Selective serotonin reuptake inhibitors-associated apathy syndrome: A cross sectional study

Effectiveness of Vortioxetine for the Treatment of Emotional Blunting in Patients with Major Depressive Disorder Experiencing Inadequate Response to SSRI/SNRI Monotherapy in Spain: Results from the COMPLETE Study

Background

The multinational, open-label COMPLETE study (NCT03835715) investigated the effectiveness of vortioxetine in alleviating emotional blunting in patients with major depressive disorder (MDD) experiencing inadequate response and emotional blunting while being treated with a selective serotonin reuptake inhibitor (SSRI) or serotonin-noradrenaline reuptake inhibitor (SNRI). This paper presents results for the subgroup of patients enrolled in Spain.

Methods

Patients with MDD (n = 67) experiencing partial response and emotional blunting during monotherapy with an SSRI or SNRI were switched to vortioxetine (10-20 mg/day) for 8 weeks. The primary study outcome was emotional blunting, assessed by the Oxford Depression Questionnaire (ODQ).

Results

After 8 weeks of vortioxetine, the mean (SE) change in ODQ total score from baseline was -26.0 (2.9) (P < 0.001). Respective changes in Montgomery-Åsberg Depression Rating Scale (MADRS), Motivation and Energy Inventory, Digit Symbol Substitution Test, and Sheehan Disability Scale (SDS) total scores were -14.9 (0.8), +34.2 (4.5), +6.3 (1.6), and ‒9.0 (1.3) (all P < 0.001 vs baseline). At week 8, 70.4% of patients no longer reported emotional blunting and 53.7% had achieved remission from their depressive symptoms (defined as a MADRS total score ≤10). Mediation analysis showed 77.1% of the change in SDS total score to be a direct effect of the improvement in ODQ total score after switching to vortioxetine. Adverse events were reported by 35 patients (52.2%), most commonly nausea (14 patients, 20.9%). At week 8, 33/54 patients (61.1%) were receiving vortioxetine 20 mg/day.

Conclusion

In this study investigating the effectiveness of vortioxetine in Spanish patients with MDD who experienced inadequate response and emotional blunting on SSRI/SNRI monotherapy, significant improvements in emotional blunting, core depressive symptoms (including anhedonia), sleep duration, motivation and energy, cognitive performance, and overall patient functioning were observed during the 8 weeks of treatment. Two-thirds of patients no longer reported emotional blunting and over half were in remission from their depressive symptoms at week 8.

Serotonin deficiency from constitutive SKN-1 activation drives pathogen apathy

When an organism encounters a pathogen, the host innate immune system activates to defend against pathogen colonization and toxic xenobiotics produced. C. elegans employ multiple defense systems to ensure survival when exposed to Pseudomonas aeruginosa including activation of the cytoprotective transcription factor SKN-1/NRF2. Although wildtype C. elegans quickly learn to avoid pathogens, here we describe a peculiar apathy-like behavior towards PA14 in animals with constitutive activation of SKN-1, whereby animals choose not to leave and continue to feed on the pathogen even when a non-pathogenic and healthspan-promoting food option is available. Although lacking the urgency to escape the infectious environment, animals with constitutive SKN-1 activity are not oblivious to the presence of the pathogen and display the typical pathogen-induced intestinal distension and eventual demise. SKN-1 activation, specifically in neurons and intestinal tissues, orchestrates a unique transcriptional program which leads to defects in serotonin signaling that is required from both neurons and non-neuronal tissues. Serotonin depletion from SKN-1 activation limits pathogen defense capacity, drives the pathogen-associated apathy behaviors and induces a synthetic sensitivity to selective serotonin reuptake inhibitors. Taken together, our work reveals new insights into how animals perceive environmental pathogens and subsequently alter behavior and cellular programs to promote survival.

KEY POINTS

Identify an apathy-like behavioral response for pathogens resulting from the constitutive activation of the cytoprotective transcription factor SKN-1.Uncover the obligate role for serotonin synthesis in both neuronal and non-neuronal cells for the apathy-like state and ability of serotonin treatment to restore normal behaviors.Characterize the timing and tissue specificity of SKN-1 nuclear localization in neurons and intestinal cells in response to pathogen exposure.Define the unique and context-specific transcriptional signatures of animals with constitutive SKN-1 activation when exposed to pathogenic environments.Reveal necessity for both neuronal and non-neuronal serotonin signaling in host survival from pathogen infection.

Heterogeneity of Response to Methylphenidate in Apathetic Patients in the ADMET 2 Trial

OBJECTIVE

The Apathy in Dementia Methylphenidate Trial 2 (ADMET 2) found that methylphenidate was effective in treating apathy with a small-to-medium effect size but showed heterogeneity in response. We assessed clinical predictors of response to help determine individual likelihood of treatment benefit from methylphenidate.

DESIGN

Univariate and multivariate analyses of 22 clinical predictors of response chosen a priori.

SETTING

Data from the ADMET 2 randomized, placebo controlled multi-center clinical trial.

PARTICIPANTS

Alzheimer's disease patients with clinically significant apathy.

MEASUREMENTS

Apathy assessed with the Neuropsychiatric Inventory apathy domain (NPI-A).

RESULTS

In total, 177 participants (67% male, mean [SD] age 76.4 [7.9], mini-mental state examination 19.3 [4.8]) had 6-months follow up data. Six potential predictors met criteria for inclusion in multivariate modeling. Methylphenidate was more efficacious in participants without NPI anxiety (change in NPI-A -2.21, standard error [SE]:0.60) or agitation (-2.63, SE:0.68), prescribed cholinesterase inhibitors (ChEI) (-2.44, SE:0.62), between 52 and 72 years of age (-2.93, SE:1.05), had 73-80 mm Hg diastolic blood pressure (-2.43, SE: 1.03), and more functional impairment (-2.56, SE:1.16) as measured by the Alzheimer's Disease Cooperative Study Activities of Daily Living scale.

CONCLUSION

Individuals who were not anxious or agitated, younger, prescribed a ChEI, with optimal (73-80 mm Hg) diastolic blood pressure, or having more impaired function were more likely to benefit from methylphenidate compared to placebo. Clinicians may preferentially consider methylphenidate for apathetic AD participants already prescribed a ChEI and without baseline anxiety or agitation.

Understanding neuropsychiatric symptoms in Alzheimer's disease: challenges and advances in diagnosis and treatment

Neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) affect up to 97% of AD patients, with an estimated 80% of current AD patients experiencing these symptoms. Common AD-associated NPS include depression, anxiety, agitation, aggression, and apathy. The severity of NPS in AD is typically linked to the disease's progression and the extent of cognitive decline. Additionally, these symptoms are responsible for a significant increase in morbidity, mortality, caregiver burden, earlier nursing home placement, and greater healthcare expenditure. Despite their high prevalence and significant impact, there is a notable lack of clinical research on NPS in AD. In this article, we explore and analyze the prevalence, symptom manifestations, challenges in diagnosis, and treatment options of NPS associated with AD. Our literature review reveals that distinguishing and accurately diagnosing the NPS associated with AD remains a challenging task in clinical settings. It is often difficult to discern whether NPS are secondary to pathophysiological changes from AD or are comorbid psychiatric conditions. Furthermore, the availability of effective pharmaceutical interventions, as well as non-pharmacotherapies for NPS in AD, remains limited. By highlighting the advance and challenges in diagnosis and treatment of AD-associated NPS, we aspire to offer new insights into the complexity of identifying and treating these symptoms within the context of AD, and contribute to a deeper understanding of the multifaceted nature of NPS in AD.

Apathy associated with antidepressant drugs: a systematic review

OBJECTIVES

Administration of antidepressant drugs - principally selective serotonin reuptake inhibitors (SSRIs) - may induce clinically significant 'apathy' which can affect treatment outcomes adversely. We aimed to review all relevant previous reports.

METHODS

We performed a PUBMED search of English-language studies, combining terms concerning psychopathology (e.g. apathy) and classes of antidepressants (e.g. SSRI).

RESULTS

According to certain inclusion (e.g. use of DSM/ICD diagnostic criteria) and exclusion (e.g. presence of a clinical condition that may induce apathy) criteria, 50 articles were eligible for review. Together, they suggest that administration of antidepressants - usually SSRIs - can induce an apathy syndrome or emotional blunting, i.e. a decrease in emotional responsiveness, to circumstances which would have triggered intense mood reactions prior to pharmacotherapy. The reported prevalence of antidepressant-induced apathy ranges between 5.8 and 50%, and for SSRIs ranges between 20 and 92%. Antidepressant-induced apathy emerges independently of diagnosis, age, and treatment outcome and appears dose-dependent and reversible. The main treatment strategy is dose reduction, though some data suggest the usefulness of treatment with olanzapine, bupropion, agomelatine or amisulpride, or the methylphenidate-modafinil-olanzapine combination.

CONCLUSION

Antidepressant-induced apathy needs careful clinical attention. Further systematic research is needed to investigate the prevalence, course, aetiology, and treatment of this important clinical condition.

Depression in Major Neurodegenerative Diseases and Strokes: A Critical Review of Similarities and Differences among Neurological Disorders

Depression and anxiety are highly prevalent in most neurological disorders and can have a major impact on the patient's disability and quality of life. However, mostly due to the heterogeneity of symptoms and the complexity of the underlying comorbidities, depression can be difficult to diagnose, resulting in limited recognition and in undertreatment. The early detection and treatment of depression simultaneously with the neurological disorder is key to avoiding deterioration and further disability. Although the neurologist should be able to identify and treat depression initially, a neuropsychiatry team should be available for severe cases and those who are unresponsive to treatment. Neurologists should be also aware that in neurodegenerative diseases, such as Alzheimer's or Parkinson's, different depression symptoms could develop at different stages of the disease. The treatment options for depression in neurological diseases include drugs, cognitive-behavioral therapy, and somatic interventions, among others, but often, the evidence-based efficacy is limited and the results are highly variable. Here, we review recent research on the diagnosis and treatment of depression in the context of Alzheimer's disease, Parkinson's disease, and strokes, with the aim of identifying common approaches and solutions for its initial management by the neurologist.

Distinguishing apathy from depression: A review differentiating the behavioral, neuroanatomic, and treatment-related aspects of apathy from depression in neurocognitive disorders

OBJECTIVES

This narrative review describes the clinical features of apathy and depression in individuals with neurocognitive disorders (NCDs), with the goal of differentiating the two syndromes on the basis of clinical presentation, diagnostic criteria, neuropathological features, and contrasting responses to treatments.

METHODS

Literature was identified using PubMed, with search terms to capture medical conditions of interest; additional references were also included based on our collective experience and knowledge of the literature.

RESULTS

Evidence from current literature supports the distinction between the two disorders; apathy and depression occur with varying prevalence in individuals with NCDs, pose different risks of progression to dementia, and have distinct, if overlapping, neurobiological underpinnings. Although apathy is a distinct neuropsychiatric syndrome, distinguishing apathy from depression can be challenging, as both conditions may occur concurrently and share several overlapping features. Apathy is associated with unfavorable outcomes, especially those with neurodegenerative etiologies (e.g., Alzheimer's disease) and is associated with an increased burden for both patients and caregivers. Diagnosing apathy is important not only to serve as the basis for appropriate treatment, but also for the development of novel targeted interventions for this condition. Although there are currently no approved pharmacologic treatments for apathy, the research described in this review supports apathy as a distinct neuropsychiatric condition that warrants specific treatments aimed at alleviating patient disability.

CONCLUSIONS

Despite differences between these disorders, both apathy and depression pose significant challenges to patients, their families, and caregivers; better diagnostics are needed to develop more tailored treatment and support.

Effect of traumatic brain injury on mild behavioral impairment domains prior to all-cause dementia diagnosis and throughout disease progression

Introduction

Traumatic brain injury (TBI) may alter dementia progression, although co-occurring neuropsychiatric symptoms (NPS) have received less attention. Originally designed to evaluate behavioral disruption prior to dementia diagnosis, the mild behavioral impairment (MBI) construct relates NPS to underlying neural circuit disruptions, with probable relevance across the progression of neurodegenerative disease. Therefore, the MBI construct may represent a valuable tool to identify and evaluate related NPS both preceding diagnosis of all-cause dementia throughout the progression of disease, representing an important area of inquiry regarding TBI and dementia. This investigation sought to evaluate the effect of TBI on NPS related by the MBI construct in participants progressing from normal cognitive status to all-cause dementia.

Methods

Using National Alzheimer's Coordinating Center data, individuals progressing from normal cognition to all-cause dementia (clinician diagnosed) over 7.6 ± 3.0 years were studied to estimate prevalence of MBI domains in 124 participants with prior TBI history (57 with loss of consciousness [LOC] <5 minutes, 22 with LOC >5 min, 45 unknown severity) compared to 822 without. MBI domain prevalence was evaluated (1) prior to dementia onset (including only time points preceding time at dementia diagnosis, as per MBI's original definition) and (2) throughout dementia progression (evaluating all available time points, including both before and after dementia diagnosis).

Results

More severe TBI (LOC >5 minutes) was associated with the social inappropriateness MBI domain (adjusted odds ratio = 4.034; P = 0.024) prior to dementia onset, and the abnormal perception/thought content domain looking across dementia progression (adjusted hazard ratio [HRadj] = 3.703; P = 0.005). TBI (all severities) was associated with the decreased motivation domain looking throughout dementia progression (HRadj. = 1.546; P = 0.014).

Discussion

TBI history is associated with particular MBI profiles prior to onset and throughout progression of dementia. Understanding TBI's impact on inter-related NPS may help elucidate underlying neuropathology with implications for surveillance, detection, and treatment of behavioral concerns in aging TBI survivors.

Highlights

The mild behavioral impairment (MBI) construct links related neuropsychiatric symptoms (NPS) by probable underlying neural network dysfunction.Traumatic brain injury (TBI) with loss of consciousness (LOC) > 5 minutes was associated with pre-dementia social inappropriateness.TBI was associated with decreased motivation looking across dementia progression.TBI with LOC > 5 minutes was associated with abnormal perception/thought content.The MBI construct may be useful for examining related NPS across dementia progression.

Apathy, anhedonia and cognitive dysfunction: common symptoms of depression and neurological disorders

Depression is one of the most common mental disorders in neurological practice. Among other symptoms of depression, a symptom complex represented by apathy, anhedonia, and cognitive impairment plays an important role. This review presents the clinical characteristics of the symptoms described above and discusses modern neurochemical and neuroimaging concepts of their pathogenesis. The problem of pathogenetically substantiated therapy of depression with a predominance of apathy, anhedonia and cognitive impairment is discussed. Fundamental and clinical arguments are presented in favor of the high efficacy of vortioxetine in depression with a predominance of apathy, anhedonia, and cognitive impairment. 

Depression: why drugs and electricity are not the answer

The dominant view within mental health services and research suggests that feeling depressed is a kind of medical illness, partially caused by various biological deficits which are somehow corrected by physical interventions. This article critically appraises evidence for the effectiveness and value of antidepressant drugs and electroconvulsive therapy (ECT), the two principle physical treatments recommended for depression. It also describes the negative effects of these interventions and raises concerns about how they impact the brain. We propose an alternative understanding that recognises depression as an emotional and meaningful response to unwanted life events and circumstances. This perspective demands that we address the social conditions that make depression likely and suggests that a combination of politics and common sense needs to guide us in providing help for one another when we are suffering in this way. This alternative view is increasingly endorsed around the world, including by the United Nations, the World Health Organization and service users who have suffered negative consequences of physical treatments that modify brain functions in ways that are not well-understood.

Controversies In The Pharmacotherapy Of Adolescent Depression

BACKGROUND

Although fluoxetine and, in the USA, escitalopram are approved for depression in adolescence, substantial concern surrounds antidepressant use in youth. Major controversies regarding efficacy and safety (increased suicidality).

INTRODUCTION

The cathegory of depression is very broad and overinclusive, in terms of etiology, role of psychosocial adversities severity, episodicity, presentation, relationship with bipolarity. This heterogeneity, not fully controlled considered in Randomized Controlled Trials (RCTs), may account for the disappointing results on both efficacy and safety.

METHOD

Based on the available literature, we will address the following topics: a) controversies regarding the definition of depression as a unique homogeneous condition with a unique type of pharmacological treatment; b) controversies about the interpretation of data from Randomized Controlled Trials (RCTs) on the efficacy of pharmacological treatments in adolescent depression; c) the interpretation of data regarding the safety of antidepressant treatment in adolescent depression, particularly in terms of increased suicidal risk.

RESULTS

According to RCTs, antidepressants are minimally to moderately more effective than placebo, principally based on very high placebo responses, and only fluoxetine showed more evidence of efficacy. These differences in meta-analyses are sometimes statistically, but not clinically significant. Depression is a heterogeneous condition in terms of etiology, role of psychosocial adversities severity, episodicity, presentation, relationship with bipolarity. This heterogeneity may partly explain the low drug-placebo difference and the high placebo response (possibly related to a high level of natural recovery of the adolescent depression). In the National Institute of Mental Health (NIMH)-funded studies, including a lower number of study sites and more reliable enrollment procedures, lower placebo response rates and greater group differences between medication and placebo were found. Robust evidence supports an increased risk of emergent suicidality after starting antidepressants. A clear age effect on suicidal risk after antidepressants is supported by a comprehensive meta-analysis, showing that suicidal risk increased with decreasing age, being markedly greater in subjects aged between 18 and 25 years. However, the term suicidality is too broad, as it includes suicidal ideation, suicidal attempts, and completed suicide, with a hugely wide range of severity and pervasiveness. If emergent suicidality should be actively and carefully explored, empirical evidence, albeit weak, suggests that combined pharmacotherapy (antidepressant and/or lithium) associated with psychotherapy may be helpful in reducing pretreatment suicidal ideation and suicidal risk.

DISCUSSION

Moderate to severe depression should be treated with psychotherapy and/or fluoxetine, the best-supported medication, and treatment-resistant adolescents should always receive combined treatment with psychotherapy. Suicidal ideation, particularly with a plan, should be actively explored before starting an antidepressant, as a reason for the closest monitoring. Emergent suicidality after starting antidepressants, as well as antidepressant-related activation, should also be closely monitored and may lead to antidepressant discontinuation. Although no response to pharmacotherapy and psychotherapy may occur in up to 40% of depressed adolescents, possible predictors or mediators of poorer response in adolescents are uncertain, and only a few studies support possible treatment strategies. Finally, studies exploring the efficacy of antidepressants in specific depression subtypes, i.e., based on prevalent psychopathological dimensions (apathy, withdrawal, impulsivity), are warranted.

Frequently reported adverse events of rebamipide compared to other drugs for peptic ulcer and gastroesophageal reflux disease

This study aimed to detect safety signals of rebamipide and search for adverse events (AEs) of rebamipide that are more common than those of other drugs for peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD) in the elderly population. A total of 101,735 AE reports for drugs used to treat PUD and GERD between 2009 and 2018 from the KIDS-KAERS database (KIDS-KD) were used. Disproportionality analysis was performed to calculate the proportional reporting ratio (PRR), reporting odds ratio (ROR), and information component (IC). Drug labels in Korea, Japan, and China were reviewed to identify signals that have been listed. AEs frequently reported in the elderly population were also analyzed. Seriousness and median time to AEs were evaluated for statistically significant AEs. A total of 14 signals were detected, and 4 signals (dry mouth, dermatitis, purpura/petechia, and fluid overload) were not listed on drug labels; however, they may be included as part of other listed AEs. In the elderly population, 11 AEs such as dyspepsia/indigestion/gastrointestinal distress, somnolence, dry mouth, and edema were common. These AEs were not serious and occurred within 2–9 days. This study identified possible AEs of rebamipide, a relatively safe drug.

Depression and Dementia in Older Adults: A Neuropsychological Review

Depression and dementia are the most common neuropsychiatric disorders in the older adult population. There are a certain number of depressed patients who visit outpatient clinics because they suspect dementia due to similarities in the clinical symptoms in both disorders. Depressive symptoms associated with dementia may be diagnosed with depression, and treatment with antidepressants is continued for a long time. Depression and dementia differ in their treatment approaches and subsequent courses, and it is necessary to carefully differentiate between the two in the clinical practice of dementia treatment. In this review, I describe the similarities between depression and dementia and how to differentiate depression in dementia treatment based on the differences and emphasize that there is a significant potential to cure depression, in contrast to dementia, for which there is currently no fundamental therapy. Therefore, it is important to recognize that depression and dementia may present with common symptoms and to appropriately differentiate depressed patients who are suspected of having dementia. Dementia is a disorder in which cognitive dysfunction is caused by a variety of causative diseases and conditions, resulting in impairment of activities of daily living. However, current medical science has had difficulty finding a cure for the causative disease. Based on clinical findings, it has also been shown that the degree of symptoms for preexisting psychiatric disorders is alleviated as the brain ages. In the presence of dementia, the speed of the alleviation will increase. The importance of focusing on the positive aspects of aging is also discussed.

Effect of Methylphenidate on Apathy in Patients With Alzheimer Disease: The ADMET 2 Randomized Clinical Trial

Importance

Apathy, characterized by diminished will or initiative and one of the most prevalent neuropsychiatric symptoms in individuals with Alzheimer disease, is associated with significant caregiver burden, excess disability, increased medical costs, and mortality.

Objective

To measure whether methylphenidate compared with placebo decreases the severity of apathy in individuals with Alzheimer disease.

Design, Setting, and participants

This multicenter randomized placebo-controlled clinical trial was conducted from August 2016 to July 2020 in 9 US clinics and 1 Canadian clinic specializing in dementia care. A total of 307 potential participants were screened. Of those, 52 did not pass screening and 55 were not eligible. Participants with Alzheimer disease, mild to moderate cognitive impairment, and frequent and/or severe apathy as measured by the Neuropsychiatric Inventory (NPI) were included.

Interventions

Ten milligrams of methylphenidate, twice daily, vs matching placebo.

Main Outcomes and Measures

The coprimary outcomes included (1) change from baseline to 6 months in the NPI apathy subscale or (2) improved rating on the Alzheimer's Disease Cooperative Study Clinical Global Impression of Change. Other outcomes include safety, change in cognition, and quality of life.

Results

Of 200 participants, 99 were assigned to methylphenidate and 101 to placebo. The median (interquartile range) age of study participants was 76 (71-81) years; 68 (34%) were female and 131 (66%) were male. A larger decrease was found from baseline to 6 months in the NPI apathy score in those receiving methylphenidate compared with placebo (mean difference, -1.25; 95% CI, -2.03 to -0.47; P = .002). The largest decrease in the NPI apathy score was observed in the first 100 days, with a significant hazard ratio for the proportion of participants with no apathy symptoms receiving methylphenidate compared with placebo (hazard ratio, 2.16; 95% CI, 1.19-3.91; P = .01). At 6 months, the odds ratio of having an improved rating on the Alzheimer's Disease Cooperative Study Clinical Global Impression of Change for methylphenidate compared with placebo was 1.90 (95% CI, 0.95-3.84; P = .07). The difference in mean change from baseline to 6 months estimated using a longitudinal model was 1.43 (95% CI, 1.00-2.04; P = .048). Cognitive measures and quality of life were not significantly different between groups. Of the 17 serious adverse events that occurred during the study, none were related to the study drug. No significant differences in the safety profile were noted between treatment groups.

Conclusions and Relevance

This study found methylphenidate to be a safe and efficacious medication to use in the treatment of apathy in Alzheimer disease.

Trial Registration

ClinicalTrials.gov Identifier: NCT02346201.

The use of the French Dimensional Apathy Scale (f-DAS) to assess apathy in schizophrenia: Properties and profiles

BACKGROUND

Apathy can be defined as a quantitative reduction of self-generated voluntary and purposeful (or goal-directed) behaviour. The literature underlines the triadic dimensional nature of apathy, but in schizophrenia there are inconsistencies due to difficulty in assessment. The Dimensional Apathy Scale (DAS) and its validation into French (f-DAS) provide measurement of three neurobehavioral apathy subtypes: Executive, Emotional and Initiation, but these subtypes have never been explored in schizophrenia.

OBJECTIVE

The aims of this study are to assess apathy in schizophrenia with a tri-dimensional tool (the f-DAS), to examine its psychometric properties in schizophrenia and the apathetic profiles of patients with schizophrenia.

METHODS

One hundred and ten subjects were recruited. Forty-five belonged to the patients' group and fifty-five to the control group. They all completed the Mini-International Neuropsychiatric Interview (M.I.N.I), the French National Reading Test (f-NART), the French Dimensional Apathy Scale (f-DAS), the Lille Apathy Rating Scale (LARS) and the Beck Depression Inventory (BDI II).

RESULTS

Regarding the total score of the f-DAS and the subscores for each dimension, patients appeared significantly more apathetic than healthy controls. Consistency, validity, concurrent and divergent validity were good. In the patient group, several profiles of apathy were identified.

CONCLUSIONS

The f-DAS has good psychometric properties and provides reliable and valid dimensional assessment of apathy in schizophrenia. From a dimensional point of view, using the f-DAS we demonstrated that prevalence of apathy could be underestimated in schizophrenia. Patients with schizophrenia are more impaired on the Executive and Initiative dimensions of apathy.