R. Greenhall

Bio: R. Greenhall is an academic researcher from University of Oxford. The author has contributed to research in topics: SF-36 & Quality of life. The author has an hindex of 6, co-authored 7 publications receiving 2384 citations.

The Parkinson's Disease Questionnaire (PDQ-39): development and validation of a Parkinson's disease summary index score

Abstract: Objectives: to briefly outline the development and validation of the Parkinson's Disease Questionnaire (PDQ-39) and then to provide evidence for the use of the measure as either a profile of health status scores or a single index figure. Design: the PDQ-39 was administered in two surveys: a postal survey of patients registered with local branches of the Parkinson's Disease Society of Great Britain (n = 405) and a survey of patients attending neurology clinics for treatment for Parkinson's disease (n = 146). Data from the eight dimensions of the PDQ-39 were factor-analysed. This produced a single factor on the data from both surveys. Outcome measures: the eight dimensions of the PDQ-39 and the new single index score—the Parkinson's disease summary index (PDSI), together with clinical assessments (the Columbia rating scale and the Hoehn and Yahr staging score). Results: in the postal survey 227 patients returned questionnaires (58.2%). All 146 patients approached in the clinic sample agreed to take part. Higher-order principal-components factor analysis was undertaken on the eight dimensions of the PDQ-39 and produced one factor on both datasets. Consequently it was decided that the scores of the eight domains could be summed to produce a single index figure. The psychometric properties of this index were explored using reliability tests and tests of construct validity. The newly derived single index was found to be both internally reliable and valid. Discussion: data from the PDQ-39 can be presented either in profile form or as a single index figure. The profile should be of value in studies aimed at determining the impact of treatment regimes upon particular aspects of functioning and well-being in patients with Parkinson's disease, while the PDSI will provide a summary score of the impact of the illness on functioning and well-being and will be of use in the evaluation of the overall effect of different treatments. Furthermore, the PDSI reduces the number of statistical comparisons and hence the role of chance when exploring data from the PDQ-39.

The development and validation of a short measure of functioning and well being for individuals with Parkinson's disease.

Abstract: Parkinson's disease is a common degenerative neurological condition. A number of general health status measures exist but these may not address areas salient to specific diseases. We report here the development and validation of a short 39 item health status questionnaire for use in Parkinson's disease. Questionnaire items, generated from in-depth interviews with people with Parkinson's disease, were developed into a 65 item questionnaire. Data from a postal survey using the 65 item questionnaire were statistically analysed to produce a shorter questionnaire with 39 items and eight scales addressing different dimensions of Parkinson's disease. A second postal survey was conducted in order to assess the reliability and validity of the new 39 item questionnaire. The final questionnaire, referred to here as the 39 item Parkinson's Disease Questionnaire (PDQ-39), proved to have satisfactory internal and test-retest reliability, and construct validity in relation to other measures, reported by respondents with Parkinson's disease.

The PDQ-8: Development and validation of a short-form parkinson's disease questionnaire

Abstract: The Parkinson's Disease Questionnaire (PDQ-39) is a disease specific measure of health status which covers eight dimensions of ill-health, and contains 39 questions. The development of the question...

Self-reported Functioning and Well-being in Patients with Parkinson's Disease: Comparison of the Short-form Health Survey (SF-36) and the Parkinson's Disease Questionnaire (PDQ-39)

Abstract: The purpose of this paper was to document the impact of Parkinson's disease (PD) upon patients using both a generic health status measure (the Short-form 36 health survey questionnaire, SF-36) and a disease-specific measure (the 39-item Parkinson's Disease Questionnaire, PDQ-39). Comparing the results of the SF-36 in this population with a similar aged group selected randomly from two general practices it was evident that the disease has considerable impact on general levels of functioning and well-being. Furthermore, other areas not contained on the SF-36 were found to be relevant to PD patients. It is suggested that the disease-specific measure will be of value, ideally alongside a generic measure, in studies aimed at determining the impact of a treatment regimen upon PD patients, or to monitor the long-term progress of cohorts of patients with PD. The paper highlights the need for careful consideration of measures for evaluation.

Health-related quality of life in parkinson's disease: A study of outpatient clinic attenders

Abstract: Objective To assess the validity and responsiveness of a questionnaire to assess health-related quality of life in Parkinson's disease (PD)--the 39-item Parkinson's Disease Questionnaire (PDQ-39)--and to report problems experienced by patients by means of the questionnaire. Methods Patients completed the PDQ-39 and the SF-36 at baseline and 4 months later. At the same assessments, neurologists rated patients with Hoehn and Yahr and Columbia Scales. Results Evidence for validity of the new questionnaire was observed by agreement of scores with clinical scales at both assessments. Evidence for responsiveness of scales assessing physical function, particularly mobility and activities of daily living, was observed from significant paired t tests for differences between scores at baseline and follow-up, and correlations with patients' retrospective judgments and changes in the SF-36 summary scores. However, there were no significant associations with changes in neurologists' clinical scores. Patients most frequently reported problems of physical function in the PDQ-39. Scores for several dimensions of the PDQ-39 were significantly more favorable than those reported by nonclinic samples of patients with PD. Conclusions The PDQ-39 has validity for use among patients attending neurological clinics for treatment of PD. There is also some evidence of responsiveness. The questionnaire identifies problems that are important to patients and that appear to be more commonly experienced by nonclinic attenders.

A Randomized Trial of Deep-Brain Stimulation for Parkinson's Disease

Abstract: BACKGROUND: Neurostimulation of the subthalamic nucleus reduces levodopa-related motor complications in advanced Parkinson's disease. We compared this treatment plus medication with medical management. METHODS: In this randomized-pairs trial, we enrolled 156 patients with advanced Parkinson's disease and severe motor symptoms. The primary end points were the changes from baseline to six months in the quality of life, as assessed by the Parkinson's Disease Questionnaire (PDQ-39), and the severity of symptoms without medication, according to the Unified Parkinson's Disease Rating Scale, part III (UPDRS-III). RESULTS: Pairwise comparisons showed that neurostimulation, as compared with medication alone, caused greater improvements from baseline to six months in the PDQ-39 (50 of 78 pairs, P=0.02) and the UPDRS-III (55 of 78, P<0.001), with mean improvements of 9.5 and 19.6 points, respectively. Neurostimulation resulted in improvements of 24 to 38 percent in the PDQ-39 subscales for mobility, activities of daily living, emotional well-being, stigma, and bodily discomfort. Serious adverse events were more common with neurostimulation than with medication alone (13 percent vs. 4 percent, P<0.04) and included a fatal intracerebral hemorrhage. The overall frequency of adverse events was higher in the medication group (64 percent vs. 50 percent, P=0.08). CONCLUSIONS: In this six-month study of patients under 75 years of age with severe motor complications of Parkinson's disease, neurostimulation of the subthalamic nucleus was more effective than medical management alone. (ClinicalTrials.gov number, NCT00196911 [ClinicalTrials.gov].).

Non-motor symptoms of Parkinson's disease: diagnosis and management

Abstract: The clinical diagnosis of Parkinson's disease rests on the identification of the characteristics related to dopamine deficiency that are a consequence of degeneration of the substantia nigra pars compacta. However, non-dopaminergic and non-motor symptoms are sometimes present before diagnosis and almost inevitably emerge with disease progression. Indeed, non-motor symptoms dominate the clinical picture of advanced Parkinson's disease and contribute to severe disability, impaired quality of life, and shortened life expectancy. By contrast with the dopaminergic symptoms of the disease, for which treatment is available, non-motor symptoms are often poorly recognised and inadequately treated. However, attention is now being focused on the recognition and quantitation of non-motor symptoms, which will form the basis of improved treatments. Some non-motor symptoms, including depression, constipation, pain, genitourinary problems, and sleep disorders, can be improved with available treatments. Other non-motor symptoms can be more refractory and need the introduction of novel non-dopaminergic drugs. Inevitably, the development of treatments that can slow or prevent the progression of Parkinson's disease and its multicentric neurodegeneration provides the best hope of curing non-motor symptoms.

Movement Disorder Society Task Force report on the Hoehn and Yahr staging scale: status and recommendations.

Abstract: The Movement Disorder Society Task Force for Rating Scales for Parkinson's disease (PD) prepared a critique of the Hoehn and Yahr scale (HY). Strengths of the HY scale include its wide utilization and acceptance. Progressively higher stages correlate with neuroimaging studies of dopaminergic loss, and high correlations exist between the HY scale and some standardized scales of motor impairment, disability, and quality of life. Weaknesses include the scale's mixing of impairment and disability and its non-linearity. Because the HY scale is weighted heavily toward postural instability as the primary index of disease severity, it does not capture completely impairments or disability from other motor features of PD and gives no information on nonmotor problems. Direct clinimetric testing of the HY scale has been very limited, but the scale fulfills at least some criteria for reliability and validity, especially for the midranges of the scale (Stages 2-4). Although a "modified HY scale" that includes 0.5 increments has been adopted widely, no clinimetric data are available on this adaptation. The Task Force recommends that: (1) the HY scale be used in its original form for demographic presentation of patient groups; (2) when the HY scale is used for group description, medians and ranges should be reported and analysis of changes should use nonparametric methods; (3) in research settings, the HY scale is useful primarily for defining inclusion/exclusion criteria; (4) to retain simplicity, clinicians should "rate what you see" and therefore incorporate comorbidities when assigning a HY stage; and (5) because of the wide usage of the modified HY scale with 0.5 increments, this adaptation warrants clinimetric testing. Without such testing, however, the original five-point scales should be maintained.

Direct brain infusion of glial cell line–derived neurotrophic factor in Parkinson disease

Abstract: Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor with restorative effects in a wide variety of rodent and primate models of Parkinson disease, but penetration into brain tissue from either the blood or the cerebro-spinal fluid is limited. Here we delivered GDNF directly into the putamen of five Parkinson patients in a phase 1 safety trial. One catheter needed to be repositioned and there were changes in the magnetic resonance images that disappeared after lowering the concentration of GDNF. After one year, there were no serious clinical side effects, a 39% improvement in the off-medication motor sub-score of the Unified Parkinson's Disease Rating Scale (UPDRS) and a 61% improvement in the activities of daily living sub-score. Medication-induced dyskinesias were reduced by 64% and were not observed off medication during chronic GDNF delivery. Positron emission tomography (PET) scans of [(18)F]dopamine uptake showed a significant 28% increase in putamen dopamine storage after 18 months, suggesting a direct effect of GDNF on dopamine function. This study warrants careful examination of GDNF as a treatment for Parkinson disease.

What contributes to quality of life in patients with Parkinson's disease?

Abstract: Objective—To identify the factors that determine quality of life (QoL) in patients with idiopathic Parkinson’s disease in a population based sample. Quality of life (QoL) is increasingly recognised as a critical measure in health care as it incorporates the patients’ own perspective of their health. Methods—All patients with Parkinson’s disease seen in a population based study on the prevalence of parkinsonism were asked to complete a disease-specific QoL questionnaire (PDQ-39) and the Beck depression inventory. A structured questionnaire interview and a complete neurological examination, including the Hoehn and Yahr scale, the Schwab and England disability scale, the motor part of the unified Parkinson’s disease rating scale (UPDRS part III), and the mini mental state examination were performed by a neurologist on the same day. Results—The response rate was 78%. The factor most closely associated with QoL was the presence of depression, but disability, as measured by the Schwab and England scale, postural instability, and cognitive impairment additionally contributed to poor QoL. Although the UPDRS part III correlated significantly with QoL scores, it did not contribute substantially to predicting their variance once depression, disability, and postural instability had been taken into account. In addition, patients with akinetic rigid Parkinson’s disease had worse QoL scores than those with tremor dominant disease, mainly due to impairment of axial features. Conclusion—Depression, disability, postural instability, and cognitive impairment have the greatest influence on QoL in Parkinson’s disease. The improvement of these features should therefore become an important target in the treatment of the disease. (J Neurol Neurosurg Psychiatry 2000;69:308‐312)