Marcello Moccia

BACKGROUND: The variability in the clinical phenotype of Parkinson's disease seems to suggest the existence of several subtypes of the disease. To test this hypothesis we performed a cluster analysis using data assessing both motor and non-motor symptoms in a large cohort of newly diagnosed untreated PD patients. METHODS: We collected data on demographic, motor, and the whole complex of non-motor symptoms from 100 consecutive newly diagnosed untreated outpatients. Statistical cluster analysis allowed the identification of different subgroups, which have been subsequently explored. RESULTS: The data driven approach identified four distinct groups of patients, we have labeled: 1) Benign Pure Motor; 2) Benign mixed Motor-Non-Motor; 3) Non-Motor Dominant; and 4) Motor Dominant. CONCLUSION: Our results confirmed the existence of different subgroups of early PD patients. Cluster analysis revealed the presence of distinct subtypes of patients profiled according to the relevance of both motor and non-motor symptoms. Identification of such subtypes may have important implications for generating pathogenetic hypotheses and therapeutic strategies.

BACKGROUND: Cognitive impairment occurs from the early phases of multiple sclerosis (MS), and more frequently affects secondary progressive (SP) subjects than relapsing-remitting (RR). OBJECTIVE: To investigate relationships between cognitive dysfunctions in newly diagnosed RRMS, and long-term MS-related outcomes. METHODS: The present 10-year retrospective longitudinal study included 155 RRMS subjects, tested with the Rao Brief Repeatable Battery at MS diagnosis. The reaching of Expanded Disability Status Scale (EDSS) 4.0, and the SP conversion were recorded. RESULTS: 67 subjects (43.2%) reached EDSS 4.0, and 34 subjects (21.9%) converted to SP during a follow-up period of 10.0±1.8 years. Subjects with cognitive impairment at diagnosis had a rate of reaching EDSS 4.0 more than three times greater (p<0.001; HR=3.183), and a rate of SP conversion more than two times greater, as compared to cognitively preserved subjects (p=0.008; HR=2.535). In particular, better scores in the Selective Reminding Test-Delayed Recall and in the Symbol Digit Modalities Test at baseline were associated with lower SP conversion rates during the follow-up period (p=0.018; HR=0.835; and p=0.001; HR=0.941, respectively). CONCLUSION: Cognitive impairment, with particular involvement of processing speed and memory, predicts disability progression and SP conversion in newly diagnosed RRMS, highlighting the importance of cognitive assessment from the beginning of MS.