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

Depression is a common comorbid condition in Parkinson's disease (PD) and a major contributor to poor quality of life and disability. However, depression can be difficult to assess in patients with PD due to overlapping symptoms and difficulties in the assessment of depression in cognitively impaired patients. As several rating scales have been used to assess depression in PD (dPD), the Movement Disorder Society commissioned a task force to assess their clinimetric properties and make clinical recommendations regarding their use. A systematic literature review was conducted to explore the use of depression scales in PD and determine which scales should be selected for this review. The scales reviewed were the Beck Depression Inventory (BDI), Hamilton Depression Scale (Ham-D), Hospital Anxiety and Depression Scale (HADS), Zung Self-Rating Depression Scale (SDS), Geriatric Depression Scale (GDS), Montgomery-Asberg Depression Rating Scale (MADRS), Unified Parkinson's Disease Rating Scale (UPDRS) Part I, Cornell Scale for the Assessment of Depression in Dementia (CSDD), and the Center for Epidemiologic Studies Depression Scale (CES-D). Seven clinical researchers with clinical and research experience in the assessment of dPD were assigned to review the scales using a structured format. The most appropriate scale is dependent on the clinical or research goal. However, observer-rated scales are preferred if the study or clinical situation permits. For screening purposes, the HAM-D, BDI, HADS, MADRS, and GDS are valid in dPD. The CES-D and CSDD are alternative instruments that need validation in dPD. For measurement of severity of depressive symptoms, the Ham-D, MADRS, BDI, and SDS scales are recommended. Further studies are needed to validate the CSDD, which could be particularly useful for the assessment of severity of dPD in patients with comorbid dementia. To account for overlapping motor and nonmotor symptoms of depression, adjusted instrument cutoff scores may be needed for dPD, and scales to assess severity of motor symptoms (e.g., UPDRS) should also be included to help adjust for confounding factors. The HADS and the GDS include limited motor symptom assessment and may, therefore, be most useful in rating depression severity across a range of PD severity; however, these scales appear insensitive in severe depression. The complex and time-consuming task of developing a new scale to measure depression specifically for patients with PD is currently not warranted.     

Translation and validation of the standard Chinese version of PDQ-39: a quality-of-life measure for patients with Parkinson's disease.

PDQ-39 has been widely used in the research and clinical management of Parkinson's disease. It has been translated into and validated in various non-English languages. We report here on the validity and reliability results for the translated standard Chinese PDQ-39 questionnaire. Fifty-four patients were recruited from a movement disorder clinic and two regional patient groups, and data were collected by direct interview. Nineteen patients had the tests repeated 4 weeks later to assess the test-retest and interrater reliability. The standard Chinese version of PDQ-39 demonstrated acceptable internal consistency (Cronbach's alpha = 0.54-0.90) and was comparable to versions in other languages. Further analysis showed good construct validity and test-retest reliability. Implications and limitations of the study are discussed.     

Health-related quality of life evaluation by proxy in Parkinson's disease: approach using PDQ-8 and EuroQoL-5D.

Patient- and caregiver-based scores were compared and agreement levels ascertained to determine the reliability of proxy evaluation of Parkinson's Disease (PD) patients' health-related quality of life (HRQoL) using the EuroQoL and PD questionnaire (PDQ)-8. Of 72 patient-caregiver pairs, 64 (88.88%) returned the questionnaires. The degree of agreement varied for individual dimensions. Proxy evaluation of PD patients' HRQoL showed limitations mainly with assessments using the EuroQoL and especially in patients with severe disease and depression.     

Validity and reliability of the PDQ-39 and the PDQ-8 in English-speaking Parkinson's disease patients in Singapore

The purpose of the study was to assess the validity and reliability of the Parkinson's disease questionnaire (PDQ-39, UK English version) as well as its briefer version (the PDQ-8) among Asian patients with Parkinson's disease (PD) in Singapore. Eighty-eight patients recruited from movement disorder clinics or patient support groups completed the PDQ-39 and EQ-5D, a generic health related quality of life questionnaire previously validated for use in Singapore. PDQ-39 items showed good convergent and discriminant validity. Construct validation against the EQ-5D showed strong correlation between these scales as hypothesised (Spearman's ρ: 0.53–0.71, P<0.001 for all). Factor analysis yielded a component on which all eight PDQ-39 dimensions were substantially loaded (loading range: 0.50–0.79). The PDQ-39 also demonstrated acceptable internal consistency (Cronbach's : 0.59–0.94) and test–retest reliability (intra-class correlation coefficient:0.67–0.87, n=68). Six of eight PDQ-8 items showed the strongest correlation with their PDQ-39 dimensions as hypothesised. PDQ-39 and PDQ-8 summary indexes were highly correlated (Pearson's r=0.96, ICC=0.95), and both were strongly correlated with the EQ-5D utility index and EQ-5D visual analogue scale (P<0.001). We conclude that the PDQ-39 and PDQ-8 are valid and reliable disease-specific HRQoL instruments for PD in Singapore.     

Respondent burden and patient-perceived validity of the PDQ-39

OBJECTIVES: To evaluate the respondent burden and patient-perceived content validity of the Parkinson's disease (PD)-specific health status questionnaire PDQ-39, and the linguistic validity of its revised Swedish version. MATERIALS AND METHODS: Eighteen PD patients completed the revised Swedish version of the PDQ-39. Respondent burden was assessed by recording the time taken to complete the questionnaire. Content and linguistic validity was evaluated qualitatively. RESULTS: Patients with mild, moderate and advanced PD needed a mean time of 9.5, 11.3 and 20.1 min, respectively, to complete the PDQ-39. One-third of the patients identified irrelevant items and 50% identified important health-related areas that were missing. Revisions had eliminated previous linguistic problems with the Swedish PDQ-39. CONCLUSIONS: Undue respondent burden challenged the appropriateness of the PDQ-39 among patients with more advanced disease. Overall content validity was acceptable but compromised by lack of important content areas. Observations supported the linguistic validity of the revised Swedish PDQ-39.     

Predicting the cost of Parkinson's disease.

The degenerative nature of Parkinson's disease (PD) suggests that it will lead to high levels of resource use. This study measures service use and costs for a representative community sample of PD patients and identifies cost predictors. Patients were identified from general practices and were interviewed twice, separated by a 12-month interval. Demographic and clinical data on patients were collected and 6-month costs were calculated. Regression analysis was used to identify significant baseline predictors of follow-up costs. The annual service costs (baseline and follow-up combined) were 13,804 pounds per person. Formal service costs accounted for 20% of this figure with informal care from families/friends accounting for 80%. The regression model explained 42% of total follow-up costs and significant predictors included gender (with men having higher costs), disability, and depression.     

Rasch analysis of the hospital anxiety and depression scale in Parkinson's disease

The hospital anxiety and depression scale (HADS) is commonly used to assess mood in Parkinson's disease (PD) patients. Very few studies analyze the scale from the standpoint of item response theory. This article sought to analyze how the HADS fits the Rasch model in PD. The HADS was administered to 387 PD patients. Three sets of Rasch analyses were performed for the HADS total score, and anxiety and depression subscales (HADS‐T, ‐A, and ‐D, respectively). Although the HADS‐T and HADS‐A displayed a good fit, with little threshold disordering and no differential item functioning, the HADS‐D failed to fit the model. The person separation index, a reliability measure, was 0.87 (HADS‐T) and 0.80 (HADS‐A). Both HADS‐T and HADS‐A showed unidimensionality. Our results supported the use of HADS‐T as a measure of psychological distress in PD patients. Moreover, the HADS‐A was also an adequate anxiety measure. Further research is required to address the use of HADS‐D in PD. © 2008 Movement Disorder Society     

Independent validation of SCOPA-psychosocial and metric properties of the PDQ-39 Brazilian version.

The objective of this study was to perform an independent validation of the Scales for Outcomes in Parkinson's Disease-Psychosocial questionnaire (SCOPA-PS) and assessment of the Parkinson's Disease Questionnaire (PDQ-39), Brazilian version. Patients were evaluated by means of the Unified Parkinson's Disease Rating Scale, Hoehn and Yahr staging (HY), Schwab and England scale, Mini-Mental State Examination, and Hospital Anxiety and Depression Scale. Health-related quality of life was evaluated using the MOS-Short Form 36 (SF-36), PDQ-39, and SCOPA-PS. One hundred forty-four patients were included (mean age, 62 years; 53.5% males; mean duration of illness, 6.6 years; HY, 1-4). Mean SCOPA-PS and PDQ-39 Summary Index (SI) were 39.2 and 40.7, respectively. The internal consistency of SCOPA-PS (Cronbach's alpha = 0.84; item-total correlation, 0.44-0.73) and PDQ-39 dimensions (alpha = 0.61-0.85; item-total correlation, 0.46-0.82) were satisfactory. Concerning the stability of the questionnaires, intraclass correlation coefficient (ICC) values were 0.71 for the SCOPA-PS and 0.86 for the PDQ-39 SI. ICC for PDQ-39 dimensions ranged from 0.52 (social support) to 0.80 (stigma). Standard error of measurement (SEM) values for each PDQ-39 dimension ranged from 0.49 (emotional well-being) to 17.52 (social support). SEM values for SCOPA-PS and PDQ-39 SI were 11.84 and 6.72, respectively. A significant correlation of SCOPA-PS and PDQ-39 SI with the SF-36 physical (-0.42 and -0.52, respectively) and mental components (-0.41) was found. Correlation between SCOPA-PS and PDQ-39 SI was 0.73 (all coefficients, P < 0.0001). The SCOPA-PS and PDQ-39, Brazilian versions, have satisfactory metric attributes.     

Reliability and validity of the Beck depression inventory in patients with Parkinson's disease.

We evaluated the validity, reliability, and potential responsiveness of the Beck Depression Inventory (BDI) in patients with Parkinson's disease (PD). In part 1 of the study, 92 patients with PD underwent a structured clinical interview for DSM major depression and based on this patients were considered depressed (PD-D) or nondepressed (PD-ND). Subsequently, patients filled in the BDI. In part 2, a postal survey consisting the BDI was performed in 185 PD patients and 112 controls. Test-retest reliability was assessed in 60 PD patients. The factor analysis revealed a cognitive-affective and a somatic factor. Cronbachs alpha for the BDI was 0.88. Mean BDI indicated significant differences (P<0.001) between the PD and control group, between the PD-ND and PD-D group, and between PD-ND and control group. In part 1, the receiver operating characteristic curves showed that the area under the curve for the total BDI was 0.88. A cutoff was calculated for the BDI (14/15) that had the highest sum of sensitivity (0.71) and specificity (0.90). In part 2, the test-retest reliability for the BDI total score was 0.89 (intraclass correlation coefficient). The smallest real difference was 3.3 for the total BDI. The BDI is a valid, reliable, and potential responsive instrument to assess the severity of depression in PD. However, an adjusted cutoff is recommended.     

Psychometric properties of the apathy evaluation scale in patients with Parkinson's disease

Parkinson's disease (PD) frequently entails non‐motor symptoms, worsening the course of the disease. Apathy is one of the core neuropsychiatric symptoms that has been investigated in recent years; research is however hampered by the limited availability of well‐evaluated apathy scales for these patients. We evaluated the psychometric properties of the Apathy Evaluation Scale (AES) in a sample of PD patients. Psychometric properties, convergent and discriminant validity and sensitivity/specificity were evaluated in patients with (n = 582) or without dementia/depression (n = 339). Internal consistency was high in the entire sample as well as in patients without dementia/depression. Correlations were moderate for convergent validity (UPDRS I item 4: motivation). While apathy could be differentiated from cognitive decline, it was related to depression (Geriatric Depression Scale, GDS‐15). The overall classification accuracy based on the UPDRS I item 4 was comparable for AES and GDS scores. The AES exhibits good psychometric properties in PD patients with and without dementia and/or depression. Commonly used screenings on the presence of apathy had low detection rates compared to the AES and reflected both apathetic and depressive symptoms. Psychometric evaluation of available instruments will support further research on the clinical relevance of apathy for disease progression and treatment approaches in PD patients.     

Burden,perceived health status,and mood among caregivers of Parkinson's disease patients

The objective of this study is to describe the characteristics of the caregivers of patients with Parkinson's disease (PD) and to analyze the association between these characteristics and caregiver burden, perceived health and mood status, and identify their predictors. A multicenter, nationwide, observational, cross‐sectional study that included 289 patient–caregiver pairs was conducted. Caregiver self‐assessments were the Hospital Anxiety and Depression Scale (HADS), EuroQol (EQ), and Zarit Caregiver Burden Inventory (ZCBI). Most caregivers in the study were women aged 60 years or thereabouts. Over two thirds were gainfully employed or housewives, 75% were patients' spouses, and the majority (96.5%) had been permanently taking care of the patient for 6 ± 5.4 years. Less than 5% of patients were in the most advanced stages of disease, and direct costs were 6,350 euros per patient per year. Caregivers had more mood disorders and worse health‐related quality of life (HRQol; EQ‐Tariff) than did the general population. Caregiver HADS and EuroQol scores displayed a weak correlation (r_S = 0.01–0.28) with patient‐related variables (disease duration, HY, SCOPA‐Motor, SCOPA‐AUT, HADS, PPRS, and CISI‐PD) whereas the ZCBI correlated moderately (r_S = 0.27–0.47). Among caregivers, the EQ‐Tariff was significantly lower and the HADS‐Anxiety scores significantly higher for women. ZCBI and HADS‐depression, though not EuroQol and HADS‐anxiety, scores significantly increased with increasing PD severity levels. Caregivers' affective status proved the most important factor influencing their burden and perceived health, whereas patient‐related variables influenced caregiver burden and mood but not health status. In PD, prevalence of affective disorders among patients' caregivers is high and influences both burden and HRQoL. © 2008 Movement Disorder Society     

Impaired bed mobility and disordered sleep in Parkinson's disease.

The contribution of impaired mobility to disordered sleep in Parkinson's disease (PD) remains uncertain. We evaluated the sleep of 38 people with PD and observed their turning strategies. Most reported difficulty maintaining sleep and difficulty turning. Those who hip-hitched rated themselves more disabled and those who sat up had more severe PD than those who used support. Using multiple strategies was associated with sleep disturbance. As the ability to turn deteriorates, we recommend patients identify the single strategy least disruptive to sleep. Research must address whether improving mobility improves sleep quality.     

Cognitive profile of Parkinson's disease patients: a comparative study between early-onset and late-onset Parkinson's disease

Aim: To investigate the influence of onset age on the occurrence and progression of cognitive dysfunction using neuropsychological tests and the electrophysiological component P300 in both early-onset Parkinson's disease (EOPD) and late-onset Parkinson's disease (LOPD) patients. Methods: A cohort of 76 EOPD patients and 166 LOPD patients was recruited for this study. Demographic information and clinical features, including age, disease duration, education level, family history, the Unified Parkinson's Disease Rating Scale, the Hoehn and Yahr stage, and depression scores were documented for each patient. The Mini-Mental State Examination, Montreal Cognitive Assessment (MoCA), Wechsler Adult Intelligence Scale – Revised, Chinese version (WAIS-RC) and Wechsler Memory Scale – Revised, Chinese version (WMS-RC) were used. In addition, P300 was also examined to assess cognitive function. Results: Although EOPD patients had longer disease duration, their cognitive dysfunction progressed more slowly. The MoCA tests revealed that EOPD patients had higher scores in visuospatial function, attention, delayed recall, and orientation than the LOPD patients. The difference between the two groups on the WMS-RC test did not reach significance, whereas the scores in executive function, visuospatial function and attention as measured on the WAIS-RC test were significantly lower in the LOPD group. In addition, P300 latencies were markedly delayed and P300 amplitudes were reduced in the LOPD group. Conclusions: The current findings demonstrated that cognitive dysfunction progressed more slowly in the EOPD group. Although the LOPD patients exhibited shorter disease durations, their cognitive abilities, including executive function, visuospatial function and attention, may have been impaired.     

Quality of life and related concepts in Parkinson's disease: a systematic review.

Several studies have investigated the quality of life (QOL) of patients with Parkinson's disease (PD). The purpose of this study was to review the conceptual and methodological quality of quality of life (QOL) studies among patients with PD and to identify factors associated with poor (HR)QOL. Computerized bibliographic databases were screened for publications from 1960 to January 2007. According to a list of predefined criteria, the methodological quality of the 61 studies, was moderate. The term 'QOL' was often used inappropriately. In fact, almost all studies in this review actually assessed health status (HS) instead of QOL. The functioning of patients with PD on physical, social, and emotional domains is affected by PD. Their HS seems to be lower when compared to healthy persons or patients with other chronic diseases. HS studies augment the insight in self-perceived functioning. Therefore, HS is conceived as a valuable construct. However, QOL is also an important factor in health care. Attention towards QOL is needed in order to draw valid conclusions regarding a person's subjective experience of well-being in a broad sense. In order to accomplish this, future studies should apply the QOL concept with more rigor, should use an adequate operational definition, and should employ sound measures.     

Development and testing of the Parkinson's disease quality of life scale.

We report on the development and results of preliminary psychometric testing of a disease specific health-related quality of life (HRQoL) scale intended for use in individuals diagnosed with idiopathic Parkinson's disease (PD). Results from an initial qualitative study provided content for item development and scale construction of the Parkinson's disease quality of life scale (PDQUALIF). The 33-item instrument includes seven domains: social/role function, self-image/sexuality, sleep, outlook, physical function, independence, and urinary function, plus one item of Global HRQoL. Initial psychometric testing of the instrument was conducted in 233 outpatient clinic attendees with physician-confirmed idiopathic PD. Factor structure, reliability and validity of the scale have been established in this cross-sectional study. Continuing development of the PDQUALIF will be directed at enhancing the psychometric properties, establishing responsiveness and determining appropriateness in culturally diverse samples.     

Acupuncture therapy for the symptoms of Parkinson's disease.

Interest in alternative medical treatments, including acupuncture, is increasing. Alternative treatments must be subjected to the same objective standards as all medical treatments. A non-blinded pilot study of the safety, tolerability, and efficacy of acupuncture (ACUPX) for the symptoms of (PD) was performed. Twenty PD patients (mean age, 68 years; disease duration, 8.5 years; Hoehn and Yahr [H&Y] stage, 2.2; Unified Parkinson's Disease Rating Scale score [UPDRS], 38.7) each received acupuncture treatments by a licensed acupuncturist. All patients were treated with two acupuncture treatment sessions per week. The first seven patients received 10 treatments and the last 13 patients 16 treatments. Patients were evaluated before and after ACUPX with the Sickness Impact Profile (SIP); UPDRS; H & Y; Schwab and England (S & E); Beck Anxiety Inventory (BAI); Beck Depression Inventory (BDI); quantitative motor tests, including timed evaluations of arm pronation supination movements, finger dexterity, finger movements between two fixed measured points, and the stand-walk-sit test; and a patient questionnaire designed for the study. Following ACUPX, there were no significant changes in the UPDRS, H&Y, S&E, BAI, BDI, quantitative motor tests, total SIP or the two SIP Dimension scores. Analysis of the 12 SIP categories not corrected for multiple comparisons revealed a post-ACUPX improvement in the sleep and rest category only (P = 0.03). On the patient questionnaire, 85% of patients reported subjective improvement of individual symptoms including tremor, walking, handwriting, slowness, pain, sleep, depression, and anxiety. There were no adverse effects. ACUPX therapy is safe and well tolerated in PD patients. A range of PD and behavioral scales failed to show improvement following ACUPX other than sleep benefit, although patients reported other discrete symptomatic improvements. A broad battery of tests in PD patients suggested that ACUPX resulted in improvement of sleep and rest only. This finding needs to be verified using more in-depth and controlled evaluation of ACUPX for PD-related sleep disturbance.     

Visual symptoms in Parkinson's disease and Parkinson's disease dementia

Visual symptoms are common in PD and PD dementia and include difficulty reading, double vision, illusions, feelings of presence and passage, and complex visual hallucinations. Despite the established prognostic implications of complex visual hallucinations, the interaction between cognitive decline, visual impairment, and other visual symptoms remains poorly understood. Our aim was to characterize the spectrum of visual symptomatology in PD and examine clinical predictors for their occurrence. Sixty-four subjects with PD, 26 with PD dementia, and 32 age-matched controls were assessed for visual symptoms, cognitive impairment, and ocular pathology. Complex visual hallucinations were common in PD (17%) and PD dementia (89%). Dementia subjects reported illusions (65%) and presence (62%) more frequently than PD or control subjects, but the frequency of passage hallucinations in PD and PD dementia groups was equivalent (48% versus 69%, respectively; P = 0.102). Visual acuity and contrast sensitivity was impaired in parkinsonian subjects, with disease severity and age emerging as the key predictors. Regression analysis identified a variety of factors independently predictive of complex visual hallucinations (e.g., dementia, visual acuity, and depression), illusions (e.g., excessive daytime somnolence and disease severity), and presence (e.g., rapid eye movement sleep behavior disorder and excessive daytime somnolence). Our results demonstrate that different "hallucinatory" experiences in PD do not necessarily share common disease predictors and may, therefore, be driven by different pathophysiological mechanisms. If confirmed, such a finding will have important implications for future studies of visual symptoms and cognitive decline in PD and PD dementia.     

Proxy reports in Parkinson's disease: caregiver and patient self-reports of quality of life and physical activity.

We evaluated patient-proxy agreement in a population of veterans with Parkinson's disease and compared levels of agreement by patient subgroups. Patient and caregiver pairs completed questionnaires composed of standard measures and additional demographic and activity questions. Participants completed the Center for Epidemiologic Studies Depression Scale (CES-D), the PD Questionnaire 39 (PDQ-39), and three questions regarding physical activity. Caregivers completed proxy forms of the PDQ-39 and the physical activity questionnaire. The proxy forms asked caregivers to choose the answers that best described their "friend's/patient's situation." The results of our comparison of patient and proxy reports of quality of life were consistent with findings in other diseases. On average, proxies rated patient disability higher and quality of life lower than did patients. However, our comparison of patient and proxy reports of frequency of exercise diverged from previously published work. Less agreement was observed between patient and proxy reports of physical activity, even though this is a more objective variable than are the domains measured by the PDQ-39. Proxy reports may diverge appreciably from patient self-reports. These differences should be considered in research design and clinical decision making. Alternative approaches to the measurement of patient relevant outcomes could supplement traditional, retrospective self-reports.