day be integrated into clinical practice has the potential to advance specific treatment targets and ultimately improve treatment and remission outcomes.

Examining the effects of psychoactive drugs on complex behavioral processes in laboratory animals

Behavioral pharmacology has been aided significantly by the development of innovative cognitive tasks designed to examine complex behavioral processes in laboratory animals. Performance outcomes under these conditions have provided key metrics of drug action which serve to supplement traditional in vivo assays of physiologic and behavioral effects of psychoactive drugs. This chapter provides a primer of cognitive tasks designed to assay different aspects of complex behavior, including learning, cognitive flexibility, memory, attention, motivation, and impulsivity. Both capstone studies and recent publications are highlighted throughout to illustrate task value for two distinct but often interconnected translational strategies. First, task performance in laboratory animals can be utilized to elucidate how drugs of abuse affect complex behavioral processes. Here, the expectation is that adverse effects on such processes will have predictive relevance to consequences that will be experienced by humans. Second, these same task outcomes can be used to evaluate candidate therapeutics. In this case, the extent to which drug doses with medicinal value perturb task performance can contribute critical information for a more complete safety profile appraisal and advance the process of medications development. Methodological and theoretical considerations are discussed and include an emphasis on determining selectivity in drug action on complex behavioral processes.

Comparative efficacy and safety of stimulant-type medications for depression: A systematic review and network meta-analysis

BACKGROUND

Globally, depression impacts nearly 300 million people, and roughly half do not achieve remission with standard first-line therapies. For such individuals, augmentation strategies are often helpful at reducing the severity of depression. While there are many potential adjunctive medication choices, psychostimulants are among the more controversial options.

OBJECTIVES

The present review sought to clarify the comparative efficacy and safety of different stimulant-like medications to treat depression.

METHODS

We conducted a systematic review and network meta-analysis of randomized, controlled trials (RCTs) using psychostimulant medications to treat adults with depression. Outcomes were pooled using rate ratios (RRs) for dichotomous outcomes (e.g., response, adverse events) and standardized mean differences (SMDs) for continuous outcomes (e.g., change in depression scores).

RESULTS

We identified 37 eligible studies (ranging from 1958 to 2016). We assessed nine psychostimulants: methylphenidate (n=14), dextroamphetamine (n=9), modafinil (n=6), lisdexamphetamine (n=3), methylamphetamine (n=3), pemoline (n=2), atomoxetine (n=1), desipramine (n=1), and imipramine (n=1). Overall, psychostimulants demonstrated efficacy for depression, reduced fatigue and sleepiness, and appeared well-tolerated. However, there was inconsistent evidence across particular psychostimulants. For example, the only psychostimulant which demonstrated efficacy for depression-in terms of both symptom severity and response rates-was methylphenidate.

CONCLUSIONS

While our review suggests that some psychostimulants-particularly methylphenidate-appear well-tolerated and demonstrate some efficacy for depression, as well as fatigue and sleepiness, the strength of evidence in our estimates was low to very low for most agents given the small sample sizes, few RCTs, and imprecision in most estimates. A lack of consistent evidence precludes a definitive hierarchy of treatments and points to a need for additional, high-quality RCTs.

Circadian rhythm sleep-wake disturbances and depression in young people: implications for prevention and early intervention

A rate-limiting step in the prevention and early intervention of depressive disorders in young people is our insufficient understanding of causal mechanisms. One plausible pathophysiological pathway is disturbance in the 24 h sleep-wake cycle and the underlying circadian system. Abnormalities in circadian rhythms are well documented in adults with various depressive disorders and have been linked to core clinical features, including unstable mood, daytime fatigue, non-restorative sleep, reduced motor activity, somatic symptoms, and appetite and weight change. In this Review, we summarise four areas of research: basic circadian biology and animal models of circadian disturbances; developmental changes in circadian rhythms during adolescence and implications for the emergence of adolescent-onset depressive syndromes; community and clinical studies linking 24 h sleep-wake cycle disturbances and depressive disorders; and clinical trials of circadian-based treatments. We present recommendations based on a highly personalised, early intervention model for circadian-linked depression in young people.

[Treatments for depression in consultation-liaison psychiatry: From theory to practice]

Treatments for depression include an adapted lifestyle, physical activity, psychotherapies, antidepressant and mood stabilizing drugs, neuromodulation, chronotherapy, spa treatments. Drug treatments used for major depressive episode are antidepressants and mood stabilizers. For a mild episode, psychotherapy is indicated. It should be combined with an antidepressant (serotonin reuptake inhibitor) for moderate and severe episodes. Suicide risk assessment is essential throughout the depressive episode. It is recommended to monitor at the start of antidepressant treatment for suicidal behavior, a change in mood suggesting an underlying bipolar disorder. The effectiveness of the treatment is evaluated after 4 to 8 weeks. The total duration of antidepressant treatment for an EDC is between 6 months and 1 year after remission, in order to prevent relapses. The use of liaison psychiatry, a real healthcare system within the general hospital, is strongly recommended for better screening and treatment of depression, thus reducing the length of hospital stays, improving the prognosis of depression. The aim of this article is to provide clinicians with a summary of validated data on the efficacy/tolerance of treatment for depression, and to suggest practical action to be taken on the main daily clinical situations: treating comorbid conditions, taking into account interactions drugs, manage the serotonin syndrome, lead to withdrawal from antidepressants, manage treatment in the elderly.

Circadian depression: A mood disorder phenotype

Major mood syndromes are among the most common and disabling mental disorders. However, a lack of clear delineation of their underlying pathophysiological mechanisms is a major barrier to prevention and optimised treatments. Dysfunction of the 24-h circadian system is a candidate mechanism that has genetic, behavioural, and neurobiological links to mood syndromes. Here, we outline evidence for a new clinical phenotype, which we have called 'circadian depression'. We propose that key clinical characteristics of circadian depression include disrupted 24-h sleep-wake cycles, reduced motor activity, low subjective energy, and weight gain. The illness course includes early age-of-onset, phenomena suggestive of bipolarity (defined by bidirectional associations between objective motor and subjective energy/mood states), poor response to conventional antidepressant medications, and concurrent cardiometabolic and inflammatory disturbances. Identifying this phenotype could be clinically valuable, as circadian-targeted strategies show promise for reducing depressive symptoms and stabilising illness course. Further investigation of underlying circadian disturbances in mood syndromes is needed to evaluate the clinical utility of this phenotype and guide the optimal use of circadian-targeted interventions.

The "VIP-ADHD trial": Does brain arousal have prognostic value for predicting response to psychostimulants in adult ADHD patients?

EEG studies have shown that adult ADHD patients have less stable brain arousal regulation than age and gender matched controls. Psychostimulants have brain arousal stabilising properties evident in EEG patterns. The aim of this study was to investigate whether the stability of brain arousal regulation has prognostic value in predicting response to methylphenidate therapy in adult ADHD patients. In an open-label, single-arm, multi-centre, confirmatory trial, 121 adult ADHD patients were recruited and 112 qualified for the full analysis set. All participants received an initial dose of 20 mg extended release methylphenidate at baseline. After a titration phase of up to 4 weeks, patients remained on a weight-based target dose of extended release methylphenidate for 4 weeks. Using the Vigilance Algorithm Leipzig (VIGALL 2.1), we assessed brain arousal regulation before the treatment with methylphenidate, based on a 15-min EEG at quiet rest recorded at baseline. Using automatic stage-classification of 1 s segments, we computed the mean EEG-vigilance (indexing arousal level) and an arousal stability score (indexing arousal regulation). The primary endpoint was the association between successful therapy, defined by a 30% reduction in CAARS, and stable/unstable brain arousal. 52 patients (46%) showed an unstable brain arousal regulation of which 23% had therapy success. In the stable group, 35% had therapy success, implying an absolute difference of 12 percentage points (95% CI -5 to 29, p = 0.17) in the direction opposite to the hypothesized one. There were no new findings regarding the tolerability and safety of extended release methylphenidate therapy.

Empirical validation of a touchscreen probabilistic reward task in rats

Anhedonia, the loss of pleasure from previously rewarding activities, is implicated in several neuropsychiatric conditions, including major depressive disorder (MDD). In order to accelerate drug development for mood disorders, quantitative approaches are needed to objectively measure responsiveness to reward as a means to identify deficits. One such approach, the probabilistic reward task (PRT), uses visual discrimination methodology to quantify reward learning. In this computerized task, humans make visual discriminations, and probabilistic contingencies are arranged such that correct responses to one alternative are rewarded more often (rich) than correct responses to the other (lean). Healthy participants consistently develop a response bias in favor of the rich alternative. However, participants with MDD typically exhibit lower response biases, and this blunting correlates with current and future anhedonia. The present studies validated a touchscreen-based PRT in rodents with formal and functional similarity to the human task. First, rats were trained to discriminate between two lines that differed in length. Next, parametric manipulations of probabilistic contingencies, line-length stimuli, and drug treatment (amphetamine, 0.32-3.2 mg/kg; scopolamine, 0.1-1.0 mg/kg; oxycodone, 0.1-1.0 mg/kg) on response bias were evaluated. Results demonstrated orderly shifts in bias and discriminability that varied as a function of, respectively, the asymmetry of rich/lean probabilities and disparity in line lengths. Drugs that enhance reward responsiveness (amphetamine and scopolamine, but not oxycodone) increased bias, verifying pharmacological task sensitivity. Finally, performance outcomes under optimized conditions were replicated in female rats. Collectively, the touchscreen-based rodent PRT appears to have high preclinical value as a quantitative assay of reward learning.

Some Reasons Why Preclinical Studies of Psychiatric Disorders Fail to Translate: What Can Be Rescued from the Misunderstanding and Misuse of Animal 'Models'?

The repeated failure of animal models to yield findings that translate into humans is a serious threat to the credibility of preclinical biomedical research. The use of animals in research that lacks translational validity is unacceptable in any ethical environment, and so this problem needs urgent attention. To reproduce any human illness in animals is a serious challenge, but this is especially the case for psychiatric disorders. Yet, many authors do not hesitate to describe their findings as a 'model' of such a disorder. More cautious scientists describe the behavioural phenotype as 'disorder-like', without specifying the way(s) in which the abnormal behaviour could be regarded as being analogous to any of the diagnostic features of the disorder in question. By way of discussing these problems, this article focuses on common, but flawed, assumptions that pervade preclinical research of depression and antidepressants. Particular attention is given to the difference between putative 'models' of this illness and predictive screens for candidate drug treatments, which is evidently widely misunderstood. However, the problems highlighted in this article are generic and afflict research of all psychiatric disorders. This dire situation will be resolved only when funders and journal editors take action to ensure that researchers interpret their findings in a less ambitious, but more realistic, evidence-based way that would parallel changes in research of the cause(s), diagnosis and treatment of psychiatric problems in humans.

The use of stimulants in depression: Results from a self-controlled register study

OBJECTIVE

To investigate the effectiveness of stimulants in patients with depression, by using naturalistic outcome measures, such as psychiatric admissions, psychiatric bed-days and incidents of intentional self-harm or suicide attempts.

METHODS

Via linkage of the Danish nationwide health registers, we identified all patients with a diagnosis of depression initiating stimulants, including methylphenidate, modafinil, amphetamine, dexamphetamine or lisdexamphetamine, from 1995 to 2012. We used a mirror-image model to test whether redemption of a stimulant prescription was associated with a reduction in psychiatric admissions, inpatient days and incidents of intentional self-harm or suicide attempts. Specifically, the number of these outcomes in the 2 years leading up to redemption of a stimulant prescription was compared to the two subsequent years. Similar outcomes were used in a reverse mirror-image model to investigate the effect of stimulant termination.

RESULTS

A total of 3354, 935 and 105 patients diagnosed with depression redeemed prescriptions for methylphenidate, modafinil or amphetamine/dexamphetamine/lisdexamphetamine, respectively. Initiation of methylphenidate was not associated with a significant change in psychiatric admissions (mean: -0.02 admissions, p = 0.11) or inpatient days (mean: 0.13 days, p = 0.74). Similar findings were made for modafinil and the amphetamines. In addition, no clinically relevant change in psychiatric admissions or inpatient days was found after termination of a stimulant. After initiation of methylphenidate, the incidents of self-harm or suicide attempts were reduced by 54%, from 68 to 31 events (p = 0.004). No significant change in incidents of self-harm or suicide attempts were found for modafinil or the amphetamines.

CONCLUSION

This nationwide study, using naturalistic outcomes, does not support the use of stimulants in patients with depression. However, the use of methylphenidate was associated with a 54% reduction in incidents of self-harm or suicide attempts, indicating that methylphenidate may potentially be useful in patients with depression with suicidal- or self-harming behaviour. However, further studies are needed, before any firm conclusions can be made.

C-reactive protein and clinical subtypes of major depressive disorder at Zagazig University Hospitals

Background

Although, the relation between inflammation and major depressive disorder (MDD) looks like firm, it may not exist in all patients with depression. Therefore, the main aim of this study was to compare serum C-reactive protein (CRP) level among clinical subtypes of MDD and its relation with suicidality.

Results

According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for MDD, 98 patients included and categorized into five clinical subtypes groups: atypical, anxious, melancholic, psychotic, and unspecified depression with percent (11.2%, 31.6%, 19.4%, 15.3%, and 22.4%) respectively. Twenty-four (24.5%) of all patients had suicidal thoughts using Beck Scale for Suicidal Ideation (BSS) with statistically significant increase (P < 0.05*) in suicidality among atypical group. On assessing CRP level, there was highly statistical significant increase (P < 0.001**) among cases with atypical type and also cases with suicidal ideation. Also, logistic regression analysis found that the significant predictors for high CRP among the studied cases were smoking, suicidality, atypical depression, and suicide depression.

Conclusions

Higher level of CRP was found among patients with atypical MDD, and there was significant relationship between CRP and suicidality.

Adjunctive treatment with psychostimulants and stimulant-like drugs for resistant bipolar depression: a systematic review and meta-analysis

BACKGROUND

Depression is considered to be the most difficult to treat phase of bipolar disorder as patients experience residual symptoms causing long-term disability. This work aims to explore the role of add-on stimulant and stimulant-like medication in resistant bipolar depression patients.

METHODS

Systematic review of add-on stimulants and stimulant-like drugs in resistant bipolar depression by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Analysis was performed using the random-effects models. Heterogeneity was evaluated with Cochran's Q and I2 statistics.

RESULTS

Six randomized controlled trials of add-on modafinil, armodafinil, and lisdexamphetamine (LDX) (n = 813) vs placebo (n = 815) in the treatment of resistant bipolar depression were included. These drugs were more likely to induce remission from an episode of resistant bipolar depression (relative risk [RR] = 1.37; 95% confidence interval [CI]: 1.06-1.77; number needed to treat for an additional beneficial outcome = 16). Moreover, they did not induce more dropouts than placebo (RR = 1.04; 95% CI: 0.91-1.18), nor did they increase the risk of adverse effects (53/772 vs 41/771) at the end of treatment (RR = 1.30; 95% CI: 0.81-2.10; number needed to treat for an additional harmful outcome = 62). Suicidality and manic switch were not affected by active treatment. Heterogeneity was low (Cochran's Q: P > .05), but sometimes with a large CI.

CONCLUSIONS

LDX, modafinil, and armodafinil seem to offer a reasonably well-tolerated and safe treatment in resistant bipolar depression. Treatment guidelines should, therefore, be revised to include these medications earlier in the therapeutic algorithm for resistant acute bipolar depression. Further research is, however, necessary for the elucidation of the clinical usefulness of these and other similar compounds.

The Psychopharmacology Algorithm Project at the Harvard South Shore Program: An Update on Unipolar Nonpsychotic Depression

BACKGROUND

The Psychopharmacology Algorithm Project at the Harvard South Shore Program presents evidence-based recommendations considering efficacy, tolerability, safety, and cost. Two previous algorithms for unipolar nonpsychotic depression were published in 1993 and 1998. New studies over the last 20 years suggest that another update is needed.

METHODS

The references reviewed for the previous algorithms were reevaluated, and a new literature search was conducted to identify studies that would either support or alter the previous recommendations. Other guidelines and algorithms were consulted. We considered exceptions to the main algorithm, as for pregnant women and patients with anxious distress, mixed features, or common medical and psychiatric comorbidities.

SUMMARY

For inpatients with severe melancholic depression and acute safety concerns, electroconvulsive therapy (or ketamine if ECT refused or ineffective) may be the first-line treatment. In the absence of an urgent indication, we recommend trialing venlafaxine, mirtazapine, or a tricyclic antidepressant. These may be augmented if necessary with lithium or T3 (triiodothyronine). For inpatients with non-melancholic depression and most depressed outpatients, sertraline, escitalopram, and bupropion are reasonable first choices. If no response, the prescriber (in collaboration with the patient) has many choices for the second trial in this algorithm because there is no clear preference based on evidence, and there are many individual patient considerations to take into account. If no response to the second medication trial, the patient is considered to have a medication treatment-resistant depression. If the patient meets criteria for the atypical features specifier, a monoamine oxidase inhibitor could be considered. If not, reconsider (for the third trial) some of the same options suggested for the second trial. Some other choices can also considered at this stage. If the patient has comorbidities such as chronic pain, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, or posttraumatic stress disorder, the depression could be secondary; evidence-based treatments for those disorders would then be recommended.

Depression in the medically ill

BACKGROUND

Depressive disorders are significantly more common in the medically ill compared to the general population. Depression is associated with worsening of physical symptoms, greater healthcare utilization and poorer treatment adherence. The present paper provides a critical review on the assessment and management of depression in the medically ill.

METHODS

Relevant articles pertaining to depression in the medically ill were identified, reviewed and synthesized qualitatively. A systematic review was not performed due to the large breadth of this topic, making a meaningful summary of all published and unpublished studies not feasible. Notable studies were reviewed and synthesized by a diverse set of experts to provide a balanced summary.

RESULTS

Depression is frequently under-recognized in medical settings. Differential diagnoses include delirium, personality disorders and depressive disorders secondary to substances, medications or another medical condition. Depressive symptoms in the context of an adjustment disorder should be initially managed by supportive psychological approaches. Once a mild to moderate major depressive episode is identified, a stepped care approach should be implemented, starting with general psychoeducation, psychosocial interventions and ongoing monitoring. For moderate to severe symptoms, or mild symptoms that are not responding to low-intensity interventions, the use of antidepressants or higher intensity psychotherapeutic interventions should be considered. Psychotherapeutic interventions have demonstrated benefits with small to moderate effect sizes. Antidepressant medications have also demonstrated benefits with moderate effect sizes; however, special caution is needed in evaluating side effects, drug-drug interactions as well as dose adjustments due to impairment in hepatic metabolism and/or renal clearance. Novel interventions for the treatment of depression and other illness-related psychological symptoms (e.g. death anxiety, loss of dignity) are under investigation.

LIMITATIONS

Non-systematic review of the literature.

CONCLUSION

Replicated evidence has demonstrated a bidirectional interaction between depression and medical illness. Screening and stepped care using pharmacological and non-pharmacological interventions is merited.

Methylphenidate improves executive functions in patients with traumatic brain injuries: a feasibility trial via the idiographic approach

BACKGROUND

Road traffic accidents are known to be the main cause of traumatic brain injury (TBI). TBI is also a leading cause of death and disability. This study, by means of the idiographic approach (single-case experimental designs using multiple-baseline designs), has examined whether methylphenidate (MPH - trade name Ritalin) had a differential effect on cognitive measures among patients with TBI with the sequel of acute and chronic post-concussion syndromes. The effect on gender was also explored.

METHODS

In comparison with healthy controls, patients with TBI (acute and chronic) and accompanying mild cognitive impairment (MCI) were screened for their integrity of executive functioning. Twenty-four patients exhibiting executive dysfunction (ED) were then instituted with the pharmacological intervention methylphenidate (MPH). The methylphenidate was administered using an uncontrolled, open label design.

RESULTS

The administration of methylphenidate impacted ED in the TBI group but had no effect on mood. Attenuation of ED was more apparent in the chronic phases of TBI. The effect on gender was not statistically significant with regard to the observed changes.

CONCLUSIONS

To our knowledge, this is the first feasibility trial from the Arabian Gulf to report the performance of a TBI population with mild cognitive impairment according to the IQCODE Arabic version. This investigation confirms anecdotal observations of methylphenidate having the potential to attenuate cognitive impairment; particularly those functions that are critically involved in the integrity of executive functioning. The present feasibility trial should be followed by nomothetic studies such as those that adhere to the protocol of the randomized controlled trial. This evidence-based research is the foundation for intervention and future resource allocation by policy- or public health decision-makers.

Efficacy and tolerability of adjunctive modafinil/armodafinil in bipolar depression: A meta-analysis of randomized controlled trials

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of the dopaminergic-enhancing agent modafinil/armodafinil (MoArm) as adjunctive treatment for bipolar depression.

METHODS

A comprehensive search of major electronic databases was conducted to identify randomized controlled trials (RCTs) of adjunctive MoArm that included patients with bipolar I (BP-I) or bipolar II (BP-II) depression. Data for response/remission and all-cause discontinuation were analyzed. Effect size was summarized by relative risk (RR) using a random effect model.

RESULTS

Of 58 studies, five RCTs (N = 795 drug, N = 792 placebo) met inclusion criteria. Four armodafinil studies included only BP-I patients and one modafinil study included both bipolar subtypes with limited heterogeneity (I²  = 34%, P = .19; I²  = 18%, P = .30). Compared to placebo, augmentation with MoArm was associated with significantly greater rates of treatment response (RR, 1.18; 95% CI, 1.01-1.37; P = .03) and remission (RR, 1.38; 95% CI, 1.10-1.73; P = .005). All-cause discontinuation was not different than placebo (RR, 1.08; 95% CI, 0.89-1.30; P = .45) with no evidence of increased risk of mood switch or suicide attempts with MoArm (RR, 0.99; 95% CI, 0.39-2.5; P = .98; RR, 1.02; 95% CI, 0.37-2.85; P = .97).

CONCLUSION

This narrower scope meta-analysis of one drug for one disease suggests that adjunctive MoArm may represent a novel therapeutic intervention. Further studies delineating the subtypes of bipolar depression responsive to these novel dopaminergic-enhancing agents are encouraged.

Annual Research Review: Defining and treating pediatric treatment-resistant depression

BACKGROUND

Adolescent major depressive disorder (MDD) is a significant health problem, associated with substantial morbidity, cost, and mortality. Depression is a significant risk factor for suicide, which is now the second leading cause of death in young people. Up to twenty per cent of adolescents will experience MDD before adulthood, and while a substantial proportion will improve with standard-of-care treatments (psychotherapy and medication), roughly one third will not.

METHODS

Here, we have reviewed the literature in order to discuss the concept of treatment-resistant depression (TRD) in adolescence, examine risk factors, diagnostic difficulties, and challenges in evaluating symptom improvement, and providing guidance on how to define adequate medication and psychotherapy treatment trials.

RESULTS

We propose a staging model for adolescent TRD and review the treatment literature. The evidence base for first- and second-line treatments primarily derives from four large pediatric clinical trials (TADS, TORDIA, ADAPT, and IMPACT). After two medications and a trial of evidence-based psychotherapy have failed to alleviate depressive symptoms, the evidence becomes quite thin for subsequent treatments. Here, we review the evidence for the effectiveness of medication switches, medication augmentation, psychotherapy augmentation, and interventional treatments (i.e., transcranial magnetic stimulation, electroconvulsive therapy, and ketamine) for adolescent TRD. Comparisons are drawn to the adult TRD literature, and areas for future pediatric depression research are highlighted.

CONCLUSIONS

As evidence is limited for treatments in this population, a careful consideration of the known risks and side effects of escalated treatments (e.g., mood stabilizers and atypical antipsychotics) is warranted and weighed against potential, but often untested, benefits.

The use of antidepressants in oncology: a review and practical tips for oncologists

Background

The use of psychotropic drugs, namely those with an antidepressant profile (ADs), is a mandatory part of an integrated treatment of psychiatric disorders among cancer patients. We aimed to synthetize the most relevant data emerging from published studies to provide tips about the use of ADs in oncology.

Design

A search was made of the major databases over the last 30 years (Embase/Medline, PsycLIT, PsycINFO, the Cochrane Library), including narrative reviews, systematic reviews and meta-analyses summarizing the results from observational studies and randomized clinical trials assessing effectiveness, safety profile, interactions, contraindications and use of ADs in oncology with regard to both psychiatric (depressive spectrum, stress-related, anxiety disorders) and cancer-related symptoms (e.g. pain, hot flashes and fatigue).

Results

The weight of evidence supports the efficacy of ADs for more severe major depression in individuals with cancer and as an adjuvant treatment in cancer-related symptoms, although the methodological limitations of reported randomized controlled trials do not permit definite conclusions. Data also indicate that there should be caution in the use of ADs in cancer patients in terms of their safety profile and potential clinically significant interactions with other prescribed medications. Practical recommendations that have been made for the use of ADs in cancer patients, in the context of a multimodal approach to depression treatment, have been summarized here.

Conclusions

ADs are a relatively safe and effective treatment for more severe major depression in cancer patients. However, more research is urgently needed regarding the efficacy of ADs in different cancer types and cancer settings, their interactions with anticancer agents and their additive benefit when integrated with psychosocial interventions.

Monoaminergic system and depression

Major depressive disorder is a severe, disabling disorder that affects around 4.7% of the population worldwide. Based on the monoaminergic hypothesis of depression, monoamine reuptake inhibitors have been developed as antidepressants and nowadays, they are used widely in clinical practice. However, these drugs have a limited efficacy and a slow onset of therapeutic action. Several strategies have been implemented to overcome these limitations, including switching to other drugs or introducing combined or augmentation therapies. In clinical practice, the most often used augmenting drugs are lithium, triiodothyronine, atypical antipsychotics, buspirone, and pindolol, although some others are in the pipeline. Moreover, multitarget antidepressants have been developed to improve efficacy. Despite the enormous effort exerted to improve these monoaminergic drugs, they still fail to produce a rapid and sustained antidepressant response in a substantial proportion of depressed patients. Recently, new compounds that target other neurotransmission system, such as the glutamatergic system, have become the focus of research into fast-acting antidepressant agents. These promising alternatives could represent a new pharmacological trend in the management of depression.

A 12-Month Open-Label Extension Study of the Safety and Tolerability of Lisdexamfetamine Dimesylate for Major Depressive Disorder in Adults

PURPOSE/BACKGROUND

Psychostimulant augmentation is considered a potential treatment strategy for individuals with major depressive disorder who do not adequately respond to antidepressant monotherapy. The primary objective of this 12-month open-label extension study was to evaluate the safety and tolerability of lisdexamfetamine dimesylate (LDX) as augmentation therapy to an antidepressant in adults with major depressive disorder.

METHODS/PROCEDURES

Eligible adults who completed 1 of 3 short-term antecedent LDX augmentation of antidepressant monotherapy studies were treated with dose-optimized LDX (20-70 mg) for up to 52 weeks while continuing on the index antidepressant (escitalopram, sertraline, venlafaxine extended-release, or duloxetine) assigned during the antecedent short-term studies. Safety and tolerability assessments included the occurrence of treatment-emergent adverse events and vital sign changes.

FINDINGS/RESULTS

All 3 antecedent studies failed to meet the prespecified primary efficacy endpoint, so this open-label study was terminated early. Headache (15.5% [241/1559]), dry mouth (13.6% [212/1559]), insomnia (13.1% [204/1559]), and decreased appetite (12.1% [189/1559]) were the most frequently reported treatment-emergent adverse events. The greatest mean ± SD increases observed for systolic and diastolic blood pressure and for pulse were 2.6 ± 10.85 and 1.7 ± 7.94 mm Hg and 6.9 ± 10.27 bpm, respectively. Monitoring determined that less than 1% of participants experienced potentially clinically important changes in systolic blood pressure (10 [0.6%]), diastolic blood pressure (8 [0.5%]), or pulse (6 [0.4%]).

IMPLICATIONS/CONCLUSIONS

The overall safety and tolerability of long-term LDX augmentation of antidepressant monotherapy was consistent with the profiles of the short-term antecedent studies, with no evidence of new safety signals.

The pharmacology of amphetamine and methylphenidate: Relevance to the neurobiology of attention-deficit/hyperactivity disorder and other psychiatric comorbidities

Psychostimulants, including amphetamines and methylphenidate, are first-line pharmacotherapies for individuals with attention-deficit/hyperactivity disorder (ADHD). This review aims to educate physicians regarding differences in pharmacology and mechanisms of action between amphetamine and methylphenidate, thus enhancing physician understanding of psychostimulants and their use in managing individuals with ADHD who may have comorbid psychiatric conditions. A systematic literature review of PubMed was conducted in April 2017, focusing on cellular- and brain system-level effects of amphetamine and methylphenidate. The primary pharmacologic effect of both amphetamine and methylphenidate is to increase central dopamine and norepinephrine activity, which impacts executive and attentional function. Amphetamine actions include dopamine and norepinephrine transporter inhibition, vesicular monoamine transporter 2 (VMAT-2) inhibition, and monoamine oxidase activity inhibition. Methylphenidate actions include dopamine and norepinephrine transporter inhibition, agonist activity at the serotonin type 1A receptor, and redistribution of the VMAT-2. There is also evidence for interactions with glutamate and opioid systems. Clinical implications of these actions in individuals with ADHD with comorbid depression, anxiety, substance use disorder, and sleep disturbances are discussed.