Prevalence, clinical manifestations, etiology, and treatment of depression in Parkinson's disease

Neural stem cells in Parkinson's disease: a role for neurogenesis defects in onset and progression

Parkinson's disease (PD) is the second most common neurodegenerative disorder, leading to a variety of motor and non-motor symptoms. Interestingly, non-motor symptoms often appear a decade or more before the first signs of motor symptoms. Some of these non-motor symptoms are remarkably similar to those observed in cases of impaired neurogenesis and several PD-related genes have been shown to play a role in embryonic or adult neurogenesis. Indeed, animal models deficient in Nurr1, Pitx3, SNCA and PINK1 display deregulated embryonic neurogenesis and LRRK2 and VPS35 have been implicated in neuronal development-related processes such as Wnt/β-catenin signaling and neurite outgrowth. Moreover, adult neurogenesis is affected in both PD patients and PD animal models and is regulated by dopamine and dopaminergic (DA) receptors, by chronic neuroinflammation, such as that observed in PD, and by differential expression of wild-type or mutant forms of PD-related genes. Indeed, an increasing number of in vivo studies demonstrate a role for SNCA and LRRK2 in adult neurogenesis and in the generation and maintenance of DA neurons. Finally, the roles of PD-related genes, SNCA, LRRK2, VPS35, Parkin, PINK1 and DJ-1 have been studied in NSCs, progenitor cells and induced pluripotent stem cells, demonstrating a role for some of these genes in stem/progenitor cell proliferation and maintenance. Together, these studies strongly suggest a link between deregulated neurogenesis and the onset and progression of PD and present strong evidence that, in addition to a neurodegenerative disorder, PD can also be regarded as a developmental disorder.

Influence of depressive symptoms on dopaminergic treatment of Parkinson's disease

Introduction: Depressive symptoms are very common in patients with Parkinson’s disease (PD) and have a significant impact on the quality of life. Dopaminergic medication has been shown to have an influence on the development of depressive symptoms.

Materials and methods: The present study analyzed two groups of non-demented patients with PD, with and without depressive symptoms, and reported the correlations between antiparkinsonian medication [specifically levodopa (l-DOPA) and dopaminergic agonists] with depressive symptoms.

Results: A strong statistically significant positive correlation between l-DOPA dosages and the level of depressive symptoms has been revealed, suggesting that higher l-DOPA dosages correlate with a worsening of depressive status. No significant correlation was found with dopamine agonists.

Discussion: The results of this study show that in patients with PD, higher l-DOPA dosages correlate with worse depressive symptoms. From this point of view, PD patients need to be better diagnosed with respect to depressive symptoms and need additional treatment adjustment when clinical manifestations of depression are present. Clinicians must be aware that dopaminergic drugs are not sufficient to alleviate depressive symptoms.

Mixed effects of deep brain stimulation on depressive symptomatology in Parkinson's disease: a review of randomized clinical trials

Although ~50% of patients with Parkinson’s disease (PD) experience depression, treatment for this important and debilitating comorbidity is relatively understudied. Deep brain stimulation (DBS) has been increasingly utilized for the management of tremors in progressive PD. Several preliminary studies have shown the potential benefit of DBS for non-motor PD symptoms such as depression. Here, we critically evaluate seven recent randomized clinical trials of the effectiveness of DBS in reducing depressive symptomatology among individuals with PD. Findings are mixed for the effectiveness of DBS as a treatment for depression in PD. Our review suggests that this is due, in large part, to the anatomical and methodological variation across the DBS studies. We provide a comprehensive discussion of these variations and highlight the need to conduct larger, more controlled studies aimed specifically at evaluating the treatment of depression in PD patients.

Depression and Parkinson's disease: current knowledge

Depressive disturbances are common in patients with Parkinson's disease (PD) and influence many other clinical aspects of the disease. In addition to causing inherent emotional distress, depressive disorders negatively impact quality of life, motor and cognitive deficits, functional disability, and other psychiatric comorbidities in patients with PD. Knowledge of the pathophysiology of PD depression remains limited. However, clinical studies demonstrate the efficacy of medications and psychotherapies for PD depression, underscoring the importance of their timely detection and concerted management.

Preconditioning as a potential strategy for the prevention of Parkinson's disease

Parkinson's disease (PD) is a chronic neurodegenerative movement disorder characterized by the progressive and massive loss of dopaminergic neurons by neuronal apoptosis in the substantia nigra pars compacta and depletion of dopamine in the striatum, which lead to pathological and clinical abnormalities. A numerous of cellular processes including oxidative stress, mitochondrial dysfunction, and accumulation of α-synuclein aggregates are considered to contribute to the pathogenesis of Parkinson's disease. A further understanding of the cellular and molecular mechanisms involved in the pathophysiology of PD is crucial for developing effective diagnostic, preventative, and therapeutic strategies to cure this devastating disorder. Preconditioning (PC) is assumed as a natural adaptive process whereby a subthreshold stimulus can promote protection against a subsequent lethal stimulus in the brain as well as in other tissues that affords robust brain tolerance facing neurodegenerative insults. Multiple lines of evidence have demonstrated that preconditioning as a possible neuroprotective technique may reduce the neural deficits associated with neurodegenerative diseases such as PD. Throughout the last few decades, a lot of efforts have been made to discover the molecular determinants involved in preconditioning-induced protective responses; although, the accurate mechanisms underlying this "tolerance" phenomenon are not fully understood in PD. In this review, we will summarize pathophysiology and current therapeutic approaches in PD and discuss about preconditioning in PD as a potential neuroprotective strategy. Also the role of gene reprogramming and mitochondrial biogenesis involved in the preconditioning-mediated neuroprotective events will be highlighted. Preconditioning may represent a promising therapeutic weapon to combat neurodegeneration.

Profile of idiopathic parkinson's disease in Moroccan patients

Objective

To characterize clinical aspects of Idiopathic Parkinson’s disease from a movement disorders consultation in University Hospital of Rabat.

Methods

Retrospective review of medical records of 117 patients with diagnosis of Idiopathic Parkinson’s disease seen in our outpatient clinic from 2006 to 2011.

Results

Mean age was 64 ± 10 years with predominance of men (61.5%). Mean age at disease onset was 57 ± 11 years. Early onset Parkinson’s Disease was recorded in 12.8%. The median duration of disease was 5 years. Initial symptom appeared on the right side in 56.5%. Tremor presentation was the most frequent (40.2%). Symptom severity was mild to moderate in 80% of cases (UPDRS < 30). Forty four per cent of patients were receiving both Dopamine Agonists and Levodopa and in 69% of cases Levodopa was introduced within the first year following onset. The mean Levodopa Equivalent Doses (LED) was 667 ± 446 mg/day. Motor complications were found in 42% with motor fluctuations in 28.7% and ²dyskinesias in 26.7%. Non motor complications are represented mainly by autonomic disorders (44%). There were no differences in the clinical presentation related to the age at onset. Age of onset < 45 and LED > 600 mg are identified as risk factors for motor fluctuations whereas duration of Levodopa treatment is a risk factor of dyskinesias.

Conclusion

Our patients are younger compared to most series with high prevalence of early onset forms. In the majority of cases, Levodopa was introduced within the first year following onset which expose patients to dyskinesias early in the course of the disease.

A matter of motion or an emotional matter? Management of depression in Parkinson’s disease

Depression is one of the most frequent comorbidities occurring in Parkinson's disease, affecting up to 50% of patients. Depression is associated with severe negative symptoms and has been shown to contribute to an increased rate of decline of both cognitive and motor function, profoundly impacting on the patient's quality of life. The symptoms of depression overlap with the motor features of Parkinson's disease, making detection difficult. Moreover, the lack of specialized screening tools means that depression remains undiagnosed and untreated in a high percentage of patients. However, depression in Parkinson's disease, when identified early, can be effectively treated with a variety of antidepressant medications, improving quality of life and preserving daily function. The focus of this review is to provide an overview of current knowledge regarding depression in Parkinson's disease, followed by a practical discussion addressing the issues of the detection, diagnosis and treatment.

Neural and behavioral substrates of subtypes of Parkinson's disease

Parkinson’s disease (PD) is a neurological disorder, associated with rigidity, bradykinesia, and resting tremor, among other motor symptoms. In addition, patients with PD also show cognitive and psychiatric dysfunction, including dementia, mild cognitive impairment (MCI), depression, hallucinations, among others. Interestingly, the occurrence of these symptoms—motor, cognitive, and psychiatric—vary among individuals, such that a subgroup of PD patients might show some of the symptoms, but another subgroup does not. This has prompted neurologists and scientists to subtype PD patients depending on the severity of symptoms they show. Neural studies have also mapped different motor, cognitive, and psychiatric symptoms in PD to different brain networks. In this review, we discuss the neural and behavioral substrates of most common subtypes of PD patients, that are related to the occurrence of: (a) resting tremor (vs. nontremor-dominant); (b) MCI; (c) dementia; (d) impulse control disorders (ICD); (e) depression; and/or (f) hallucinations. We end by discussing the relationship among subtypes of PD subgroups, and the relationship among motor, cognitive, psychiatric factors in PD.

Treatment of dementia with lewy bodies

OPINION STATEMENT

Dementia with Lewy bodies (DLB) is a multisystem disorder with diverse disease expression. A treatment regime restricted to the cognitive aspects of the disease does no favor to patients. Instead, patients should be educated to recognize the symptoms of this multisystem involvement. There are no treatments that slow the progression of disease, but symptomatic treatments can be effective. When thinking about treatment, we find it useful to divide the symptoms and signs into five categories: (a) cognitive features, (b) neuropsychiatric features, (c) motor dysfunction, (d) autonomic dysfunction, and (e) sleep dysfunction. Clinicians, funding bodies and industry are increasingly recognizing the importance of this common and debilitating disease.

Dopaminergic modulation of memory and affective processing in Parkinson depression

Depression is common in Parkinson's disease and is associated with cognitive impairment. Dopaminergic medications are effective in treating the motor symptoms of Parkinson's disease; however, little is known regarding the effects of dopaminergic pharmacotherapy on cognitive function in depressed Parkinson patients. This study examines the neuropsychological effects of dopaminergic pharmacotherapy in Parkinsonian depression. We compared cognitive function in depressed and non-depressed Parkinson patients at two time-points: following overnight withdrawal and after the usual morning regimen of dopaminergic medications. A total of 28 non-demented, right-handed patients with mild to moderate idiopathic Parkinson's disease participated. Ten of these patients were depressed according to DSM IV criteria. Results revealed a statistically significant interaction between depression and medication status on three measures of verbal memory and a facial affect naming task. In all cases, depressed Parkinson's patients performed significantly more poorly while on dopaminergic medication than while off. The opposite pattern emerged for the non-depressed Parkinson's group. The administration of dopaminergic medication to depressed Parkinson patients may carry unintended risks.

Regional homogeneity abnormalities affected by depressive symptoms in migraine patients without aura: a resting state study

Background

Bidirectional relationship between migraine and depression suggests that there might be some etiological risk factors shared. However, few studies investigated resting state abnormalities affected by depressive symptoms in migraine patients without aura (MWoA).

Materials and Methods

According to their self-rating depression scale (SDS) score, MWoA were divided into twenty in the SDS (+) (SDS > 49) group and 20 in the SDS (−) (SDS ≤ 49) group. Regional homogeneity (ReHo) method were employed to assess local features of spontaneous brain activity between 1) all MWoA and healthy controls, 2) each subgroup and healthy controls, and 3) SDS (−) group and SDS (+) group.

Results

Compared with healthy controls, decreased ReHo in similar regions were shown in the MWoA group and subgroups. It is noteworthy that the caudate showed increased ReHo in the SDS (−) group compared with healthy controls and the SDS (+) group. Moreover, the average ReHo values of the caudate in SDS (−) group were significantly positively correlated with duration of migraine.

Conclusions

Our results suggested that ReHo patterns in migraine patients may be affected by depressive symptoms and serve as a biomarker to reflect depression severity in MWoA.

Cytokines as biomarkers in depressive disorder: current standing and prospects

The frequently observed co-occurrence of depressive disorders and inflammatory diseases suggests a close connection between the nervous and the immune systems. Increased pro-inflammatory and type 1 cytokines, such as interleukin (IL)-1, tumour necrosis factor (TNF)-α and interferon (IFN)-γ, appear to be an important link. Cytokines are synthesized by immune cells in the blood and peripheral tissues and by glial cells in the central nervous system (CNS). Evidence suggests that the blood-brain barrier (BBB) is permeable to cytokines and immune cells, and that afferent nerves, e.g. the vagus nerve, mediate the communication between peripheral inflammatory processes and CNS. Cytokines such as IL-1ß, TNF-α and IFN-γ seem to contribute to the pathophysiology of depression by activating monoamine reuptake, stimulating the hypothalamic-pituitary-adrenocortical (HPA) axis and decreasing production of serotonin due to increased activity of indolamine-2,3-dioxygenase (IDO). However, critical appraisal of these hypotheses is required, because cytokine elevation is not specific to depression. Moreover, several effective antidepressants such as amitriptyline and mirtazapine have been shown to increase cytokine production. When applying immunomodulatory therapies, these drugs may increase the risk of specific side effects such as infections or interact with antidepressant drugs on important functions of the body such as the coagulation system.

Depression in Parkinson's disease: identification and management

Depression is a common psychiatric comorbidity in Parkinson's disease (PD) and contributes to significant impairments in cognitive, functional, motor, and social performance. This results in reduced quality of life, higher levels of care dependency, and increased caregiver burden. When treating depression, it is important to ensure that the patient's response to treatment will be adequately monitored. This can be accomplished in neurology or primary care settings, or in clinical settings with interdisciplinary treatment teams. Mental health services should be engaged early as a component of ongoing comprehensive care. This article reviews a general approach to treating the pharmacotherapy of depression in PD. Ultimately, clinicians should rely on empiric assessments of known risks and putative benefits to guide treatment decisions and should include a targeted and individualized multimodal approach that utilizes psychotherapeutic interventions along with pharmacologic therapies.

A non-comparative assessment of tolerability and efficacy of duloxetine in the treatment of depressed patients with Parkinson's disease

OBJECTIVE

Depression is a comorbidity affecting quality of life (QoL) in patients with Parkinson's disease (PD) and requires appropriate treatment. This study evaluated the tolerability, safety, and efficacy of duloxetine 60 mg once daily for 12 weeks in PD patients with major depressive disorder (MDD).

RESEARCH AND DESIGN METHODS

Non-comparative, open-label, multi-center study.

MAIN OUTCOME MEASURES

Tolerability was evaluated by discontinuation rate (acceptable if ≤ 19%) due to treatment-emergent adverse events (TEAEs) and motor symptoms (UPDRS). Safety measures were TEAEs, the UKU side effect rating scale, vital signs, weight, laboratory tests, and ECG. Efficacy measures included HAMD-17, BDI, CGI-S, PGI-I, and pain VAS. QoL was measured by PDQ-39.

RESULTS

Of the 151 patients enrolled, 8.6% (95% upper CI: 13.3%) discontinued the study due to TEAEs. Worsening in PD-related tremor and rigidity was not observed, activities of daily living significantly improved and UKU subscales progressively decreased. Clinically significant abnormalities in laboratory findings were limited to four cases of hypercholesterolemia and one increase of total bilirubin, CPK, and fasting glucose. Blood pressure, weight, and ECG did not change from baseline. HAMD-17 and PDQ-39 total score and individual domains, BDI, CGI-S, and PGI-I total scores significantly improved.

CONCLUSIONS

Duloxetine seems well tolerated and likely effective in the treatment of depression associated with PD, with no detrimental effects in PD signs and symptoms.

Motor symptoms at onset of Parkinson disease and risk for cognitive impairment and depression

OBJECTIVE

To determine whether side and type of initial motor symptoms in Parkinson disease (PD) predict risk for later development of cognitive impairment or depressive symptoms.

METHODS

We recruited 124 non-demented patients with PD to participate in a cohort study of cognitive function and depressive symptoms that used validated neuropsychological tests and a depressive symptom inventory. We first reviewed the patients' charts to determine their initial motor symptom and side of onset, and then classified the patients into 4 groups: right-sided onset tremor, right-sided onset bradykinesia/rigidity, left-sided onset tremor, and left-sided onset bradykinesia/rigidity. We excluded patients with bilateral symptom onset. We used analysis of variance on neuropsychological test performance and depressive symptoms to determine whether group classification affected risk of cognitive impairment or depressive symptoms. We controlled our analyses for disease duration and motor severity as measured by the Unified Parkinson Disease Rating Scale Part III motor score.

RESULTS

There were no differences in any cognitive measure by side and type of initial motor symptoms. The right-sided onset tremor group had the lowest depressive symptom scores, and no patient in any group reported severe depressive symptoms.

CONCLUSIONS

Our findings suggest that patterns of nigral cell loss correlating to the initial side and type of motor symptoms in PD are not related to the risk of later cognitive impairment. By contrast, patients with right-sided onset of tremor seem to have a lower risk of depressive symptoms than patients with other presentations.

The pharmacologic management of depression in Parkinson's disease

Depression in Parkinson's disease (PD) is common, and it appears to worsen the motor and cognitive progression of the disease, and limits the patient's quality of life. In this paper, we review the pharmacotherapy of depression in people with PD. We find that evidence is sparse when it comes to this patient population. There is some evidence that older tricyclic antidepressants (nortriptyline and desipramine) may be effective in this population. There is also growing evidence that newer antidepressants like paroxetine and venlafaxine may be effective. We will also review a number of other promising medication treatments. What is apparent is the need for more research identifying the most effective medications for treating depression in this population. We provide recommendations that fall in line with current evidence-based practice for managing depression in the general population. Also, we suggest that collaborative models of depression care may be a promising approach to support the identification and effective treatment of those with PD also suffering from depressive disorders.

Components of depression in Parkinson disease

Depression is a clinically heterogeneous disorder common in Parkinson disease (PD). The goal of this study was to characterize PD depression in terms of components, including negative affect, apathy, and anhedonia. Ninety-five, nondemented individuals with idiopathic PD underwent a diagnostic interview and psychological battery. Twenty-seven patients (28%) met Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition [DSM-IV]) criteria for a current depressive episode. The best-fitting confirmatory factor analysis model had 3 factors (negative affect, apathy, and anhedonia). Apathy loaded most strongly onto a second-order factor representing global psychological disturbance. All factors are uniquely associated with depression status. Negative affect exhibited the strongest relationship. Psychological disturbance in PD is heterogeneous and can produce symptoms of apathy, anhedonia, and negative affect. Apathy appears to be the core neuropsychiatric feature of PD, whereas negative affect (eg, dysphoria) seems to be most pathognomonic of depression. Future studies should examine the specific neural correlates and treatment response patterns unique to these 3 components.

Executive function in Parkinson's disease: contributions of the dorsal frontostriatal pathways to action and motivation

Disruption of the dorsal frontostriatal pathways in Parkinson's disease (PD) is associated with impairments in motivation, as well as in executive function. The goal of this study was to investigate whether these impairments are related and, if so, whether the disruption of frontostriatal pathways compromises the ability to process the motivational aspects of feedback in such tasks. In Experiment 1, informative feedback improved the performance of young, healthy participants in a task-switching paradigm. This task-switching paradigm was then used in Experiment 2 to test whether feedback would improve the performance of 17 PD patients and age-matched controls. The PD group benefitted from feedback to the same degree as control participants; however, depression scores on the Beck Depression Inventory were significantly related to feedback usage, especially when response selection demands were high. Regardless of feedback, PD patients were more impaired when response demands were high than in an equally difficult condition with low action demands. These results suggest that response selection is a core impairment of insufficient dopamine to the dorsal frontal striatal pathways.

Emotional state affects gait initiation in individuals with Parkinson's disease

The purpose of the present study was to determine the impact of manipulating emotional state on gait initiation in persons with Parkinson's disease (PD) and healthy older adults. Following the presentation of pictures that are known to elicit specific emotional responses, participants initiated gait and continued to walk for several steps at their normal pace. Reaction time, the displacement and velocity of the center of pressure (COP) trajectory during the preparatory postural adjustments, and length and velocity of the first two steps were measured. Analysis of the gait initiation measures revealed that exposure to (1) threatening pictures, relative to all other pictures, speeded the initiation of gait for PD patients and healthy older adults; (2) approach-oriented emotional pictures (erotic and happy people), relative to withdrawal-oriented pictures, facilitated the anticipatory postural adjustments of gait initiation for PD patients and healthy older adults, as evidenced by greater displacement and velocity of the COP movement; and (3) emotional pictures modulated gait initiation parameters in PD patients to the same degree as in healthy older adults. Collectively, these findings hold significant implications for understanding the circuitry underlying the manner by which emotions modulate movement and for the development of emotion-based interventions designed to maximize improvements in gait initiation for individuals with PD.

A comparison of nine scales to detect depression in Parkinson disease: which scale to use?

OBJECTIVE

The Methods of Optimal Depression Detection in Parkinson's Disease (MOOD-PD) study compared the psychometric properties of 9 depression scales to provide guidance on scale selection in Parkinson disease (PD).

METHODS

Patients with PD (n = 229) from community-based neurology practices completed 6 self-report scales (Beck Depression Inventory [BDI]-II, Center for Epidemiologic Studies Depression Rating Scale-Revised [CESD-R], 30-item Geriatric Depression Scale [GDS-30], Inventory of Depressive Symptoms-Patient [IDS-SR], Patient Health Questionnaire-9 [PHQ-9], and Unified Parkinson's Disease Rating Scale [UPDRS]-Part I) and were administered 3 clinician-rated scales (17-item Hamilton Depression Rating Scale [HAM-D-17], Inventory of Depressive Symptoms-Clinician [IDS-C], and Montgomery-Åsberg Depression Rating Scale [MADRS] and a psychiatric interview. DSM-IV-TR diagnoses were established by an expert panel blinded to the self-reported rating scale data. Receiver operating characteristic curves were used to estimate the area under the curve (AUC) of each scale.

RESULTS

All scales performed better than chance (AUC 0.75-0.85). Sensitivity ranged from 0.66 to 0.85 and specificity ranged from 0.60 to 0.88. The UPDRS Depression item had a smaller AUC than the BDI-II, HAM-D-17, IDS-C, and MADRS. The CESD-R also had a smaller AUC than the MADRS. The remaining AUCs were statistically similar.

CONCLUSIONS

The GDS-30 may be the most efficient depression screening scale to use in PD because of its brevity, favorable psychometric properties, and lack of copyright protection. However, all scales studied, except for the UPDRS Depression, are valid screening tools when PD-specific cutoff scores are used.

Effects of depression and social support on comprehension and recall of informed consent information among Parkinson disease patients and their caregivers

OBJECTIVE

Relatively little attention has focused on the impact of psychiatric conditions on human subjects' comprehension of consent information. The purpose of this randomized study was to determine whether depression affects comprehension and recall of informed consent information among persons with Parkinson's disease and their caregivers and to evaluate the effects of support on comprehension and recall during the consent process.

METHOD

Comprehension and recall of information were assessed using a modified version of the Modified Quality of Informed Consent Questionnaire, taken 1 week and 1 month later, and scored using a consensus-based algorithm. Participants also completed the Center for Epidemiologic Studies Depression Scale. Data analyses were conducted on 129 patients and caregivers (t-tests, Fisher's exact tests, and ANCOVAs).

RESULTS

T-tests showed no significant differences in comprehension and recall between depressed and nondepressed participants at 1 week and 1 month. However, ANCOVA showed patients with a support person present had significantly higher comprehension and recall at 1 week but not at 1 month compared with controls. Caregivers present with a patient had lower comprehension/recall than those without a patient present (p = 0.02).

CONCLUSIONS

Having a support person present during the informed consent process helps depressed PD patients better retain information in the short-term, but effects diminish over the long-term. Implications for interventions will be discussed.

Emotional dysfunction in Parkinson's disease

In addition to motor symptomatology, idiopathic Parkinson’s disease is characterized by emotional dysfunction. Depression affects some 30 to 40 percent of Parkinson patients and other psychiatric co-morbidities include anxiety and apathy. Neuropsychological and neuroimaging studies of emotional dysfunction in Parkinson patients suggest abnormalities involving mesolimbic and mesocortical dopaminergic pathways. There is also evidence suggesting that the interaction between serotonin and dopamine systems is important in the understanding and treatment of mood disorders in Parkinson’s disease. In this review we discuss the neuropsychiatric abnormalities that accompany Parkinson's disease and describe their neuropsychological, neuropharmacologic, and neuroimaging concomitants.

Depressive symptoms in Parkinson disease: degree of association and rate of agreement of clinician-based and self-report measures

Depression in Parkinson disease (PD) is associated with faster disease progression, lower activities of daily living, and more severe cognitive impairment. Even mild symptoms of depression may impact outcomes in patients with PD. Nevertheless, a low rate of agreement has been reported between patient and clinician ratings of depression, suggesting that clinicians may underestimate depression in patients with PD. However, to accurately compare the rates of agreement, comparable estimates are needed so that patient and clinician ratings have similar meaning (eg, mild, moderate, severe, etc). The purpose of this study was to examine this question by investigating the degree of association and rate of agreement of levels of symptom severity among self-report and clinician ratings using established cutoffs that correspond to more comparable estimates of these levels for both patient and clinician. Our findings suggest that patient's self-report of depressive symptoms was significantly correlated with clinician-based report irrespective of the stage of disease. Moreover, patients demonstrated a 72% rate of agreement with clinicians in classifying symptoms as asymptomatic, mildly symptomatic, or fully symptomatic, a rate significantly higher than the rate of 35% previously reported. This difference in rate of agreement may be accounted for using varying criteria for severity levels across the studies. Findings suggest that clinician and patient reports show a high rate of agreement across a range of depressive symptoms and that self-report measures may provide a relatively efficient means of detecting depressive symptoms especially if patients are disinclined to initiate their report.

Prevalence of depression in Parkinson's disease: effects of disease stage, motor subtype and gender

Depression is one of the most common non-motor symptoms of Parkinson's disease (PD) with a large negative impact on the quality of life. Factors such as disease stage, subtype of PD and gender might play an important role in the prevalence of depression, but a large study investigating all these factors in a within-subject design is lacking. Therefore we studied a homogeneous group of 256 Dutch PD patients (60% men, mean age=65.12 (±9.6) years). In total, 36.3% of the subjects had a BDI-score indicative for a minor depression, while 12.9% had a major depression. Notably, only 8.6% of the minor depressed patients and 30.3% of the major depressed patients were taking antidepressants. A higher prevalence of depression was observed in the later stages of the disease. However, this finding was absent in a smaller subsample after correction for cognitive impairment. Our data did not show a difference in the prevalence of depression between the motor subtypes and showed a trend towards higher prevalence of depression in the tremor dominant group. There was no significant difference in the prevalence of depression between men and women. We will discuss the relevance of these results in relation to the findings of other studies.

Factors associated with depression in Parkinson's disease

BACKGROUND

Depression is common in Parkinson's disease (PD) and contributes significantly to a reduced quality of life in PD patients. The determinants of depression in PD are complex and poorly understood. We investigated the factors associated with depression in PD.

METHODS

PD patients were recruited from Neurology clinics. A validated method was used to screen for a lifetime history of depression. 'Depressed' patients were identified by a score of >6 in the Geriatric Depression Scale (GDS-15) or by having had prescribed treatment for depression. 'Never depressed' patients were recognised by a score of <5 in the GDS-15 with no signs of a history of depression. A newly developed and validated questionnaire was used to collect other information.

RESULTS

Depression was identified in 66% of the 639 PD patients who met the inclusion criteria. Depression was associated with an increased severity of illness as evidenced by higher Unified PD Rating Scale scores and a higher Hoehn and Yahr stage. Other clinical factors associated with disease severity were also more frequently observed in depressed patients. Similar to findings in non-PD samples, depressed PD patients were more likely to have a lower education level, a history of smoking and to regularly use non-aspirin based NSAIDs or analgesics. Comorbidities such as anxiety, memory problems, hallucinations, sleep disturbances and postural hypotension were more common in depressed PD patients.

LIMITATIONS

To avoid patient exhaustion of over-surveying, some factors within the psychological domain were not examined.

CONCLUSION

Our results provide a focus for future intervention strategies.

The role of cognitive-behavioural therapy for patients with depression in Parkinson's disease

Depression is a common complication of Parkinson's disease (PD) with considerable impact on patients' quality of life. However, at present the most appropriate treatment approach is unclear. There are limited data on antidepressant medications in PD-associated depression (dPD) and those available suggest limited efficacy and tolerability of these drugs. Cognitive behavioural therapy (CBT) has been shown to be an effective treatment of depressive disorders. Treatment of dPD with CBT may pose particular challenges, including possible different pathophysiology, physical and mental comorbidities, and barriers to treatment through disability, which do not allow simple transfer of these results to patients with dPD. However, a number of case reports, case series, and small pilot studies suggest that this is a promising treatment for patients with PD. We here summarise the published evidence on this treatment in dPD.

Treatment of depressive symptoms in Parkinson's disease

Significant depressive disorders are present in approximately 30-40% of patients with Parkinson's disease (PD). Depressive symptoms are correlated with poor health-related quality-of-life (HRQoL) scores, and are the major determinant of HRQoL. Studies that have evaluated pharmacotherapy for depressive symptoms in PD have shown that there is substantial variability in outcomes. Recently, two double-blind, placebo-controlled studies showed the superiority of nortriptyline and desipramine versus placebo and selective serotonin reuptake inhibitors. The antidepressant effects of dopamine agonists have been explored mainly in open and non-controlled studies. In a 14-week randomized trial comparing pramipexole with sertraline in depressed patients without motor complications, the Hamilton Depression Rating Scale score decreased in both groups; however, in the pramipexole group, the proportion of patients who recovered was significantly higher. Recently, in the first 12-week double-blind placebo-controlled clinical trial in PD patients without motor fluctuations on stable levodopa treatment, pramipexole reduced depressive symptoms as measured by Beck Depression Inventory score, with a significant difference in efficacy in favour of pramipexole. These data suggest that pramipexole might represent an alternative to antidepressant drugs to treat depressive symptoms in PD without adding the risk of antidepressant adverse events, and avoid polypharmacy.

Electroconvulsive therapy alters dopamine signaling in the striatum of non-human primates

Electroconvulsive therapy (ECT) is one of the most effective therapies for depression and has beneficial motor effects in parkinsonian patients. However, little is known about the mechanisms of therapeutic action of ECT for either condition. The aim of this work was to explore the impact of ECT on dopaminergic function in the striatum of non-human primates. Rhesus monkeys underwent a course of six ECT treatments under a human clinical protocol. Longitudinal effects on the dopaminergic nigrostriatal system were studied over 6 weeks using the in vivo capabilities of positron emission tomography (PET). PET scans were performed prior to the onset of ECT treatments and at 24-48 h, 8-10 days, and 6 weeks after the final ECT treatment. Early increases in dopamine transporter and vesicular monoamine transporter 2 binding returned to baseline levels by 6 weeks post-ECT. Transient increases in D1 receptor binding were also observed, whereas the binding potential to D2 receptors was unaltered. The increase in dopaminergic neurotransmission suggested by our results may account in part for the therapeutic effect of ECT in mood disorders and Parkinson's disease.

Social support and psychological outcome in people with Parkinson's disease: Evidence for a specific pattern of associations

OBJECTIVE

The aim of this study was to explore the relationship between social support and psychological functioning in people with Parkinson's disease.

METHOD

34 participants with idiopathic Parkinson's disease completed a comprehensive range of social support assessments and measures of depression, anxiety, stress, general psychological distress and positive affect.

RESULTS

A clear pattern of relationships emerged, with the less satisfaction with social support, the higher the depression, anxiety and stress scores. Conversely, positive affect was related to more quantitative assessments of social support, such as the number of close relationships.

CONCLUSION

The relationship between social support and psychological outcome in people with PD is complex. Furthermore, the complexity of this relationship should be addressed in any therapeutic attempts to relieve psychological distress and promote happiness.

Nonmotor symptoms in Parkinson’s disease: the dark side of the moon

Nonmotor symptoms may appear during the course of Parkinson’s disease, complicating the advanced phase in particular, but are also common in the premotor phase of Parkinson’s disease. The appearance of nonmotor manifestations represents a milestone, determining a worse prognosis and lower quality of life; however, they are often misdiagnosed and untreated. The spectrum of nonmotor symptoms encompasses mood disorders, psychosis, dementia, sleep disorders, impulse-control disorders and autonomic dysfunctions. This article describes these nonmotor symptoms and their management.

Pattern of depressive symptoms in Parkinson's disease

BACKGROUND

Depressive symptoms are common in Parkinson's disease (PD); however, it is unclear whether there are specific depressive symptom patterns in patients with PD and comorbid depression (dPD).

OBJECTIVE

The goal of this study is to examine the frequency and correlates of specific depressive symptoms in PD.

METHOD

A sample of 158 individuals with PD completed the self-rated Harvard Department of Psychiatry/National Depression Screening Day Scale (HANDS). By multiple-regression analysis, the authors examined the association between HANDS total and subscale scores and various demographic variables.

RESULTS

The frequency of depression was 37% (N=58). Patients with a history of depression before PD had significantly more serious depression than those who had no such history. Of those who were more depressed, the most common symptoms of depression endorsed were low energy, difficulty with concentration/making decisions, feeling blue, feeling hopeless, and having poor sleep.

CONCLUSION

There is a relatively high prevalence of dPD. Items on the HANDS that discriminated best between depressed and nondepressed subjects with PD included feeling blue, feeling hopeless, feeling worthless, lack of interest, and self-blame. It remains to be defined whether dPD should be understood primarily as a psychological reaction to a physical disability or perceived impending one, or as a direct expression of the neuropathology of PD.

Brain volume abnormalities in major depressive disorder: a meta-analysis of magnetic resonance imaging studies

OBJECTIVE

So far, there have been no attempts to integrate the growing number of all brain volumetric magnetic resonance imaging studies in depression. In this comprehensive meta-analysis the magnitude and extent of brain volume differences between 2,418 patients with major depressive disorder and 1,974 healthy individuals from 64 studies was determined.

METHODS

A systematic research was conducted for volumetric magnetic resonance imaging studies of patients with major depressive disorder in relation to healthy control subjects. Studies had to report sufficient data for computation of effect sizes. For each study, the Cohen's d was calculated. All analyses were performed using the random effects model. Additionally, meta-regression analyses were done to explore the effects of potential sources of heterogeneity.

RESULTS

Patients showed large volume reductions in frontal regions, especially in the anterior cingulate and orbitofrontal cortex with smaller reductions in the prefrontal cortex. The hippocampus, the putamen and caudate nucleus showed moderate volume reductions.

CONCLUSIONS

This is the first comprehensive meta-analysis in major depressive disorder demonstrating structural brain abnormalities, particularly in those brain areas that are involved in emotion processing and stress-regulation.

The use of selective serotonin reuptake inhibitors in elderly patients

Depression is common among the elderly, and several factors need to be taken into account in selecting the appropriate antidepressant in this age group. Various physiologic changes occur in individuals as they age, potentially leading to changes in the pharmacodynamic and pharmacokinetic properties of drugs in elderly individuals. The efficacy of various medications, their side-effect profiles, and the potential for drug-drug interactions may differ in older patients compared to younger ones. The selective serotonin reuptake inhibitors (SSRIs), which are seen as being among the first-line agents for treatment of depression in elderly patients, have been shown to be effective but carry with them side effects and drug-drug interactions that warrant special attention when these medications are prescribed to older individuals. This review focuses on the pharmacology of SSRIs in elderly patients and on practical issues related to using these medications.

Brainstem pathology and non-motor symptoms in PD

Parkinson's disease (PD) is considered a multisystem disorder involving dopaminergic, noradrenergic, serotoninergic, and cholinergic systems, characterized by motor and non-motor symptoms. The causes of the non-motor symptoms in PD are multifactorial and unlikely to be explained by single lesions. However, several evidence link them to damage of specific brainstem nuclei. Numerous brainstem nuclei are engaged in fundamental homeostatic mechanisms, including gastrointestinal regulation, pain perception, mood control, and sleep-wake cycles. In addition, these nuclei are locally interconnected in a complex manner and are subject to supraspinal control. The objective of this review is to provide a better overview of the current knowledge about the consequences of the involvement of specific brainstem nuclei to the most prevalent non-motor symptoms occurring in PD. The multidisciplinary efforts of research directed to these non-nigral brainstem nuclei, in addition to the topographical and chronological spread of the disease - especially in the prodromal stages of PD, are discussed.

Suicidal ideation in Parkinson's disease

OBJECTIVE

To assess the frequency of suicidal ideation and suicide attempts in patients with Parkinson's disease.

METHODS

The Mini International Neuropsychiatric Interview (MINI), Beck Depression Inventory (BDI), and Hamilton Rating Scale for Depression (HAM-D) were administered to 90 consecutive, non-demented Parkinson's disease patients. They were also submitted to a complete neurologic examination which included brief cognitive batteries, the Mini Mental Status Exam, and Frontal Assessment Battery. We analyzed the scores of the section of the MINI related to the risk of suicide as well as the specific questions of BDI and HAM-D concerning suicidal ideation.

RESULTS

No patient had ever attempted suicide. According to MINI, suicidal ideation was present in 13 patients (14.4%) with Parkinson's disease. All instruments assessed the risk of suicide in a similar way. Suicidal ideation was associated only with lower age (P=.022), lower age of Parkinson's disease onset (P=.021), panic disorder (P=.004), social anxiety disorder (P=.007), and major depression (P<.001). Logistic regression analysis indicated that major depression was the main predictor of suicidal ideation.

CONCLUSION

Suicide attempts seem to be uncommon in Parkinson's disease, despite the fact that the rates of suicidal ideation are possibly elevated. Depression seems to be the most important predictor of suicidal ideation in Parkinson's disease.

Validity of the Cornell scale for depression in dementia in Parkinson's disease with and without cognitive impairment

Valid tools are needed to assess depression across the spectrum of cognitive impairment in Parkinson's disease (PD). The validity of the Cornell scale for depression in dementia (CSDD) was tested in a PD sample with a range of cognitive impairment. Psychiatric diagnoses were established according to DSM-IV-TR. Receiver operating characteristic curves tested the discriminant validity of the CSDD compared to the clinical diagnoses of major and minor depression. The curve for symptomatic depression had an area under the curve of 0.82. For the cut-off score >or= 6, sensitivity was 0.83 and specificity was 0.73; for the cut-off score >or= 8, sensitivity was 0.75 and specificity was 0.82. There was no evidence for differential measurement with respect to cognitive impairment or any other demographic or clinical variables. This study suggests that the CSDD is a valid tool for identifying depressive disorders in patients with PD across a spectrum of cognitive impairment.

Telephone-administered cognitive behavioral therapy: a case study of anxiety and depression in Parkinson's disease

Parkinson's disease (PD) is a chronic medical illness with a high incidence of psychiatric comorbidity, specifically depression and anxiety. Research on treatment of such psychiatric complications is scarce. Non-pharmaceutical treatment options are especially attractive. Cognitive behavioral therapy (CBT) is a psychotherapeutic treatment option that has been successful in other chronically medically ill populations with comorbid depression and anxiety. The current research had two aims. The first was to pilot the feasibility of screening and identifying PD patients with symptoms of anxiety and depression in a specialized outpatient clinic. The second aim was to pilot the feasibility of telephone-administered CBT for the treatment of depression and anxiety in persons with PD, which was done through a case series comparing telephone-administered CBT to a Support strategy. A fairly large portion (67.5%) of patients screened in the outpatient clinic were identified as having symptoms of anxiety and/or depression. Results also indicated that CBT delivered via the telephone is a useful approach for targeting psychiatric symptoms in this population. A case example is given to illustrate the clinical considerations associated with delivering therapy via telephone to persons with PD.

Suicidal and death ideation in Parkinson's disease

Parkinson's disease (PD) is a chronic, disabling illness affecting primarily the elderly and is associated with a high prevalence of depression. Although these are known risk factors for suicidal and death ideation, little is known about the prevalence and correlates of such ideation in PD. A convenience sample of 116 outpatients with idiopathic PD at two movement disorders centers were administered a modified Paykel Scale for suicidal and death ideation, as well as an extensive psychiatric, neuropsychological, and neurological battery. Univariate and multivariate logistic regression models were used to determine the correlates of suicidal or death ideation. Current death ideation (28%) or suicide ideation (11%) were present in 30% of the sample, and 4% had a lifetime suicide attempt. On univariate logistic regression analysis, increasing severity of depression (odds ratio = 2.92, 95% CI 2.01-4.24, P < 0.001), impulse control disorder (ICD) behaviors sometime during PD (odds ratio = 6.08, 95% CI 1.90-19.49, P = 0.002), and psychosis (odds ratio = 2.45, 95% CI 1.05-5.69, P = 0.04) were associated with either ideation. On multivariate logistic regression analysis, only increasing severity of depressive symptoms (odds ratio = 2.76, 95% CI 1.88-4.07, P < 0.001) predicted suicidal or death ideation. In conclusion, active suicidal or death ideation occurs in up to one-third of PD patients. Comorbid psychiatric disorders, more than PD-related disease variables, are associated with this ideation, highlighting the need for a comprehensive approach to the clinical care of PD patients.

Startle reflex hyporeactivity in Parkinson's disease: an emotion-specific or arousal-modulated deficit?

We previously reported that patients with Parkinson's disease (PD) demonstrate reduced psychophysiologic reactivity to unpleasant pictures as indexed by diminished startle eyeblink magnitude [Bowers, D., Miller, K., Bosch, W., Gokcay, D., Pedraza, O., Springer, U., et al. (2006). Faces of emotion in Parkinsons disease: Micro-expressivity and bradykinesia during voluntary facial expressions. Journal of the International Neuropsychological Society, 12(6), 765-773; Bowers, D., Miller, K., Mikos, A., Kirsch-Darrow, L., Springer, U., Fernandez, H., et al. (2006). Startling facts about emotion in Parkinson's disease: Blunted reactivity to aversive stimuli. Brain, 129(Pt 12), 3356-3365]. In the present study, we tested the hypothesis that this hyporeactivity was primarily driven by diminished reactivity to fear-eliciting stimuli as opposed to other types of aversive pictures. This hypothesis was based on previous evidence suggesting amygdalar abnormalities in PD patients, coupled with the known role of the amygdala in fear processing. To test this hypothesis, 24 patients with Parkinson's disease and 24 controls viewed standardized sets of emotional pictures that depicted fear, disgust (mutilations, contaminations), pleasant, and neutral contents. Startle eyeblinks were elicited while subjects viewed these emotional pictures. Results did not support the hypothesis of a specific emotional reactivity deficit to fear pictures. Instead, the PD patients showed reduced reactivity to mutilation pictures relative to other types of negative pictures in the context of normal subjective ratings. Further analyses revealed that controls displayed a pattern of increased startle eyeblink magnitude for "high arousal" versus "low arousal" negative pictures, regardless of picture category, whereas startle eyeblink magnitude in the PD group did not vary by arousal level. These results suggest that previous findings of decreased aversion-modulated startle is driven by reduced reactivity to highly arousing negative stimuli rather than to a specific category (i.e., fear or disgust) of emotion stimuli.

Memory, mood, dopamine, and serotonin in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned mouse model of basal ganglia injury

The 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mouse serves as a model of basal ganglia injury and Parkinson's disease. The present study investigated the effects of MPTP-induced lesioning on associative memory, conditioned fear, and affective behavior. Male C57BL/6 mice were administered saline or MPTP and separate groups were evaluated at either 7 or 30 days post-lesioning. In the social transmission of food preference test, mice showed a significant decrease in preference for familiar food 30 days post-MPTP compared to controls. Mice at both 7 and 30 days post-MPTP lesioning had increased fear extinction compared to controls. High Performance Liquid Chromatography analysis of tissues homogenates showed dopamine and serotonin were depleted in the striatum, frontal cortex, and amygdala. No changes in anxiety or depression were detected by the tail suspension, sucrose preference, light-dark preference, or hole-board tests. In conclusion, acute MPTP lesioning regimen in mice causes impairments in associative memory and conditioned fear, no mood changes, and depletion of dopamine and serotonin throughout the brain.

The effects of antidepressants in Parkinson's disease: a meta-analysis

This study explored the therapeutic effect of antidepressants in Parkinson's disease (PD) using a meta-analysis. Altogether, 24 placebo-controlled trials qualified for inclusion and revealed that tricyclic antidepressants (TCAs) had a greater antidepressant effect relative to selective serotonin reuptake inhibitors (SSRIs), Qb(1) = 8.87, p < .01, and the mono-amine-oxidase inhibitor, selegiline, Qb(1) = 7.90, p < .01. Whereas TCAs produced a significant side effect profile (odds ratio = 3.07), adverse events were negligible with SSRIs (odds ratio = 1.83) and selegeline (odds ratio = 1.63). Antidepressants can be beneficial for patients with PD. However, the choice of antidepressants needs to take depressive symptomatologies into account while monitoring side effects.

The neuropathological basis for depression in Parkinson's disease

Depression is found in 30-40% of all patients with Parkinson's disease (PD), but its etiology is unclear. Using neuropathology as a signpost for neurotransmitter function, we investigated the prevalence of pathological features found at postmortem and sought to uncover differences between depressed (n=11) and non-depressed (n=9) elderly PD patients. The results indicate a higher prevalence of pathological features in depressed compared to non-depressed PD patients, particularly in catecholamine areas of the brain; the locus coeruleus (neuronal loss: odds ratio=7.2, p=08; gliosis: odds ratio=18.0, p=008); dorsal vagus nerve (gliosis: odds ratio=7.63, p<0.05), and substantia nigra pars compacta (gliosis: odds ratio=2.85, ns). However, neuropathological differences were absent in the dorsal raphe nuclei, amygdala, and cortical regions. Our evidence suggests that depression in PD is related more to catecholaminergic than serotonergic system dysfunction.

Attitudes regarding the etiology and treatment of depression in Parkinson's disease: a qualitative study

Depression in Parkinson's disease (dPD) remains under recognized and under treated. As patients' beliefs may impact the reporting and treatment of depression, this study assessed the opinions of 38 dPD patients, approximately half with a self-reported poor response to antidepressant treatment, regarding the etiology and treatment of their depression using a semi-structured, audio-taped, qualitative interview. About half of the participants listed PD itself as a primary cause for their depressive symptoms, with most in this group citing psychosocial factors rather than PD-related neurobiological factors. Antidepressant therapy, psychotherapy, and self-initiated approaches were noted as preferred treatments for dPD. Many had concerns about antidepressant therapy, listing side-effects and medication dependency most frequently. About half raised concerns about psychotherapy with trust/discomfort, stigma, and transportation issues most frequently mentioned. This preliminary study suggests that many PD patients with clinically significant depressive symptoms attribute their depression to psychosocial factors and endorse nonpharmacologic treatment approaches.