Assessing quality of life in Parkinson's disease: Can a short‐form questionnaire be useful?

Various instruments with good psychometric properties have been developed for the assessment of health-related quality of life (HRQoL) in Parkinson's disease, (PD); however, in everyday practice a brief questionnaire is needed for quick screening of patients. We present the process of development and validation of the Greek version of PD questionnaire-8 (PDQ-8(GrV)), which is an 8-item scale derived from a well-known measure for the evaluation of HRQoL in PD, the PD questionnaire (PDQ-39). PDQ-8 (GrV) was applied to 228 nondemented Greek PD patients. Data from PDQ-39 were also collected from these patients for comparisons between the total scores of the two scales. Detailed statistical analysis showed that PD-8(GrV) has psychometric properties analogous to its parent questionnaire.     

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.     

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.     

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.     

Bilateral subthalamic nucleus stimulation and quality of life in advanced Parkinson's disease.

We examined the impact of the subthalamic nuclei (STN) deep brain stimulation (DBS) on the health-related quality of life (QoL) of patients with advanced Parkinson's disease (PD). Seventeen consecutive patients with refractory motor fluctuations and dyskinesia were included in the study (mean age, 60.9 +/- 7.7 years [range, 43-74 years]; disease duration, 16.4 +/- 8.5 years [range, 7-38 years]; mean off-medication Hoehn and Yahr stage, 4.23 +/- 0.66 [range, 2.5-5]). Each patient's assessment was carried out using common rating scales, following the Core Assessment Program for Intracerebral Transplantation (CAPIT) protocol. Dyskinesia and emotional state were evaluated through the Abnormal Involuntary Movement Scale (AIMS) and the Hospital Anxiety and Depression Scale (HAD). QoL was assessed by means of the Parkinson's Disease Questionnaire Spanish version (PDQ-39). Significant benefit was obtained in the motor manifestations and complications of disease, as well as in the functional state and mood (P < 0.001). Some QoL dimensions (mobility and activities of daily living) and the PDQ-39 Summary Index (PDQ-39SI) showed a significant improvement (P < 0.001). Benefit was modest (P < 0.05) for three other domains (emotional well-being, stigma, bodily discomfort) and nil for the rest. There was no correlation between the change obtained in the QoL (PDQ-39SI) and in the other variables. As measured by the PDQ-39, STN-DBS significantly improves important aspects of QoL in patients with advanced PD.     

Quality of life in Polish patients with long-lasting Parkinson's disease.

The objective of this study was to evaluate possible relationships between quality of life (QoL) of Polish patients with long-lasting Parkinson's disease and various demographic and clinical factors. The study comprised 141 patients of Movement Disorders outpatient clinics in Warsaw and Gdansk with at least 5 years of the disease duration. Mean age of patients was 68.09 +/- 8.51 years, mean duration of disease was 11.87 +/- 5.14 years. To assess the quality of life, the Parkinson's Disease Questionnaire (PDQ-39) was used. Additional questions concerned duration of disease, initial and current treatment and expenses associated with therapy. Self-perceived symptoms of depression were in our study the most important factor determining QoL. Duration of the disease and expenses related to the treatment also have a significant impact on the QoL. Patient's age and presence of dyskinesia seem to be irrelevant to the quality of life.     

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.     

Rasagiline improves quality of life in patients with early Parkinson's disease.

The objective of this study was to determine the effects of rasagiline as monotherapy on quality of life (QOL) in patients with early Parkinson's disease (PD). Rasagiline, a potent, second-generation, irreversible, selective monoamine oxidase B inhibitor improves PD symptoms in patients with early PD. Patients with early untreated PD were randomly assigned to once-daily rasagiline 1 mg/day, rasagiline 2 mg/day, or placebo in a 6-month, double-blind trial (n=404). At the end of 6 months, patients entered the preplanned, active-treatment phase in which those receiving 1 mg/day and 2 mg/day of rasagiline continued on their previously assigned dosages and those receiving placebo switched to rasagiline 2 mg/day, while maintaining blinding to treatment assignments. QOL was measured with the Parkinson's Disease Quality of Life questionnaire (PDQUALIF) at 0, 14, 26, and 52 weeks after randomization. Analysis of the change in PDQUALIF scores from baseline to 6 months showed adjusted treatment effects (with 95% confidence interval) favoring rasagiline over placebo of -2.91 units (-5.19, -0.64, P=0.01) for the 1 mg/day group and -2.74 units (-5.02, -0.45, P=0.02) for the 2 mg/day. Subscore analysis attributed most of this benefit to the self-image/sexuality domain. At 12 months (n=266), with all groups receiving rasagiline for at least 6 months, no significant differences in PDQUALIF scores were seen between groups. Rasagiline improved QOL compared with placebo. This QOL improvement appears to be accounted for primarily by the symptomatic benefit of rasagiline.     

Health-related quality of life in patients with advanced Parkinson's disease treated with deep brain stimulation of the subthalamic nuclei.

Parkinson's disease (PD) is a progressive neurodegenerative disorder for which there is as yet no cure. It affects many aspects of patients' lives, only some of which can be monitored by available clinical rating scales. In the past decade, there has been a new emphasis on the use of health-related quality of life (HRQOL) measures to describe patient response to treatment. We describe patient-reported HRQOL in subjects who underwent bilateral deep brain stimulation (DBS) of the subthalamic nuclei (STN) for the treatment of PD, compared with a similar group of subjects who did not receive surgical treatment. A consecutive series of patients (n = 11) with advanced idiopathic PD were treated with DBS of the STN. This surgically treated group was compared prospectively with a similar group of patients (n =13) awaiting surgery. Self-reported HRQOL, measured by the Parkinson's Disease Questionnaire (PDQ-39) was evaluated at three time periods T(0), T(3), and T(6). The surgery group was evaluated according to the Unified Parkinson's Disease Rating Sale (UPDRS) before (T(0)), 3 (T(3)), and 6 months (T(6)) after surgery. HRQOL, UPDRS part II and III, duration of off periods, and dyskinesias improved significantly from T(0) to T(3) and from T(0) to T(6) for the surgery group but not for the nonsurgery group. Ten of the 11 patients treated with DBS of the STN reported a lower summary score (indicating better HRQOL) 6 months after surgery. The results of this prospective controlled study suggest that patients with advanced idiopathic PD treated with DBS of the STN obtain significant improvements in patient reported HRQOL and in clinical outcomes 3 and 6 months after surgery.     

Freezing of gait affects quality of life of peoples with Parkinson's disease beyond its relationships with mobility and gait.

The aim of this study was to examine the association between freezing of gait (FOG) and quality of life (QoL) in patients with Parkinson's disease (PD). PD patients (n = 118) completed the PDQ-39 (QoL) and FOG-Q questionnaires. Disease severity was assessed by the Hoehn and Yahr (H&Y) staging and the Unified Parkinson's Disease Rating Scale (UPDRS). The relations between those parameters were assessed using regression models. 66 men and 52 women (mean age 65.8 +/- 10.2 years, UPDRS total score 48.4 +/- 17.1, disease duration 8.5 +/- 5.8 years, H&Y stage 2.7 +/- 0.8) participated. FOG severity had a significant effect on QoL (P < 0.0015), accounting for disease severity assessed by UPDRS. Specifically, FOG severity was correlated with all the dimensions of the PDQ-39 except for stigma and social support, as follows: with mobility, bodily discomfort, activity of daily living (ADL) (P < 0.005 in all), with emotional, communication, and cognition (P < 0.05 in all). FOG severity (FOG-Q) was also found to affect a modified PDQ total score, without the mobility aspect (P = 0.0081). FOG should be viewed as a highly important symptom with regard to QoL of PD patients beyond its effect on gait and mobility. On the basis of the present results, special attention should be given to FOG in the treatment of patients with PD.     

Quality of life outcomes following surgical treatment of Parkinson's disease.

We assessed the impact of surgical treatment of Parkinson's disease on quality of life using generic quality of life instruments and utility scores. The Medical Outcomes Study short form health survey SF-36 and Parkinson's Disease Questionnaire PDQ-39 were used before and 3-6 months after surgery to assess quality of life, and the results were converted into utility valuations. Ninety-seven patients were studied; 33 underwent unilateral thalamotomy, 33 unilateral pallidotomy, 20 bilateral pallidotomy, six subthalamic nucleus (STN) lesions, four mixed lesions, and in one case bilateral STN stimulation. All dimensions of the SF-36 except role mental and mental health showed statistically significant improvement following surgery. The PDQ-39 recorded significant improvements in the mobility, stigma, and bodily discomfort dimensions. The rating scale and time trade-off scales showed statistically significant gains in utility of 8% and 3%, respectively. Gains were particularly marked in the bilateral pallidotomy group. Differences in patient characteristics and selection made direct comparisons between procedures unreliable. Quality of life in patients with advanced Parkinson's disease is amenable to measurement; such measurement provides tentative evidence of significant gains in quality of life following some neurosurgical procedures.     

Nonmotor symptoms are independently associated with impaired health‐related quality of life in Chinese patients with Parkinson's disease

We performed a cross‐sectional study of 82 Chinese patients with Parkinson's disease (PD) enrolled during an 18‐month period using a clinical interview to assess the prevalence of nonmotor symptoms (NMS), the association with disease severity and motor status, and the impact on patients' health‐related quality of life (Hr‐QoL). The patients' NMS, Hr‐QoL, disease severity, and motor status were assessed by the Nonmotor Symptoms Scale (NMSS), the 39‐item Parkinson's Disease Questionnaire (PDQ‐39), the modified Hoehn and Yahr staging scale (H&Y) and the Unified Parkinson's Disease Rating Scale part III (UPDRS III), respectively. We found that 100% of patients with PD presented with NMS. The NMSS significantly correlated with disease duration (Spearman's r_S = 0.276, P = 0.012), H&Y (r_S = 0.230, P = 0.038), and UPDRS III (r_S = 0.350, P = 0.001). Similarly, the PDQ‐39 SI significantly associated with the disease duration (r_S = 0.258, P = 0.019), H&Y (r_S = 0.340, P = 0.002), and UPDRS III (r_S = 0.453, P < 0.001). NMS domains that influenced the PDQ‐39 SI were sleep/fatigue, mood, gastrointestinal, urinary, and miscellaneous symptoms. This strongly suggested that the five domains played a key role in the manifestation of Hr‐QoL. NMSS explains more of the variability in Hr‐QoL than UPDRS III, when both are the model (stepwise multiple linear regression analysis R² change, 47.8% vs. 5.87%, respectively). Therefore, these findings demonstrate that NMS are independently and negatively associated with Hr‐QoL in PD and that improving NMS should be viewed as an important part in the management of PD. © 2010 Movement Disorder Society     

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.     

Neural networks associated with quality of life in patients with Parkinson's disease

IntroductionThe neural underpinnings of health-related quality of life in Parkinson's disease remain unclear. This study was conducted to unravel which motor and non-motor symptoms in Parkinson's disease influence health-related quality of life and reveal neural networks most likely linked to it.MethodsComprehensive clinical assessments were conducted for 247 Parkinson's disease patients and image analyses were performed for 181 patients. Clinical scores commonly used to assess various symptoms related to health-related quality of life were investigated. Factor and resting-state functional magnetic resonance imaging analyses were reviewed to reveal health-related quality of life-associated brain networks.ResultsThe Spearman's rank correlation coefficient for the Parkinson's disease Questionnaire-39 summary index was high in the Activities-specific Balance Confidence Scale, Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale part 2, Freezing of Gait Questionnaire, and Self-reported Autonomic Symptoms in Parkinson's disease. Multiple regression and Random Forest regression analyses indicated that health-related quality of life-associated factors were Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale part 1, Depression Rating Scales, and the above-mentioned scales. The resting-state functional magnetic resonance imaging analysis revealed decreased functional connectivity between the anterior cingulate cortex and right temporo-parietal junction as health-related quality of life worsened.ConclusionFear of falling, daily living activities, gait freezing, and autonomic dysfunction have notable effects on health-related quality of life in Parkinson's disease. Brain networks consisting of the anterior cingulate cortex and temporo-parietal junction may be associated with the emotion-related and social factors of health-related quality of life in Parkinson's disease.     

Effect of medical and surgical interventions on health-related quality of life in Parkinson's disease.

Motor-related parameters are the standard outcome parameters for treatment interventions. Nonetheless, subjective appraisals about the consequences of treatment on health-related quality of life (HRQoL) are meanwhile established and may uncover important aspects of interventions. We have reviewed the literature with a defined search strategy and collected 61 clinical trials, which have used HRQoL as a planned outcome parameter. The articles were rated similarly as for the Task Force report of the Movement Disorder Society on interventions for Parkinson's disease (PD), but the relevant outcome parameter was HRQoL. We found that unilateral pallidotomy, deep brain stimulation of the subthalamic nucleus, and rasagiline are efficacious to improve the HRQoL of PD patients. For many other interventions, the efficacy to improve HRQoL in the PD setting cannot be considered to be proven so far. HRQoL should be part of future trial designs and more research is necessary to understand the determinants of QoL in PD.     

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.