Depression rating scales in Parkinson's disease: critique and recommendations

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.

Cognitive assessment instruments in Parkinson's disease patients undergoing deep brain stimulation

Deep Brain Stimulation (DBS) is a widely used surgical technique in individuals with Parkinson's disease (PD) that can lead to significant reductions in motor symptoms.

Psychosis, apathy, depression and anxiety in Parkinson's disease

Psychiatric symptoms are important non-motor features in PD, which occur at high frequency and have significant impact on health related quality of life. This review concentrates on the prevalence, pathophysiology, diagnosis and treatment of depression, anxiety, apathy and psychosis. The pathophysiology of these disorders is complex, reflecting the widespread brainstem and cortical pathology in PD, with involvement of several neurotransmitters, including dopaminergic, serotonergic, noradrenergic and cholinergic systems. The diagnosis of psychiatric conditions, in particular affective disorders, is challenging because of the overlap of somatic features of psychiatric disorders and underlying movement disorder. The pathogenesis is likely to differ considerably from non-PD patients, and treatments used in general psychiatry services may not be as effective in PD and will require clearer clarification in well-designed clinical studies. Management strategies include adjustment of dopaminergic medication, use of psychotropic treatments and behavioural and psychological approaches. However, the future challenge will be to develop treatments developed specifically for the pathogenesis of these disorders in PD.

Toys and gadgets: construct validity of apathy in Parkinson's disease

Apathy is one of the primary neuropsychiatric signatures in Parkinson's disease, yet little research has addressed the construct validity of two commonly used apathy measures, the Apathy Scale and the Lille Apathy Rating Scale. The authors tested the hypothesis that apathy is associated with reduced initiative/engaged behaviors on a laboratory-based measure of apathy. Support was found for the hypothesis that apathy, as indexed by the Apathy Scale and the Lille Apathy Rating Scale, is associated with reduced initiative/engagement on an experimental measure of apathy in Parkinson's disease patients. These findings provide independent evidence for the construct validity of self-report apathy scales, beyond clinician judgment.

Parkinson's disease

Parkinson's disease (PD) is the most common age-related motoric neurodegenerative disease initially described in the 1800's by James Parkinson as the 'Shaking Palsy'. Loss of the neurotransmitter dopamine was recognized as underlying the pathophysiology of the motor dysfunction; subsequently discovery of dopamine replacement therapies brought substantial symptomatic benefit to PD patients. However, these therapies do not fully treat the clinical syndrome nor do they alter the natural history of this disorder motivating clinicians and researchers to further investigate the clinical phenotype, pathophysiology/pathobiology and etiology of this devastating disease. Although the exact cause of sporadic PD remains enigmatic studies of familial and rare toxicant forms of this disorder have laid the foundation for genome wide explorations and environmental studies. The combination of methodical clinical evaluation, systematic pathological studies and detailed genetic analyses have revealed that PD is a multifaceted disorder with a wide-range of clinical symptoms and pathology that include regions outside the dopamine system. One common thread in PD is the presence of intracytoplasmic inclusions that contain the protein, α-synuclein. The presence of toxic aggregated forms of α-synuclein (e.g., amyloid structures) are purported to be a harbinger of subsequent pathology. In fact, PD is both a cerebral amyloid disease and the most common synucleinopathy, that is, diseases that display accumulations of α-synuclein. Here we present our current understanding of PD etiology, pathology, clinical symptoms and therapeutic approaches with an emphasis on misfolded α-synuclein.

Depressive symptoms among hospitalized patients in Israel

Depressive symptoms are common among hospitalized patients and can indicate more serious problems. This study examined the level of depressive symptoms among patients in one hospital in Jerusalem, the variables related to depression, and the extent to which social workers provided services to those patients. Over 60% of patients reported high levels of depressive symptoms. Levels were higher among Arabs, those with lower income, small social networks, stronger locus of control (powerful others), weaker internal locus of control, and low emotional support from staff. Social workers were in contact with 44% of patients who had high levels of depressive symptoms.

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.

Depression in Parkinson disease--epidemiology, mechanisms and management

Depression occurs in around 35% of patients with Parkinson disease (PD) and is often persistent. Symptoms of depression can be evident in individuals at the time of diagnosis and might develop in the premotor stage of the disease. The underlying mechanisms of depression in PD are not known in detail, but changes in brain structure, signaling by neurotransmitters, and levels of inflammatory and neurotrophic factors are all suggested to contribute to its development. Psychosocial factors and pain could also have roles in depression. Changes in dopaminergic, noradrenergic and serotonergic systems in patients with PD might help to explain the incidence of depression in these individuals. Antidepressants that have dual serotonergic and noradrenergic effects are the drugs of choice for treating depression in PD. However, antiparkinsonian drugs might have beneficial effects not only on the motor symptoms of disease, but also on a patient's mood. Deep brain stimulation can worsen depression in some patients, but a preliminary study has suggested that transcranial magnetic stimulation could improve symptoms of depression. This Review describes the frequency and course of depression in patients with PD. The mechanisms that underlie depression in this disease are also discussed, and the management strategies for these patients are highlighted.

Telephone-based cognitive-behavioral therapy for depression in Parkinson disease

BACKGROUND

Although face-to-face cognitive-behavioral therapy (CBT) was found to be beneficial for the treatment of depression in Parkinson disease (dPD) in a recent randomized-controlled trial, access to care was identified as a critical issue that needs to be addressed in order to improve the management of this nonmotor complication in PD. The purpose of this study was to examine the feasibility and effect of telephone-based CBT for dPD.

METHODS

Twenty-one depressed people with PD participated in a National Institutes of Health-sponsored uncontrolled pilot trial of telephone-based CBT in an academic medical center from October 2009 to February 2011. The Hamilton Depression Rating Scale was the primary outcome. Treatment was provided to people with PD for 10 weeks, modified for delivery over the phone, and supplemented with 4 separate phone-based caregiver educational sessions. Assessments were completed at baseline and 5 (midpoint), 10 (end-of-treatment), and 14 weeks (follow-up) post-enrollment.

RESULTS

Twenty (95%) people with PD completed the study treatment. Phone-based CBT was associated with significant improvements in depression, anxiety, negative thoughts, and coping. Mean Hamilton Depression Rating Scale change from baseline to week 10 was 7.91 points (P < .001, Cohen d = 1.21).

CONCLUSIONS

Telephone-based CBT may be a feasible and helpful approach for treating dPD and warrants further exploration in randomized-controlled trials. Results were comparable to those observed in the few in-person cognitive-behavioral treatment studies for dPD conducted to date.

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.

Apathy and depression: separate factors in Parkinson's disease

The objective of this study was to test the hypothesis that apathy and depression are dissociable in Parkinson disease (PD) by conducting a confirmatory factor analysis (CFA) of items from two commonly used mood scales. A total of 161 non-demented PD patients (age = 64.1; ± 8.4 years) were administered the Apathy Scale and the Beck Depression Inventory-II. Items were hypothesized to load onto four factors: (1) an apathy factor representing loss of motivation, (2) dysphoric mood factor representing sadness and negativity, (3) loss of interest/pleasure factor representing the features common to both apathy and depression, and (4) a somatic factor representing bodily complaints. Results indicated a good fit for the overall CFA model, χ² (128, N = 146) = 194.9; p<.01. RMSEA was .060 (p = .16). The four-factor model was significantly better than all alternative nested models at p < .001, including an overarching single factor model, representing "depression." Results support the concept that apathy and depression are discrete constructs. We suggest a "factor based" scoring of the Apathy Scale and Beck Depression Inventory-II that disentangles symptoms related to apathy, depression, overlapping symptoms, and somatic complaints. Such scoring may be important in providing useful information regarding differential treatment options.

Cognitive-behavioral therapy for depression in Parkinson's disease: a randomized, controlled trial

OBJECTIVE

Despite the negative effects of depression in Parkinson's disease, there is currently no evidence-based standard of care. The purpose of this study was to examine the efficacy of individually administered cognitive-behavioral therapy (CBT), relative to clinical monitoring (with no new treatment), for depression in this medical population.

METHOD

Eighty depressed (based on DSM-IV criteria) patients with Parkinson's disease participated in a randomized, controlled trial of CBT relative to clinical monitoring (1:1 ratio) in an academic medical center from April 2007 to July 2010. All patients continued to maintain stable medication regimens under the care of their personal physicians. The 17-item Hamilton Depression Rating Scale (HAM-D) total score was the primary outcome. CBT was modified to meet the unique needs of the Parkinson's disease population and provided for 10 weeks. Assessments were completed by blind raters at baseline and 5 (midpoint), 10 (end of treatment), and 14 weeks (follow-up evaluation) postrandomization.

RESULTS

The CBT group reported greater reductions in depression (change in HAM-D score) than the clinical monitoring group. At week 10, the mean HAM-D score change was 7.35 for CBT relative to 0.05 for clinical monitoring. CBT was also superior to clinical monitoring on several secondary outcomes (i.e., Beck Depression Inventory scores, anxiety, quality of life, coping, Parkinson's disease symptom ratings). There were more treatment responders in the CBT group than the clinical monitoring group (56% versus 8%, respectively).

CONCLUSIONS

CBT may be a viable approach for the treatment of depression in Parkinson's disease. Further research is needed to replicate and extend these findings.

Mesencephalic midline change on transcranial sonography in early Parkinson's disease patients with depression

Recently, several studies using transcranial sonography (TCS) have resulted in the alteration of the mesencephalic midline in patients with depression. We aimed to investigate and compare sonographic abnormalities in the brainstem raphe (BR) in patients with Parkinson's disease (PD) and controls, according to presence of depression. Study participants totaled 61 patients with PD (29 PD without depression, 32 PD with depression) and 41 controls. Results indicated that decreased BR echogenicity was much higher in PD patients with depression (PD+D) than in those without depression (PD-D). Of the 61 PD patients, 32 (52.4%) had depression as diagnosed by psychiatric assessment, and 13 (17.6%) were excluded, due to insufficient temporal windows. Based on these results, the use of TCS with respect to the mesencephalic midline may be useful in detecting depression, a risk factor for the development of PD.

Serotonin-dependent depression in Parkinson's disease: a role for the subthalamic nucleus?

Depression is the most common neuropsychiatric co-morbidity in Parkinson's disease (PD). The underlying mechanism of depression in PD is complex and likely involves biological, psychosocial and therapeutic factors. The biological mechanism may involve changes in monoamine systems, in particular the serotonergic (5-hydroxytryptamine, 5-HT) system. It is well established that the 5-HT system is markedly affected in the Parkinsonian brain, with evidence including pathological loss of markers of 5-HT axons as well as cell bodies in the dorsal and median raphe nuclei of the midbrain. However, it remains unresolved whether alterations to the 5-HT system alone are sufficient to confer vulnerability to depression. Here we propose low 5-HT combined with altered network activity within the basal ganglia as critically involved in depression in PD. The latter hypothesis is derived from a number of recent findings that highlight the close interaction between the basal ganglia and the 5-HT system, not only in motor but also limbic functions. These findings include evidence that clinical depression is a side effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN), a treatment option in advanced PD. Further, it has recently been demonstrated that STN DBS in animal models inhibits 5-HT neurotransmission, and that this change may underpin depressive-like side effects. This review provides an overview of 5-HT alterations in PD and a discussion of how these changes might combine with altered basal ganglia network activity to increase depression vulnerability.

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.

Dreaming and cognition in patients with frontotemporal dysfunction

Individuals with Parkinson's disease (PD) and temporal lobe epilepsy (TLE) have hallucinations and mild cognitive dysfunction. The objective of this work was to study dreams in PD and TLE patients using a common functional model of dream production involving the limbic and paralimbic structures. Dreams were characterised in early-stage PD (19 males) and TLE patients (52) with dream diaries classified by the Hall van de Castle system and were compared with matched controls. In PD, there were significant differences between patients' dreams and those of controls: animals, physical aggression, and a befriender were more common in patients, and aggressor and bodily misfortunes were less common. The dreams of patients with frontal dysfunction showed more aggressive features. TLE patients had lower recall than PD patients and a higher proportion of dreams involving family and familiar settings, lower proportions involving success, and a higher incidence of frontal dysfunction. The dreams of PD and TLE patients share important features.

Diagnostic criteria for depression in Parkinson's disease: a study of symptom patterns using latent class analysis

Although major depression is one of the most frequent psychiatric disorders among patients with Parkinson's disease, diagnostic criteria have yet to be validated. The main aim of our study was to validate depressive symptoms using latent class analysis for use as diagnostic criteria for major depression in Parkinson's disease. We examined a consecutive series of 259 patients with Parkinson's disease admitted to 2 movement disorders clinics for regular follow-ups. All patients were assessed with a comprehensive psychiatric interview that included structured assessments for depression, anxiety, and apathy. The main finding was that all 9 Diagnostic and Statistical Manual (4th edition) diagnostic criteria for major depression (ie, depressed mood, diminished interest or pleasure, weight or appetite changes, sleep changes, psychomotor changes, loss of energy, feelings of worthlessness or inappropriate guilt, poor concentration, and suicidal ideation) identified a patient class (severe depression group) with high statistical significance. Latent class analysis also demonstrated a patient class with minimal depressive symptoms (no-depression group), and a third patient class with intermediate depressive symptoms (moderate depression). Anxiety and apathy were both significant comorbid conditions of moderate and severe depression. Taken together, our findings support the use of the full Diagnostic and Statistical Manual (4th edition) criteria for major depression for use in clinical practice and research in Parkinson's disease and suggest that anxiety may be included as an additional diagnostic criterion.

The relationship between depression and regional cerebral blood flow in Parkinson's disease and the effect of selegiline treatment

OBJECTIVES

We examined the relationship between severity of depression in Parkinson's disease (PD) and regional cerebral blood flow (rCBF) using single photon emission computed tomography (SPECT) and the reaction to levodopa-selegiline combination therapy.

MATERIALS AND METHODS

We evaluated 52 patients with PD and nine age-matched controls with SPECT and the Unified Parkinson's Disease Rating Scale (UPDRS) part III, Mini-Mental State Examination (MMSE), and Beck Depression Inventory (BDI) to evaluate depression severity and its connection with rCBF. Furthermore, we examined rCBF in patients with PD treated with levodopa with or without selegiline.

RESULTS

A significant fall in rCBF was observed in the bilateral posterior cingulate, hippocampus, and cuneus and the superior parietal and primary visual areas in PD patients with minor depression and in all regions in those with major depression. Elevations in UPDRS part III and BDI scores and falls in MMSE scores were of significantly lower magnitude in the levodopa-selegiline group than in the levodopa group. Whole brain rCBF fell significantly less in the levodopa-selegiline group than in the levodopa group.

CONCLUSIONS

These results indicate that selegiline controlled not only worsening of motor function and cognitive function in PD but also aggravation of minor depression, and restrained a fall in whole brain rCBF.

Changes in cognitive-emotional and physiological symptoms of depression following STN-DBS for the treatment of Parkinson's disease

BACKGROUND AND PURPOSE

Subthalamic nucleus deep brain stimulation (STN-DBS) has been shown to have beneficial effects on the motor features of Parkinson's disease (PD), but its impact on non-motor symptoms, most notably mood, has not been fully explored.

METHODS

In the first study to independently compare the emotional-cognitive and somatic/physiological symptoms of depression, we examined mood differences in 17 bilateral STN-DBS and 22 matched non-surgical PD patients at baseline and 6 months.

RESULTS

The STN-DBS group reported higher levels of depression at baseline with significant endorsement of physical symptomatology. Postoperatively, no significant between-group differences in physical symptoms of depression were found. In contrast, a significant group by time interaction for cognitive-emotional symptoms of depression was found, with the STN-DBS group reporting an increase in psychological symptoms of distress. The STN-DBS group also reported an increase in anxiety following surgery. The suicide rate of 5% found in our study is consistent with other postoperative studies in PD. The impact of changes in levodopa and psychotropic medication are also explored.

CONCLUSIONS

Preliminary results suggest that the motor improvement often observed in patients with PD following bilateral STN-DBS may be partially offset by an increase in affective-cognitive symptoms of depression.

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.

The role of dopamine agonists in the treatment of depression in patients with Parkinson's disease: a systematic review

Depressive disorders as well as depressive symptoms are common in Parkinson's disease (PD) and an important factor affecting quality of life. Treatment of depressive symptoms not only improves mood but is also associated with improvement of motor symptoms, disability and cognitive symptoms. Currently, dopamine agonists are being suggested as an alternative to antidepressants for the treatment of depression in PD. The aim of this article is to systematically review the efficacy of dopamine agonists in the treatment of depression in PD. Since 1983, 19 studies have reported on the effects of dopamine agonists on depressive disorder, depressive symptoms or mood in PD. To date, no double-blind, placebo-controlled, randomized controlled trial of the treatment of major depressive disorder in PD with a dopamine agonist has been conducted. Studies of the effects of treatment with dopamine agonists on depressive symptoms in PD, or on mood in non-depressed PD patients, have yielded inconclusive results. Most studies are not designed to test effects on mood and are limited by methodological flaws. It can be concluded that, although the preliminary evidence of the effects on mood and depression in PD is interesting and in need of further study, there is as yet insufficient evidence to recommend dopamine agonists in the treatment of either depressive disorder or depressive symptoms in patients with PD. Treatment of depressive disorder and clinically relevant depressive symptoms should be based on pharmacological or non-pharmacological interventions with known efficacy in this population, such as citalopram, nortriptyline, desipramine or cognitive behavioural therapy. This strategy has the additional advantage of enabling the clinician to treat depressive symptoms independently of motor symptoms, thus avoiding potential complications of dopaminergic therapy.

The impact of sleep and mood disorders on quality of life in Parkinson's disease patients

Sleep disturbances are common and often severe in patients with Parkinson's disease (PD) and their symptoms can be present at any time of day. The purpose of our study was to examine how excessive daytime sleepiness or poor nocturnal sleep quality and mood disorders influence the quality of life (QoL) in PD patients. Ninety-three PD patients from eastern Slovakia were recruited (49.5% males, mean age 68.0 ± 9.5 years, mean disease duration 6.1 ± 5.9 years). Sleep disturbances were measured using the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI); QoL with the Parkinson's Disease Quality of Life Questionnaire (PDQ-39); depression and anxiety with the Hospital Anxiety and Depression Scale (HADS) and disease severity with the Unified Parkinson's Disease Rating Scale (UPDRS). χ (2) test, bivariate correlations and multiple linear regressions were performed. PSQI and ESS had significant correlations with worse QoL (p < 0.01, p < 0.05, respectively). HADS-D (p < 0.01), HADS-A (p < 0.01), UPDRS (p < 0.01) and disease duration (p < 0.05) were also significantly related to worse QoL. In the linear regression analysis, however, only PSQI (p < 0.01), anxiety (p < 0.001) and UPDRS (p < 0.001) remained significant. The model with PSQI explained 74% of the variance, and the model with ESS explained 63% of the variance in PDQ-39 when analyses were performed separately. In an overall model, however, only PSQI remained significant, accounting for 82% of the variance in PDQ-39. Nighttime poor sleep and anxiety are important contributors leading to a worse QoL. As these are treatable conditions, they should be recognized by clinicians and managed properly.

Parkinson's disease: the quintessential neuropsychiatric disorder

Although diagnosed by characteristic motor features, Parkinson's disease may be preceded, and is frequently accompanied by, a wide range of cognitive and neuropsychiatric features. In addition to the most commonly studied disorders of dementia, depression, and psychosis, other relatively common and clinically significant psychiatric complications include impulse control disorders, anxiety symptoms, disorders of sleep and wakefulness, and apathy. These problems may be underrecognized and are frequently undertreated. The emergent focus on nonmotor aspects of Parkinson's disease over the past quarter of a century is highlighted by a nonlinear increase in the number of articles published devoted to this topic. Although the development of newer antidepressants, atypical antipsychotics, and cholinesterase inhibitors in recent years has had a positive benefit on the management of these troublesome and distressing symptoms, responses are frequently suboptimal, and this remains an area of major unmet therapeutic need.

Apathy, but not depression, reflects inefficient cognitive strategies in Parkinson's disease

BACKGROUND

The relationship between apathy, depression and cognitive impairment in Parkinson's disease (PD) is still controversial. The objective of this study is to investigate whether apathy and depression are associated with inefficient cognitive strategies in PD.

METHODS

In this prospective clinical cohort study conducted in a university-based clinical and research movement disorders center we studied 48 PD patients. Based on clinical evaluation, they were classified in two groups: PD with apathy (PD-A group, n = 23) and PD without apathy (PD-NA group, n = 25). Patients received clinical and neuropsychological evaluations. The clinical evaluation included: Apathy Evaluation Scale-patient version, Hamilton Depression Rating Scale-17 items, the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr staging system; the neuropsychological evaluation explored speed information processing, attention, working memory, executive function, learning abilities and memory, which included several measures of recall (immediate free, short delay free, long delay free and cued, and total recall).

FINDINGS

PD-A and PD-NA groups did not differ in age, disease duration, treatment, and motor condition, but differed in recall (p<0.001) and executive tasks (p<0.001). Immediate free recall had the highest predictive value for apathy (F = 10.94; p = 0.002). Depression and apathy had a weak correlation (Pearson index= 0.3; p<0.07), with three items of the depression scale correlating with apathy (Pearson index between .3 and.4; p<0.04). The depressed and non-depressed PD patients within the non-apathetic group did not differ.

CONCLUSION

Apathy, but not depression, is associated with deficit in implementing efficient cognitive strategies. As the implementation of efficient strategies relies on the fronto-striatal circuit, we conclude that apathy, unlike depression, is an early expression of executive impairment in PD.

Anxiety rating scales in Parkinson's disease: a validation study of the Hamilton anxiety rating scale, the Beck anxiety inventory, and the hospital anxiety and depression scale

BACKGROUND

Anxiety is a prevalent and disabling condition in Parkinson's disease (PD). The lack of anxiety rating scales validated for this population hampers research into anxiety in PD. The aim of this study is to assess the clinimetric properties of the Hamilton anxiety rating scale (HARS), the Beck anxiety inventory (BAI), and the hospital anxiety and depression scale (HADS) in PD patients.

DESIGN

Three hundred forty-two PD patients underwent a standardized assessment including a structured interview for diagnostic and statistical manual diagnoses of anxiety disorders and completion of the HARS, BAI, and HADS. Inter-rater reliability of the HARS was assessed in 60 patients; test-retest reliability of the BAI and HADS in 213 and 217 patients, respectively.

RESULTS

Thirty-four percent of patients suffered from an anxiety disorder, whereas an additional 11.4% had clinically significant anxiety symptoms in the absence of a diagnosis of anxiety disorder. Acceptability, score distribution, and known groups validity over different levels of anxiety were adequate. Inter-rater reliability for the HARS and test-retest reliability for the BAI and HADS were good. The HARS, but not the BAI and HADS, had a satisfactory inter-item correlation, convergent validity and factorial structure. For all scales, the positive predictive value was poor, and the negative predictive value was moderate.

CONCLUSIONS

Given the adequate known groups validity of all three rating scales, each of these scales is likely to be useful in clinical practice or research for evaluation of symptom severity. Limitations in the construct validity of the anxiety scales in this study raise questions regarding suitability for their use in PD.

The impact of left prefrontal repetitive transcranial magnetic stimulation on depression in Parkinson's disease: a randomized, double-blind, placebo-controlled study

Based on several open-label and case studies, repetitive transcranial magnetic stimulation (rTMS) seems to have an antidepressive effect on patients with Parkinson's disease (PD). However, this hypothesis requires further confirmation. We conducted a randomized, double-blind placebo-controlled study to evaluate the effect of rTMS over the left dorsolateral prefrontal cortex (DLPFC) on depression and various motor and nonmotor features of PD. Twenty-two PD patients with mild or moderate depressive episodes were assigned into two groups, one receiving real-rTMS (90% of resting motor threshold, 5 Hz, 600 pulses-a-day for 10 days) over the left DLPFC, and another group receiving sham-rTMS. An investigator blinded to the treatment performed three video-taped examinations on each patient: before stimulation (baseline), 1 day (short term), and 30 days after treatment session ended (long-term effect). Mini-Mental State Examination, Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn-Yahr, Epworth Sleepiness, Visual Analog and Montgomery-Asberg Depression Rating Scales (MADRS), Beck Depression Inventory (BDI), and Trail making and Stroop tests were applied. In the actively treated group, not only depression rating scales showed significant improvement 30 days after treatment ended (BDI by 44.4% and MADRS by 26.1%), but also the accuracy of Stroop test (by 16%). We could also demonstrate an insignificant improvement in UPDRS-III by 7.5 points (31.9%, P = 0.06). In the sham-treated group none of the examined tests and scales improved significantly after sham stimulation. Our study demonstrated the beneficial effect of the left DLPFC rTMS on depression in PD lasting at least 30 days after treatment. However, this result should be confirmed in patients with severe depression by further clinical trials.

Symptomatology and markers of anxiety disorders in Parkinson's disease: a cross-sectional study

Anxiety is understudied in Parkinson's disease (PD), which is not justified by the prevalence and impact of anxiety disorders on quality of life in PD patients. In this cross-sectional study, 342 patients suffering from idiopathic PD underwent a research-based assessment including DSM IV criteria for anxiety disorders, the Hamilton anxiety rating scale (HARS) and the beck anxiety inventory (BAI). Thirty-four percent (34%) of subjects met the DSM IV criteria for at least one anxiety disorder; 11.8% met criteria for multiple anxiety disorders; and 11.4% had clinically relevant anxiety symptoms without meeting the criteria for any specific anxiety disorder. Score profiles on the HARS and BAI differed significantly between the disorders, but these differences were associated with different scores on a limited number of items, and the respective symptom profiles were not readily interpretable. Female sex, the presence of motor fluctuations, as well as a previous history of an anxiety disorder were markers for anxiety disorders. The use of a mono-amino oxidase (MAO)-B inhibitor was associated with a reduced prevalence of anxiety disorders. Research into anxiety in PD is hampered by the questionable validity of DSM IV defined anxiety disorders in this population. A first focus for research should therefore be the identification of clinically useful anxiety presentations and their validation in PD.

Treatment of advanced Parkinson's disease

Patients at late stage Parkinson's disease (PD) develop several motor and nonmotor complications, which dramatically impair their quality of life. These complications include motor fluctuations, dyskinesia, unpredictable or absent response to medications, falls, dysautonomia, dementia, hallucinations, sleep disorders, depression, and psychosis. The therapeutic management should be driven by the attempt to create a balance between benefit and side effects of the pharmacological treatments available. Supportive care, including physical and rehabilitative interventions, speech therapy, occupational therapy, and nursing care, has a key role in the late stage of disease. In this review we discuss the several complications experienced by advance PD patients and their management. The importance of an integrative approach, including both pharmacological and supportive interventions, is emphasized.

Identification of blood microRNAs associated to Parkinsonĭs disease

The present study demonstrates that blood samples can be used as a source of miRNA identification associated to Parkinson's disease (PD). A set of six differentially expressed microRNAs were identified. They form two groups according to their expression profile in control, non-treated, early-onset and treated Parkinson's disease subjects. While miR-1, miR-22* and miR-29 expression levels allowed to distinguish non-treated PD from healthy subjects, miR-16-2*, miR-26a2* and miR30a differentiated treated from untreated patients. This study is innovative in contributing to the development of effective PD biomarkers.

Modulation of subthalamic alpha activity to emotional stimuli correlates with depressive symptoms in Parkinson's disease

BACKGROUND

Deep brain stimulation of the subthalamic nucleus is an effective treatment for patients with advanced Parkinson's disease. However, affective side effects following subthalamic deep brain stimulation have been reported. Here, we aim to elucidate the influence of affective state on emotional processing as indexed by local field potential activity and to identify neurophysiological markers in patients at risk of developing depressive symptoms during subthalamic deep brain stimulation.

METHODS

Subthalamic local field potentials were directly recorded via electrodes implanted for deep brain stimulation in 12 Parkinson's disease patients while viewing emotionally salient and neutral pictures. Parkinson's disease patients were assessed for depressive symptoms using the Beck depression inventory at the time of operation and 3 months after continuous subthalamic nucleus deep brain stimulation.

RESULTS

We found a significant event-related desynchronization in the local alpha frequency band (8-12 Hz) for emotionally arousing but not neutral pictures. The the event-related desynchronization (ERD) in the alpha frequency band was reduced for pleasant stimuli in patients with mild to moderate depressive symptoms compared with patients without depression. The alpha-ERD to unpleasant stimuli showed the opposite pattern. Consistently, the index of event-related alpha desynchronization (alpha ERD for pleasant stimuli minus alpha ERD for unpleasant stimuli) correlated with the Beck depression inventory at the time of the recordings and at 3 months after continuous deep brain stimulation. The alpha ERD to unpleasant pictures correlated significantly with the Beck depression inventory score at 3 months after chronic deep brain stimulation.

DISCUSSION

In conclusion, we found mood-congruent stimulus processing in the subthalamic nucleus of Parkinson's disease patients. Electrophysiological markers such as event-related desynchronization of subthalamic alpha activity reflect state-dependent emotional processing and may potentially be used to predict depressive mood disturbances in Parkinson's disease patients with chronic subthalamic deep brain stimulation at an early stage.

Anhedonia in Japanese patients with Parkinson's disease

AIM

Anhedonia has been proposed as a specific mood disorder related to the dopaminergic nerve dysfunction seen in Parkinson's disease (PD). This study examined hedonic tone in patients with PD using the Snaith-Hamilton Pleasure Scale (SHAPS) and investigated the associations with depressive mood by the Self-Rating Questionnaire for Depression (SRQ-D).

METHODS

This study examined 100 patients with PD and 111 age-matched controls (C2) recruited from 300 healthy subjects (C1) to compare the frequency of anhedonia and to clarify whether anhedonia in PD is associated with depression and anti-Parkinson medication.

RESULTS

Forty-six percent of PD patients revealed possible/probable depression and 10 patients (10%) with PD showed anhedonia as compared to 3.3% in C1 and 2.7% in C2. The reduction in hedonic tone was related to depression in PD. Among 10 PD patients with anhedonia, seven were in anhedonia with depression and three were in anhedonia without depression. There was no sex difference in anhedonia and depression. No patients treated with pramipexole showed anhedonia but also the highest proportion of normal hedonic tone was found in patients treated with pramipexole among PD patients. In analysis of each SHAPS item, no significant difference was seen on social interaction scores in contrast to the significant reduction of interest/pastimes and sensory experience and food/drink scores between PD patients and C1/C2.

CONCLUSION

Anhedonia may overlap depressive syndrome but some PD patients without depression presented anhedonia. Pramipexole could maintain hedonic tone. The PD patients could enjoy attracting attention and wish to do things helpful for others.

Exercise and Parkinson's: benefits for cognition and quality of life

OBJECTIVES

The benefits of physical exercise for psychological aspects of quality of life (QoL) are well established in normally ageing adults, yet potential benefits for people with Parkinson's disease (PD) have received limited attention. This study evaluated the benefits of exercise for cognitive functioning, mood and disease-specific QoL for people with PD.

METHODS

Twenty-eight individuals with PD were allocated to an exercise intervention program (EIP, n = 15) or control group (n = 13). The EIP group undertook a programme of progressive anabolic and aerobic exercise twice weekly for 12 weeks. The control group maintained their usual lifestyle.

RESULTS

Exercise was shown to have selective benefits for cognitive functioning by improving frontal lobe based executive function. No significant effects were demonstrated for mood or disease-specific QoL.

CONCLUSIONS

These results are consistent with previous research demonstrating selective benefits of exercise for executive function among normal ageing adults and PD.

Scales to assess sleep impairment in Parkinson's disease: critique and recommendations

There is a broad spectrum of sleep disturbances observed in Parkinson's disease (PD). A variety of scales have been applied to the evaluation of PD sleep and wakefulness, but only a small number have been assessed specifically for clinimetric properties in the PD population. The movement disorder society has commissioned this task force to examine these scales and to assess their use in PD. A systematic literature review was conducted to explore the use of sleep scales in PD and to determine which scales qualified for a detailed critique. The task force members, all of whom have extensive experience in assessing sleep in PD reviewed each of the scales using a structured proforma. Scales were categorized into recommended, suggested and listed according to predefined criteria. A total of 48 potential scales were identified from the search and reviewed. Twenty-nine were excluded because they did not meet review criteria or were variations of scales already included, leaving 19 scales that were critiqued and rated by the task force based on the rating criteria. Only six were found to meet criteria for recommendation or suggestion by the task force: the PD sleep scale (PDSS) and the Pittsburgh sleep quality index (PSQI) are recommended for rating overall sleep problems to screen and to measure severity, the SCOPA-sleep (SCOPA) is recommended for rating overall sleep problems both to screen and to measure severity, and for rating daytime sleepiness; the Epworth sleepiness scale (ESS) is recommended for rating daytime sleepiness to screen and to measure severity; the inappropriate sleep composite score (ISCS) is suggested for rating severe daytime sleepiness or sleep attacks to screen and to measure severity; and the Stanford sleepiness scale (SSS) is suggested for rating sleepiness and to measure severity at a specific moment. The task force does not recommend the development of new scales, but emphasizes the need for educational efforts to train physicians in sleep interview techniques and polysomnography.

Diagnostic accuracy and agreement across three depression assessment measures for Parkinson's disease

PURPOSE

To assess diagnostic accuracy of two self-administered depression measures compared to an interviewer-administered measure in subjects with Parkinson's disease (PD), and to analyze clinical and sociodemographic factors associated with disagreement among the three depression assessment tools.

METHODS

We assessed 214 PD subjects using the Patient Health Questionnaire-9 (PHQ-9), the Geriatric Depression Scale-15 (GDS-15), and the Structured Clinical Interview for the DSM-IV depression module (SCID). Diagnostic accuracy of the PHQ-9 and GDS-15 compared to the SCID was evaluated. Multivariate logistic regression was conducted to analyze factors associated with measure disagreement. We compared item agreement between the PHQ-9 and SCID to test the hypothesis that there would be less agreement between items assessing depression symptoms overlapping with common PD symptoms, compared to items having minimal overlap with PD manifestations.

RESULTS

Compared to SCID diagnosis of major depression, PHQ-9 sensitivity is 50% and specificity is 93%; GDS-15 sensitivity is 43% and specificity is 96%. The GDS-15 has 85% sensitivity and 79% specificity and the PHQ-9 has 54% sensitivity and 85% specificity compared to SCID diagnosis of minor or major depression. The PHQ-9 and SCID show more agreement on items unrelated to PD manifestations. Pain was the only factor associated with disagreement between the SCID and PHQ-9.

CONCLUSION

Compared to the PHQ-9, the GDS-15 had higher sensitivity and similar positive predictive value, suggesting it is a superior screening tool in clinical applications for PD. On future depression screening or diagnostic instruments, consideration should be given to excluding depression items overlapping with PD manifestations.

Mild cognitive impairment in Parkinson disease: a multicenter pooled analysis

BACKGROUND

In studies of mild cognitive impairment (MCI) in Parkinson disease (PD), patients without dementia have reported variable prevalences and profiles of MCI, likely to be due to methodologic differences between the studies.

OBJECTIVE

The objective of this study was to determine frequency and the profile of MCI in a large, multicenter cohort of well-defined patients with PD using a standardized analytic method and a common definition of MCI.

METHODS

A total of 1,346 patients with PD from 8 different cohorts were included. Standardized analysis of verbal memory, visuospatial, and attentional/executive abilities was performed. Subjects were classified as having MCI if their age- and education-corrected z score on one or more cognitive domains was at least 1.5 standard deviations below the mean of either control subjects or normative data.

RESULTS

A total of 25.8% of subjects (95% confidence interval [CI] 23.5-28.2) were classified as having MCI. Memory impairment was most common (13.3%; 11.6-15.3), followed by visuospatial (11.0%; 9.4-13.0) and attention/executive ability impairment (10.1%; 8.6-11.9). Regarding cognitive profiles, 11.3% (9.7-13.1) were classified as nonamnestic single-domain MCI, 8.9% (7.0-9.9) as amnestic single-domain, 4.8% (3.8-6.1) as amnestic multiple-domain, and 1.3% (0.9-2.1) as nonamnestic multiple-domain MCI. Having MCI was associated with older age at assessment and at disease onset, male gender, depression, more severe motor symptoms, and advanced disease stage.

CONCLUSIONS

MCI is common in patients with PD without dementia, affecting a range of cognitive domains, including memory, visual-spatial, and attention/executive abilities. Future studies of patients with PD with MCI need to determine risk factors for ongoing cognitive decline and assess interventions at a predementia stage.

Economic burden of Parkinson's disease in Singapore

BACKGROUND

This study was carried out to evaluate the economic burden of Parkinson's disease (PD) and factors independently associated with individual components of total cost in Singapore.

METHODS

A consecutive sample of 195 patients with PD (mean age: 68.2, men: 51.8%) attending a tertiary neuroscience clinic were identified and interviewed using standardized questionnaires including a financial burden questionnaire, two Health Related Quality of Life (HRQoL) questionnaires and the Beck Depression Inventory questionnaire.

RESULTS

Annual total cost of PD from a societal perspective was SGD11345 (USD10129) per patient, with direct cost accounted for 38.5% and indirect cost 61.5%. The main cost components for direct medical cost, direct non-medical cost, and indirect cost was pharmacotherapy (50.4%), home care (76.1%), and productivity loss (97.9%), respectively. In multiple linear regression analysis, higher education, younger age and longer duration of PD were associated with higher total cost.

CONCLUSIONS

Parkinson's disease exerts a considerable burden on patients, health care system and society in Singapore. As productivity loss accounts for a large share of the economic burden imposed by PD, treatments and health care programmes with potential for returning patients to higher productivity are urgently needed.

Serotonergic neurotransmission in early Parkinson's disease: a pilot study to assess implications for depression in this disorder

OBJECTIVES

Depression, a disease usually accompanied by a serotonergic deficit, has been observed in about 40% of patients suffering from Parkinson's disease (PD). Thus, a serotonergic dysfunction in PD can be assumed. We aimed to investigate the interaction between serotonergic (5-HT) and dopaminergic activity in early PD. We hypothesized a serotonergic as well as a dopaminergic deficit in PD patients. We also assumed a correlation between these neurotransmitters indicating a relationship between dopaminergic and serotonergic function in PD.

METHODS

Nine unmedicated PD patients before and 12 weeks after L-dopa treatment and nine healthy subjects were examined using the loudness dependence of auditory evoked potentials (LDAEP), a promising indicator of central serotonergic function. Dopaminergic transporters (DAT) were collected using (123)I-FP-CIT and single photon emission computer tomography (SPECT). LDAEP values were correlated with (123)I-FP-CIT SPECT data.

RESULTS

A significant difference between LDAEP of controls and patients (P= 0.05) suggested lower serotonergic activity in PD. Twelve weeks after initiation of L-dopa treatment this difference was lost between patients and controls (P= 0.20). There was a trend towards a correlation between LDAEP and DAT (r= 0.65; P = 0.057) of the unmedicated patients, suggesting a low serotonergic activity may be related to a dopamine deficit in PD.

CONCLUSIONS

Our results support the hypothesis that serotonergic neurotransmission is decreased in untreated PD and suggest that a low serotonergic activity may be related to the dopamine pathology in PD. This could be related to the high prevalence of depression in PD.

Fatigue rating scales critique and recommendations by the Movement Disorders Society task force on rating scales for Parkinson's disease

Fatigue has been shown to be a consistent and common problem in Parkinson's disease (PD) in multiple countries and cultures. It is one of the most disabling of all symptoms, including motor dysfunction, and appears early, often predating the onset of motor symptoms. Several studies of the epidemiology of fatigue have been published, often using different scales, but few on treatment. The Movement Disorder Society (MDS) commissioned a task force to assess available clinical rating scales, critique their psychometric properties, summarize their clinical properties, and evaluate the evidence in support of their use in clinical studies in PD. Six clinical researchers reviewed all studies published in peer reviewed journals of fatigue in PD, evaluated the scales' previous use, performance parameters, and quality of validation data, if available. Scales were rated according to criteria provided by the MDS. A scale was "recommended" if it has been used in clinical studies beyond the group that developed it, has been used in PD and psychometric studies have established that it is a valid, reliable and sensitive to change in people with PD. Requiring a scale to have demonstrated sensitivity to change in PD specifically rather than in other areas in order to attain a rating of "recommended" differs from the use of this term in previous MDS task force scale reviews. "Suggested" scales failed to meet all the criteria of a "recommended" scale, usually the criterion of sensitivity to change in a study of PD. Scales were "listed" if they had been used in PD studies but had little or no psychometric data to assess. Some scales could be used both to screen for fatigue as well as to assess fatigue severity, but some were only used to assess severity. The Fatigue Severity Scale was "recommended" for both screening and severity rating. The Fatigue Assessment Inventory, an expanded version of the Fatigue severity Scale, is "suggested" for both screening and severity. The Functional Assessment of Chronic Illness Therapy-Fatigue was "recommended" for screening and "suggested" for severity. The Multidimensional Fatigue Inventory was "suggested" for screening and "recommended" for severity. The Parkinson Fatigue Scale was "recommended" for screening and "suggested" for severity rating. The Fatigue Severity Inventory was "listed" for both screening and severity. The Fatigue Impact Scale for Daily Use, an adaptation of the Fatigue Impact Scale was "listed" for screening and "suggested" for severity. Visual Analogue and Global Impression Scales are both "listed" for screening and severity. The committee concluded that current scales are adequate for fatigue studies in PD but that studies on sensitivity and specificity of the scales are still needed.