Memory and executive function impairment predict dementia in Parkinson's disease

Abstract

We analyzed the association of neuropsychological test impairment at baseline with the development of dementia in idiopathic Parkinson's disease (PD) patients. A cohort of nondemented PD patients from northern Manhattan, NY was followed annually with neurological and neuropsychological evaluations. The neuropsychological battery included tests of verbal and nonverbal memory, orientation, visuospatial ability, language, and abstract reasoning. The association of baseline neuropsychological tests scores with incident dementia was analyzed using Cox proportional hazards models. The analysis controlled for age, gender, education, duration of PD, and the total Unified Parkinson's Disease Rating Scale motor score at baseline. Forty-five out of 164 patients (27%) became demented during a mean follow-up of 3.7 +/- 2.3 years. Four neuropsychological test scores were significantly associated with incident dementia in the Cox model: total immediate recall (RR: 0.92, 95% CI: 0.87-0.97, P = 0.001) and delayed recall (RR: 0.73, 95% CI: 0.59-0.91, P = 0.005) of the Selective Reminding Test (SRT), letter fluency (RR: 0.87, 95% CI: 0.77-0.99, P = 0.03), and Identities and Oddities of the Mattis Dementia Rating Scale (RR: 0.85, 95% CI: 0.73-0.98, P = 0.03). When the analysis was performed excluding patients with a clinical dementia rating of 0.5 (questionable dementia) at baseline evaluation, total immediate recall and delayed recall were still predictive of dementia in PD. Our results indicate that impairment in verbal memory and executive function are associated with the development of dementia in patients with PD.

Dementia and mild cognitive impairment in patients with Parkinson's disease

“…It was observed that a higher schooling level was associated with a reduced risk in cognitive impairment, confirming earlier studies with PD patients 6,19 . Nevertheless longitudinal studies are required to elucidate the aspect of the "protective effect" of a higher level of formal education on the cognition of PD patients 19 .…”

“…various references can be found in the literature with respect to a relationship between dementia and the score obtained on the Unified Parkinson Disease Rating Scale, especially in the sub-score indicating predominantly dopaminergic dysfunction 6,8 .…”

“…In the various studies, the gravity of cognitive involvement varies from a discreet impairment restricted to specific domains 4,5 to severe dementia 1,2,3,6 . Recent studies have referred to mild cognitive impairment (MCI) in PD, as in other clinical conditions, this being clinically characterised as intermediary between normal cognition and dementia 5 .…”

Mild Cognitive Impairment and Parkinson’s Disease - Something to Remember

“…Longitudinal studies are crucial in terms of better describing these deficits and their significance for long-term prognosis. However, historically such studies have failed to give a consistent picture, implicating a number of different neuropsychological deficits as predictors of dementia in PD, including executive deficits, [18][19][20] poor verbal fluency, [20,21] visuospatial dysfunction, [20] and language and memory deficits [19,22]. This inconsistency is likely to relate to important methodological differences between these studies including the nature of the cohorts (hospital versus community-based), disease stage of patients included, and the choice of neuropsychological assessments.…”

Comorbid states in Parkinson’s disease: an effect of MAO-B inhibitors

“…Уже на этапе УКР при нейропсихологическом тестировании не менее чем у 50% пациентов выявляются нарушения зрительно-про-странственных функций и памяти [88,91]. Раннее нару-шение исполнительных функций и памяти является фак-тором риска развития деменции при БП [86,[92][93][94][95]. Ког-нитивный дефект при БП традиционно обозначают как подкорковый или лобно-подкорковый, в отличие от кор-кового дефекта при болезни Альцгеймера (БА) [96].…”