title: Predictors of cognitive decline in the early stages of Parkinson's disease: a brief cognitive assessment longitudinal study.
abstract: Our objectives were to perform a longitudinal assessment of mental status in early stage Parkinson's disease (PD) patients, with brief neuropsychological tests, in order to find predictive factors for cognitive decline. Sixty-one, early stage, and nondemented patients were assessed twice, over a 2-year interval, with a global cognitive test (mini-mental state examination (MMSE)) and a frontal function test (frontal assessment battery (FAB)) and motor function scales. Dementia and hallucinations were diagnosed according to the DSM-IV criteria. Cognitive function scores did not decrease significantly, except for FAB lexical fluency score. Four patients presented with dementia at followup. The MMSE score below cut-off, worse gait dysfunction, the nontremor motor subtype, and hallucinations were significantly related to dementia. Rigidity and speech dysfunction were related to dementia and a decrease in FAB scores. We can conclude that decline in the MMSE and FAB scores is small and heterogeneous in the early stages of PD. Scores below cut-off in the MMSE could be helpful to predict dementia. Nontremor motor deficits could be predictive factors for frontal cognitive decline and dementia.
authors.affiliation: Neurology Department, Hospital de Egas Moniz, CHLO, Rua da Junqueira 126, 1349-019 Lisbon, Portugal ; CEDOC and Neurology Department, Faculdade de Ciências Médicas (FCM), Universidade Nova de Lisboa (UNL), Campo dos Mártires da Pátria, 130, 1169-056 Lisbon, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Bugalho
authors.forename: Miguel
authors.initials: M
authors.lastname: Viana-Baptista