Utility of the new Movement Disorder Society clinical diagnostic criteria for Parkinson's disease applied retrospectively in a large cohort study of recent onset cases

Naveed Malek,Michael A Lawton,Katherine A Grosset,Nin Bajaj,Roger A Barker,Yoav Ben-Shlomo,David J Burn,Tom Foltynie,John Hardy,Huw R Morris,Nigel M Williams,Nicholas Wood,Donald G Grosset

doi:10.1016/j.parkreldis.2017.04.006

Abstract

ObjectiveTo examine the utility of the new Movement Disorder Society (MDS) diagnostic criteria in a large cohort of Parkinson's disease (PD) patients. MethodsRecently diagnosed (<3.5 years) PD cases fulfilling United Kingdom (UK) brain bank criteria in Tracking Parkinson's, a UK multicenter prospective natural history study were assessed by retrospective application of the MDS criteria. ResultsIn 2000 cases, 1835 (91.7%) met MDS criteria for PD, either clinically established (n = 1261, 63.1%) or clinically probable (n = 574, 28.7%), leaving 165 (8.3%) not fulfilling criteria. Clinically established cases were significantly more likely to have limb rest tremor (89.3%), a good l-dopa response (79.5%), and olfactory loss (71.1%), than clinically probable cases (60.6%, 44.4%, and 34.5% respectively), but differences between probable PD and ‘not PD’ cases were less evident. In cases not fulfilling criteria, the mean MDS UPDRS3 score (25.1, SD 13.2) was significantly higher than in probable PD (22.3, SD 12.7, p = 0.016) but not established PD (22.9, SD 12.0, p = 0.066). The l-dopa equivalent daily dose of 341 mg (SD 261) in non-PD cases was significantly higher than in probable PD (250 mg, SD 214, p < 0.001) and established PD (308 mg, SD 199, p = 0.025). After 30 months' follow-up, 89.5% of clinically established cases at baseline remained as PD (established/probable), and 86.9% of those categorized as clinically probable at baseline remained as PD (established/probable). Cases not fulfilling PD criteria had more severe parkinsonism, in particular relating to postural instability, gait problems, and cognitive impairment. ConclusionOver 90% of cases clinically diagnosed as early PD fulfilled the MDS criteria for PD. Those not fulfilling criteria may have an atypical parkinsonian disorder or secondary parkinsonism that is not correctly identified by the UK Brain Bank criteria, but possibly by the new criteria.

Highlights

The accurate diagnosis of Parkinson's disease (PD) assists patient management and healthcare planning, and the identification of effective new treatments, which is important for a disease with an increasing prevalence [1]
A clinical diagnosis of PD according to the Movement Disorder Society (MDS) criteria is based on: absolute exclusion criteria, red flags, and positive supportive criteria
We found that over 90% of patients, at an early disease stage and with cardinal motor features and a clinical diagnosis of PD, fulfilled the MDS criteria for PD at baseline, and a higher proportion was categorized as clinically established PD than clinically probable PD

Summary

Introduction

The accurate diagnosis of Parkinson's disease (PD) assists patient management and healthcare planning, and the identification of effective new treatments, which is important for a disease with an increasing prevalence [1]. Increased knowledge about PD and disorders that mimic it has allowed the development of new clinical Movement Disorder Society (MDS) diagnostic criteria [4]. A clinical diagnosis of PD according to the MDS criteria is based on: absolute exclusion criteria (which rule out PD), red flags (which must be counterbalanced by supportive criteria), and positive supportive criteria. These are combined to determine diagnostic certainty as clinically probable PD, or clinically established PD [4]. We classified and described the phenotype of cases recruited to an observational study of PD, according to fulfilment of the new MDS criteria [4]

Methods

Results

Conclusion