Basics of qualitative research: Grounded theory procedures and techniques

Objective: Parkinson’s disease (PD) is a progressive neurological disorder characterised by a large number of motor and non-motor features that can impact on function to a variable degree. This review describes the clinical characteristics of PD with emphasis on those features that differentiate the disease from other parkinsonian disorders. Methods: A MedLine search was performed to identify studies that assess the clinical characteristics of PD. Search terms included “Parkinson’s disease”, “diagnosis” and “signs and symptoms”. Results: Because there is no definitive test for the diagnosis of PD, the disease must be diagnosed based on clinical criteria. Rest tremor, bradykinesia, rigidity and loss of postural reflexes are generally considered the cardinal signs of PD. The presence and specific presentation of these features are used to differentiate PD from related parkinsonian disorders. Other clinical features include secondary motor symptoms (eg, hypomimia, dysarthria, dysphagia, sialorrhoea, micrographia, shuffling gait, festination, freezing, dystonia, glabellar reflexes), non-motor symptoms (eg, autonomic dysfunction, cognitive/neurobehavioral abnormalities, sleep disorders and sensory abnormalities such as anosmia, paresthesias and pain). Absence of rest tremor, early occurrence of gait difficulty, postural instability, dementia, hallucinations, and the presence of dysautonomia, ophthalmoparesis, ataxia and other atypical features, coupled with poor or no response to levodopa, suggest diagnoses other than PD. Conclusions: A thorough understanding of the broad spectrum of clinical manifestations of PD is essential to the proper diagnosis of the disease. Genetic mutations or variants, neuroimaging abnormalities and other tests are potential biomarkers that may improve diagnosis and allow the identification of persons at risk.

https://jnnp.bmj.com/content/jnnp/79/4/368.full.pdf

Parkinson’s disease: clinical features and diagnosis

This document presents the Movement Disorder Society Clinical Diagnostic Criteria for Parkinson's disease (PD). The Movement Disorder Society PD Criteria are intended for use in clinical research but also may be used to guide clinical diagnosis. The benchmark for these criteria is expert clinical diagnosis; the criteria aim to systematize the diagnostic process, to make it reproducible across centers and applicable by clinicians with less expertise in PD diagnosis. Although motor abnormalities remain central, increasing recognition has been given to nonmotor manifestations; these are incorporated into both the current criteria and particularly into separate criteria for prodromal PD. Similar to previous criteria, the Movement Disorder Society PD Criteria retain motor parkinsonism as the core feature of the disease, defined as bradykinesia plus rest tremor or rigidity. Explicit instructions for defining these cardinal features are included. After documentation of parkinsonism, determination of PD as the cause of parkinsonism relies on three categories of diagnostic features: absolute exclusion criteria (which rule out PD), red flags (which must be counterbalanced by additional supportive criteria to allow diagnosis of PD), and supportive criteria (positive features that increase confidence of the PD diagnosis). Two levels of certainty are delineated: clinically established PD (maximizing specificity at the expense of reduced sensitivity) and probable PD (which balances sensitivity and specificity). The Movement Disorder Society criteria retain elements proven valuable in previous criteria and omit aspects that are no longer justified, thereby encapsulating diagnosis according to current knowledge. As understanding of PD expands, the Movement Disorder Society criteria will need continuous revision to accommodate these advances.

/pdf/mds-clinical-diagnostic-criteria-for-parkinson-s-disease-74dzuucoq6.pdf

MDS clinical diagnostic criteria for Parkinson's disease

中枢神経系疾患の治療は正常細胞（ニューロン）の機能維持を目的とするが，脳血管障害のように機能障害の原因が細胞の死滅に基づくことは多い．一方，脳腫瘍の治療においては薬物療法や放射線療法といった腫瘍細胞の死滅を目標とするものが大きな位置を占める．いずれの場合にも，細胞死の機序を理解することは各種病態や治療法の理解のうえで重要である．現在のところ最も研究の進んでいる細胞死の型はアポトーシスである．そのなかで重要な位置を占めるミトコンドリアにおける反応および抗アポトーシス因子について概要を紹介する．

Neuroscience 細胞死：最近の知見

The Dementia with Lewy Bodies (DLB) Consortium has refined its recommendations about the clinical and pathologic diagnosis of DLB, updating the previous report, which has been in widespread use for the last decade. The revised DLB consensus criteria now distinguish clearly between clinical features and diagnostic biomarkers, and give guidance about optimal methods to establish and interpret these. Substantial new information has been incorporated about previously reported aspects of DLB, with increased diagnostic weighting given to REM sleep behavior disorder and 123iodine-metaiodobenzylguanidine (MIBG) myocardial scintigraphy. The diagnostic role of other neuroimaging, electrophysiologic, and laboratory investigations is also described. Minor modifications to pathologic methods and criteria are recommended to take account of Alzheimer disease neuropathologic change, to add previously omitted Lewy-related pathology categories, and to include assessments for substantia nigra neuronal loss. Recommendations about clinical management are largely based upon expert opinion since randomized controlled trials in DLB are few. Substantial progress has been made since the previous report in the detection and recognition of DLB as a common and important clinical disorder. During that period it has been incorporated into DSM-5, as major neurocognitive disorder with Lewy bodies. There remains a pressing need to understand the underlying neurobiology and pathophysiology of DLB, to develop and deliver clinical trials with both symptomatic and disease-modifying agents, and to help patients and carers worldwide to inform themselves about the disease, its prognosis, best available treatments, ongoing research, and how to get adequate support.

/pdf/diagnosis-and-management-of-dementia-with-lewy-bodies-fourth-bauvdvbrlh.pdf

Diagnosis and management of dementia with Lewy bodies Fourth consensus report of the DLB Consortium

Background: patients with Parkinson's disease (PD) have a high risk of sustaining osteoporotic fractures as a result of falls and reduced bone mass. Objective: to summarise the underlying pathophysiological mechanisms of bone loss in PD by reviewing the available literature. Methods: a Medline search was performed for articles published between January 1975 and January 2011, using the keywords 'bone mineral density', 'bone loss', 'bone metabolism', 'osteoporosis', 'osteopenia', 'Parkinson's disease' and 'Parkinsonism'. Results: PD patients have a lower bone mineral density (BMD) than age-matched controls. Bone loss in PD is multifactorial, resulting from immobility, decreased muscle strength, and low body weight. Vitamin D deficiency is also important, not only because it reduces BMD, but also because cell function in the substantia nigra depends on vitamin D. Lastly, hyperhomocystei- naemia, an independent risk factor for osteoporosis, is common in PD, due to levodopa use, as well as vitamin B12 and folic acid deficiency. A few studies have demonstrated that treatment with bisphosphonates, vitamin D and calcium can increase BMD and reduce fractures in PD patients. Conclusion: bone loss in PD is multifactorial. It is clinically important because of the concomitant risk of fractures. Screening for osteoporosis should be considered more often, and therapeutic interventions should be initiated.

Parkinson's disease and osteoporosis

Summary Background A multidisciplinary approach is thought to be the best way to manage the motor and non-motor symptoms of Parkinson's disease, but how such care should be delivered is unknown. To address this gap in knowledge, we assessed the effectiveness of an integrated multidisciplinary approach compared with usual care. Methods We recruited patients for our non-randomised controlled trial from six community hospitals in the Netherlands (two in regions where the integrated care intervention was available and four in control regions that administered usual care). Eligible patients were those with Parkinson's disease, aged 20–80 years, and without severe cognitive impairment or comorbidity. Patients in the intervention group were offered an individually tailored comprehensive assessment in an expert tertiary referral centre and subsequent referrals to a regional network of allied health professionals specialised in Parkinson's disease. Primary outcomes were activities of daily living (Academic Medical Center linear disability score [ALDS]) and quality of life (Parkinson's disease quality of life questionnaire [PDQL]) measured at 4, 6, and 8 months. Secondary outcomes included motor functioning (unified Parkinson's disease rating scale, part III [UPDRS III], at 4 months), caregiver burden (belastungsfragebogen Parkinson angehorigen–kurzversion [BELA-A-k] at 4 and 8 months), and costs (during whole study period). Primary analysis was by intention to treat and included scores over 4, 6, and 8 months, with correction for baseline score. The trial is registered at Clinicaltrials.gov, number NCT00518791. Findings We recruited 301 patients (150 patients in the intervention group and 151 in the control group) between August, 2007, and December, 2009, of whom 285 completed follow-up (last follow-up was July, 2010). 101 (67%) patients in the intervention group visited the expert centre; 49 (33%) opted not to visit the expert centre. The average ALDS score from months 4, 6, and 8, with correction for baseline score, was greater in the intervention group than in the control group (difference 1·3 points, 95% CI −2·1 to 2·8; corresponding raw logit score difference 0·1, 95% CI 0·003 to 0·2) as was the average PDQL score (difference 3·0 points, 0·4 to 5·6). Secondary analysis with correction for baseline disease severity showed no differences between groups for ALDS (difference 0·9 points, 95% CI −0·6 to 2·4; corresponding raw logit score difference 0·1, −0·02 to 0·3) or PDQL (difference 1·7 points, −1·2 to 4·6). Secondary outcomes did not differ between groups (UPDRS III score difference 0·6 points, 95% CI −1·4 to 2·6; BELA-A-k score difference 0·8 points, −0·2 to 1·8; cost difference €742, −€489 to €1950). Interpretation This integrated care approach offered only small benefits to patients with Parkinson's disease, and these disappeared after correction for baseline disease severity. These results suggest that different approaches are needed to achieve more substantial health benefits. Funding NutsOhra Foundation, Stichting Parkinson Nederland, National Parkinson Foundation.

https://www.thelancet.com/pdfs/journals/laneur/PIIS1474-4422(13)70196-0.pdf

Integrated multidisciplinary care in Parkinson's disease: a non-randomised, controlled trial (IMPACT).

Weight loss in neurodegenerative disorders

We retrospectively and prospectively assessed the frequency and characteristics of falls in patients with degenerative cerebellar ataxias. The results show that falls occur very frequently in patients with degenerative cerebellar ataxias and that these falls are serious and often lead to injuries or a fear of falling. Clinicians should be aware of this problem in ataxia patients and should try to prevent falls.

Bastiaan R. Bloem

Papers

Parkinson's disease and osteoporosis

Integrated multidisciplinary care in Parkinson's disease: a non-randomised, controlled trial (IMPACT).

Weight loss in neurodegenerative disorders

Falls in degenerative cerebellar ataxias

Disentangling the contribution of the paretic and non-paretic ankle to balance control in stroke patients