Clinical correlates of anhedonia in patients with Parkinson's disease

Association between overt aggression and anhedonia in patients with major depressive disorder during the acute phase

OBJECTIVE

To explore the factors influencing anhedonia at baseline and use them as confounding factors. To further investigate the correlation between overt aggression and anhedonia during the acute phase of major depressive disorder.

METHODS

In this eight-week prospective study, 384 major depressive disorder patients were recruited from the outpatient section of Shanghai Mental Health Center from May 1, 2017, to October 30, 2018. Standard treatments were performed with escitalopram or venlafaxine for participants. Depressive symptoms, overt aggression, and anhedonia were assessed using the 17-item Hamilton Rating Scale for Depression, Modified Overt Aggression Scale, and Snaith-Hamilton Pleasure Scale at baseline, and in the 4th and 8th weeks.

RESULTS

Obsessive-compulsive symptoms and the duration of untreated psychosis were positively associated with aggression (P < 0.05). Patients with aggressive behaviour had worse cognitive impairment and severe anhedonia of pleasurable sensory experiences (P < 0.05). For anhedonia, being female (tau_b = -0.23, P = 0.012) was a protective factor, while number of recurrent, melancholic features, current obsessions, previous combination drug therapies, depressive symptoms, and aggressive behaviour were risk factors (P < 0.05). Social anhedonia related to interests/pastimes, and pleasurable sensory experiences were more severe in major depressive disorder patients with aggressive behaviour in the acute phase (P < 0.05).

CONCLUSIONS

Anhedonia persisted in major depressive disorder patients with aggressive behaviour after standardized treatment during the acute phase. Being female protected the pleasures from social interaction and sensory experience. However, the number of depressive episodes, melancholic features, current obsessive symptoms, previous combination drug therapies, depressive symptoms, and aggressive behaviour was positively associated with anhedonia.

Anhedonia in epilepsy

BACKGROUND

Anhedonia, the impaired ability to experience pleasure, is a core feature of major depressive disorder, one of the most common comorbidities in epilepsy. It is also reported as a clinical feature independent of depression in a number of other neurological conditions. This study aimed to establish the prevalence of anhedonia in a sample of people with epilepsy, with and without a diagnosis of depression, and to examine the clinical and demographic characteristics of those who present with this symptom.

METHODS

A consecutive sample of 211 people (118 female, 93 male, mean age 38.09 years) completed the Snaith-Hamilton Pleasure Scale (SHAPS) to determine the presence of anhedonia and the Hospital Anxiety and Depression Scale to determine levels of anxiety and depression. The majority of patients had focal epilepsy (n = 165), and the remaining patients had generalized epilepsy (n = 22), or unclassified epilepsy (n = 24). Sixteen percent of the sample had a clinical diagnosis of depression at the time of the study.

RESULTS

Over one in three of the sample (35%) reported significant anhedonia on the SHAPS. While these patients were more likely to have a diagnosis of depression (p < 0.01), 30% of people without a diagnosis of depression also reported significant anhedonia. Difficulties gaining pleasure on 12 of the 14 items on the SHAPS were associated with cognitive difficulties, with those reporting an inability to feel pleasure on the item scoring significantly lower on tests of cognitive function than those who were able to gain pleasure. Of the three cognitive domains examined (overall intellectual ability, verbal memory, and processing speed), a poor memory had the strongest relationship; with lower memory function associated with an impaired ability to experience pleasure on 9 of the 14 items.

CONCLUSION

While anhedonia is well recognized as a feature of depression, our data suggests that it can be present in up to a third of people with epilepsy who do not have a diagnosis of depression. Cognitive difficulties, particularly impaired memory function may mediate some features of anhedonia. The implications of these findings for the clinical management of anhedonia in people with epilepsy are discussed.

Anhedonia in Neurodegenerative Diseases

Neurodegenerative diseases are increasingly recognised to be an important cause of brain disorders, particularly in late age. Associated with a wide range of pathologies, they lead to progressive loss of neurons in different regions of the nervous system. Although anhedonia is common in a variety of neurodegenerative diseases, to date it has not been extensively studied in most of these conditions. Here we review the current literature on studies assessing the association between anhedonia and neurodegenerative diseases including Parkinson's Disease, Dementia with Lewy Bodies, Parkinson's Plus Syndromes, Alzheimer's Disease, Vascular Dementia, Frontotemporal Dementia, Amyotrophic Lateral Sclerosis and Huntington's Disease. Much of the research has been conducted in Parkinson's disease where it is evident that there are strong links between apathy (loss of motivation) and anhedonia, although the two syndromes can be dissociated. Intriguingly, drugs that improve apathy can also lead to amelioration of anhedonia in some cases. Overlaps between the two syndromes may also exist across other neurodegenerative conditions, including Frontotemporal Dementia in which imaging has revealed atrophy of both common brain regions associated with anhedonia and apathy, as well as a set of unique brain regions associated with anhedonia. A transdiagnostic perspective might be helpful to investigate whether a common network of brain regions is dysfunctional with anhedonia across neurodegenerative conditions.

Fatigue in de novo Parkinson's Disease: Expanding the Neuropsychiatric Triad?

BACKGROUND

Fatigue is a frequent and troublesome symptom present from the early stages of Parkinson's disease (PD).

OBJECTIVE

To examine the relationship between fatigue and the neuropsychiatric triad, which includes apathy, depression, and anxiety, in de novo PD.

METHODS

We performed a cross-sectional study including 197 patients with de novo PD and assessed fatigue using the Parkinson's Disease Fatigue Scale (PDFS-16). We evaluated motor status using the Unified Parkinson's Disease Rating Scale (UPDRS) part III score and evaluated neuropsychiatric status using the Ardouin Scale of Behavior in Parkinson's Disease (ASBPD). We carried out univariate and multivariate analyses to model association between motor signs, non-motor signs, and fatigue risk.

RESULTS

Frequency of fatigue (28.9%) was of the same order of magnitude as that of apathy. PD patients with fatigue reported a lower quality of life than patients without fatigue (p < 0.0001). The ASBPD showed that patients with fatigue had higher scores for depressed mood (p < 0.0001), anxiety (p < 0.0001), and apathy (p < 0.0001). In the univariate analysis, fatigue score was positively correlated with apathy, depression, anxiety, and the neuropsychiatric triad as a whole, and to a lesser extent with female sex, hyperemotivity, and the UPDRS part III score. In the multivariate analysis, after adjusting for sex and motor status, the fatigue score remained significantly correlated with apathy (OR = 11.17 [4.33-28.78], p < 0.0001) and depression (OR = 4.28 [1.39-13.12], p = 0.01), but not with anxiety (OR = 0.94 [0.34-2.58], p = 0.9).

CONCLUSION

We propose that the neuropsychiatric triad could be expanded to include fatigue.

Apathy and Anhedonia: Clinical and Neurophysiological Assessment of a Romanian Cohort

Background: Patients with Parkinson’s disease (PD) often have, besides the characteristic motor manifestations, a wide variety of non-motor symptoms. These include apathy and anhedonia, common issues in PD, which can be quantified with the help of evaluation scales recommended by the literature. There are sensory non-motor manifestations of PD, some of which are easy to detect through electrophysiological studies. Our aim was to investigate the possible association of apathy and anhedonia with the severity of the motor status in a sample of PD patients in Romania. We also examined the prevalence of latency changes in the P100 wave of visual evoked potentials (VEPs) and how they correlated with motor status, apathy, and anhedonia in PD patients. Methods: Thirty-four patients with PD participated in this study. All were assessed for motor status using the Unified Parkinson’s Disease Rating Scale (UPDRS) and were rated on the Hoehn and Yahr scales. The presence and severity of apathy and anhedonia were assessed using the Apathy Evaluation Scale (AES), the Dimensional Apathy Scale (DAS), the Lille Apathy Rating Scale (LARS), and the Snaith–Hamilton Pleasure Scale (SHAPS). The latency of the P100 wave of the VEP was measured in all the patients. Results: Apathy and anhedonia were common among the patients with PD (35% and 58.8%, respectively). The presence of apathy/anhedonia was correlated with the severity of motor symptoms, as assessed using the UPDRS scale (p < 0.001), and with the stage of the disease according to the Hoehn and Yahr scale (p < 0.001). A prolonged latency of the P100 wave of the VEP was observed among apathetic (p < 0.001)/anhedonic (p < 0.01) patients and those with increased disease severity (p < 0.001). Conclusion: Apathy and anhedonia are common in PD and may correlate with the severity of motor symptoms. There may be visual impairment in these patients, evidenced by a prolonged P100 latency, which correlates with the severity of disease. Significance: Scales for assessing apathy and anhedonia, as well as measuring VEP latency, could be useful in assessing the severity of disease.

Decreased emotional creativity and its relationship with cognitive functions in Parkinson's disease: A preliminary study

Patients with Parkinson's disease (PD) suffer from a wide range of non-motor symptoms, including cognitive deficits and impairment of emotional processing. The present study aimed to explore in PD patients compared to healthy adults the relationship between cognitive performance and emotional creativity (EC), defined as a set of cognitive abilities and personality traits related to originality and appropriateness of emotional experience. PD patients (n = 22) and healthy controls (n = 40) underwent a complex neuropsychological assessment and were administrated with the self-reported Emotional Creativity Inventory (ECI) questionnaire. To explore the relationship between cognitive tests and the ECI, a regression analysis was conducted. PD patients and healthy controls differed significantly in the EC component Preparedness as well as in the neuropsychological test battery scores. PD patients showed lower scores in cognitive tests and a lower score in Preparedness compared to healthy adults. The output of the regression analysis showed that the extent to which the neuropsychological tests relate to the ECI components is low.

Differences in correlations of depression and anhedonia with cardiovascular sympathetic functions during a head-up tilt test in drug-naïve Parkinson's disease patients

BACKGROUND

Depression is a symptom of Parkinson's disease (PD) and may be correlated with cardiovascular sympathetic function. Anhedonia is an element of depression, but these symptoms can emerge independently in PD. A correlation of anhedonia with cardiovascular sympathetic function has rarely been examined.

OBJECTIVE

To compare correlations of depression and anhedonia with cardiovascular sympathetic function in drug-naive PD patients.

METHODS

Assessments of depression (Self-rating Depression Scale; SDS), anhedonia (Snaith-Hamilton Pleasure Scale; SHAPS), myocardial ¹²³I-MIBG (¹²³I-meta-iodobenzylguanidine) scintigraphy (heart to mediastinum (H/M) ratios in early and delayed images), and head-up tilt test (HUT) up to 60° for 10 min were performed in 45 drug-naïve PD patients. During the HUT, blood pressure was measured every minute and the maximum decrease in systolic blood pressure (SBP) was determined. Plasma noradrenaline (NA) and arginine vasopressin (AVP) levels were examined at baseline and 10 min after tilt, with subsequent calculation of increases in plasma NA and AVP levels in this 10 min. Correlation coefficients were calculated among these assessment parameters.

RESULTS

SDS significantly correlated with % maximum decrease in SBP (r = 0.344, p = 0.02), but not with H/M ratios in both images and increases in plasma NA and AVP levels. SHAPS did not correlate with the change in SBP, H/M ratios in both images, or plasma NA and AVP levels.

CONCLUSION

Depression was correlated with the % maximum decrease in SBP during a 10-min HUT, but anhedonia did not show this relationship. This suggests that depression and anhedonia may have different pathophysiological backgrounds in drug-naïve PD patients.

Anti-cytokine agents for anhedonia: targeting inflammation and the immune system to treat dimensional disturbances in depression

The etiology of mood disorders is mechanistically heterogeneous, underscoring the need for a dimensional approach to identify and develop targeted treatments in psychiatry. Accumulating evidence implicates inflammation as an important contributor to the pathophysiology of depression and presents the immune system as a viable therapeutic target that may be more proximate to the pathogenic nexus of brain-based disorders in specific subpopulations. Anhedonia is a transdiagnostic (e.g. Parkinson's disease, diabetes mellitus, rheumatic diseases), yet specific, and clinically relevant symptom dimension subserved by well-characterized neurobiological and neurophysiological substrates of the positive valence systems (PVS). Brain circuits, nodes, and networks, as well as cellular and molecular pathways (e.g. dopaminergic transmission; excitotoxicity; synaptic plasticity), subserving anhedonia are preferentially affected by inflammatory processes. To our knowledge, no published randomized, controlled clinical trial in populations with mood disorders has, to date, primarily sought to determine the effects of an anti-inflammatory agent on PVS functions or pathophysiology. Three ongoing clinical trials aim to investigate the effects of anti-TNF-alpha biologic infliximab on measures of anhedonia [ClinicalTrials.gov identifier: NCT02363738], motivational behavior and circuitry [ClinicalTrials.gov identifier: NCT03006393], and glutamatergic changes in the basal ganglia [ClinicalTrials.gov identifier: NCT03004443] in clinical populations with unipolar or bipolar depression. Positive results would further instantiate the relevance of inflammatory processes and the immune system in the pathophysiology of mood disorders and provide the impetus to develop scalable treatments targeting inflammation and the immune system to mitigate transdiagnostic, dimensional disturbances in brain-based disorders.

The pathophysiological mechanisms of motivational deficits in Parkinson's disease

Parkinson's disease (PD) is a progressive degenerative disorder that leads to disabling motor symptoms and a wide variety of neuropsychiatric symptoms. Apathy is the most common psychiatric disorder in the early stages of untreated PD and can be defined as a hypodopaminergic syndrome, which also includes anxiety and depression. Apathy is also considered the core feature of the parkinsonian triad (apathy, anxiety and depression) of behavioural non-motor signs, including a motivational deficit. Moreover, apathy is recognised as a distinct chronic neuropsychiatric behavioural disorder based on specific diagnostic criteria. Given the prevalence of apathy in approximately 40% of the general Parkinson's disease population, this appears to be a contributing factor to dementia in PD; also, apathy symptoms are factors that potentially contribute to morbidity, leading to a major impairment of health-related quality of life, thus stressing the importance of understanding the pathophysiology of this disease. Several studies have clearly established a prominent role for DA-mediated signals in PD apathy. However, synergistic interaction between dopaminergic impairment resulting from the neurodegenerative process and deep brain stimulation of the subthalamic nucleus may cause or exacerbate apathy. Furthermore, serotoninergic mechanism signalling is also likely to be of importance in this pathophysiology.

Assessment of Snaith-Hamilton Pleasure Scale (SHAPS): the dimension of anhedonia in Italian healthy sample

The Snaith-Hamilton Pleasure Scale (SHAPS) is a rapid screening battery created for assessing the presence of anhedonia, namely the inability to experience pleasure. Although, this symptom has widely been investigated in clinical settings, individual differences in anhedonia are also present in healthy population. The aim of present study was to validate the translated Italian version of this test. One thousand six hundred ninety-seven consecutive healthy subjects (55% female) of different ages (age 18-82 years) underwent SHAPS. Participants who showed mild level of anhedonia also completed the Apathy Evaluation Scale (AES), Beck Depression Inventory (BDI), Toronto Alexithymia Scale-20 (TAS), Mood Disorders Insight Scale (MDIS), and Beck Hopelessness Scale (BHS). The SHAPS showed good internal consistency and discriminant validity; moreover, the factorial analysis highlighted that SHAPS had a three-factor structure for explaining the anhedonic construct. 14.9% showed a significant reduction of hedonic tone (SHAPS ≥ 3). Finally, the degree of anhedonia was significantly correlated with BDI and BHS scores, but not with age or gender. Although anhedonia is a prominent feature of many psychiatric and neurological disorders, the presence of this symptom in the healthy population highlighted the importance to develop reliable tool. SHAPS shows good psychometric properties to assess multidimensional anhedonia symptoms also in Italian healthy population.

Clinical Presentation of Anxiety in Parkinson's Disease: A Scoping Review

Up to 40% of all individuals with Parkinson's disease (PD) are estimated to experience anxiety that interferes with daily functioning. This article describes research regarding the presentation of anxiety in PD and the influence anxiety has on participation in this population. A scoping review identified 1,635 articles, of which 49 met the inclusion criteria. This review identified that anxiety in PD is often associated with a range of clinical correlates related to demographic and clinical characteristics (age, gender, disease stage, duration, progression), motor symptoms (tremor, bradykinesia, dystonia, freezing of gait, symptom severity), treatment-related complications (on/off fluctuations, on with dyskinesia, unpredictable off), and non-motor symptoms (sleep abnormalities, fatigue, cognitive impairment, depression). These findings can be used to increase clinicians' awareness toward the specific clinical correlates linked to anxiety in PD so that mental health concerns can be detected and addressed more readily in practice.

Psychiatric Conditions in Parkinson Disease: A Comparison With Classical Psychiatric Disorders

Psychiatric conditions often complicate the outcome of patients affected by Parkinson disease (PD), but they differ from classical psychiatric disorders in terms of underlying biological mechanisms, clinical presentation, and treatment response. The purpose of the present review is to illustrate the biological and clinical aspects of psychiatric conditions associated with PD, with particular reference to the differences with respect to classical psychiatric disorders. A careful search of articles on main databases was performed in order to obtain a comprehensive review about the main psychiatric conditions associated with PD. A manual selection of the articles was then performed in order to consider only those articles that concerned with the topic of the review. Psychiatric conditions in patients with PD present substantial differences with respect to classical psychiatric disorders. Their clinical presentation does not align with the symptom profiles represented by Diagnostic and Statistical Manual for Mental Disorders and International Classification of Diseases. Furthermore, psychiatry treatment guidelines are of poor help in managing psychiatric symptoms of patients with PD. Specific diagnostic tools and treatment guidelines are needed to allow early diagnosis and adequate treatment of psychiatric conditions in comorbidity with PD.

Trait Impulsivity and Anhedonia: Two Gateways for the Development of Impulse Control Disorders in Parkinson's Disease?

Apathy and impulsivity are two major comorbid syndromes of Parkinson's disease (PD) that may represent two extremes of a behavioral spectrum modulated by dopamine-dependent processes. PD is characterized by a progressive loss of dopaminergic neurons in the substantia nigra pars compacta to which are attributed the cardinal motor symptoms of the disorder. Dopamine replacement therapy (DRT), used widely to treat these motor symptoms, is often associated with deficits in hedonic processing and motivation, including apathy and depression, as well as impulse control disorders (ICDs). ICDs comprise pathological gambling, hypersexuality, compulsive shopping, binge eating, compulsive overuse of dopaminergic medication, and punding. More frequently observed in males with early onset PD, ICDs are associated not only with comorbid affective symptoms, such as depression and anxiety, but also with behavioral traits, such as novelty seeking and impulsivity, as well as with personal or familial history of alcohol use. This constellation of associated risk factors highlights the importance of inter-individual differences in the vulnerability to develop comorbid psychiatric disorders in PD patients. Additionally, withdrawal from DRT in patients with ICDs frequently unmasks a severe apathetic state, suggesting that apathy and ICDs may be caused by overlapping neurobiological mechanisms within the cortico-striato-thalamo-cortical networks. We suggest that altered hedonic and impulse control processes represent distinct prodromal substrates for the development of these psychiatric symptoms, the etiopathogenic mechanisms of which remain unknown. Specifically, we argue that deficits in hedonic and motivational states and impulse control are mediated by overlapping, yet dissociable, neural mechanisms that differentially interact with DRT to promote the emergence of ICDs in vulnerable individuals. Thus, we provide a novel heuristic framework for basic and clinical research to better define and treat comorbid ICDs in PD.

From sweet to sweat: Hedonic olfactory range is impaired in Parkinson's disease

INTRODUCTION

Olfactory dysfunction and neuropsychological symptoms like depression and anhedonia are common non-motor symptoms in Parkinson's disease (PD). The assessment of both functional domains includes clinical examination, olfactory testing, and standardized questionnaires. While olfaction is readily assessed by functional tests, the distinction of anhedonia as a separate symptom from other depressive symptoms is challenging. Thus, a test focusing on the assessment of hedonic olfaction may be helpful in the assessment of neuropsychological symptoms in PD.

METHODS

We examined anhedonia by evaluating the perception of pleasantness of odors in PD patients (n = 57) and healthy controls (n = 46). Pleasantness of odors was registered on a visual 9-point scale. For the assessment of anhedonia we used the Snaith-Hamilton-Pleasure-Scale (SHAPS). Depression was evaluated with the Zung Self-Rating Depression Scale and the Beck Depression Inventory II.

RESULTS

PD patients showed a substantial reduction in hedonic olfaction compared to controls (hedonic score: 1.5 vs. 2.2). Hyposmia, one of the most prevalent non-motor symptoms in PD, was a confounding factor. However, even normosmic PD patients showed a reduced hedonic olfaction compared to controls (hedonic score: 1.6 vs. 2.2). Furthermore, we observed a correlation between hedonic olfaction and the SHAPS-score for PD patients even though positive SHAPS-rating was observed in 9% of PD patients only, while no correlation to depression was present.

CONCLUSION

These findings suggest that reduced hedonic olfaction might be an additional neuropsychological feature, probably giving insights into changes in hedonic tone complementary to hyposmia and depression in PD.