Prognosis of Mild Cognitive Impairment in Early Parkinson Disease The Norwegian ParkWest Study Cognitive Impairment in Early Parkinson Disease

Pedersen K, Larsen J, Tysnes O, et al. — Wed, 01 May 2013 00:00:00 GMT

Importance

Mild cognitive impairment (MCI) is common in Parkinson disease (PD), but the prognostic value of MCI in early PD is unknown.

Objective

To examine the course of MCI and its progression to dementia in an incident PD cohort.

Design

Prospective longitudinal cohort study.

Setting

The Norwegian ParkWest study, an ongoing population-based study of the incidence, neurobiology, and prognosis of PD in western and southern Norway.

Participants

A population-based cohort of 182 patients with incident PD monitored for 3 years.

Main Outcomes and Measures

Serial neuropsychological tests of attention, executive function, verbal memory, and visuospatial skills were administered at baseline, 1 year, and 3 years. Patients were classified as having MCI and received a diagnosis of dementia according to published consensus criteria.

Results

Significantly more patients with MCI than without MCI at baseline (10 of 37 [27.0%] vs 1 of 145 [0.7%]; relative risk, 39.2 [95% CI, 5.2-296.5]; P < .001) progressed to dementia during follow-up. Of those with MCI at baseline, 8 of 37 (21.6%) had MCI that reverted to normal cognition during follow-up. Mild cognitive impairment at the 1-year visit was associated with a similar progression rate to dementia (10 of 36 patients [27.8%]) and reversion rate to normal cognition (7 of 36 [19.4%]). However, among the 22 patients with persistent MCI at baseline and the 1-year visit, 10 (45.5%) developed dementia and only 2 (9.1%) had MCI that reverted to normal cognition by the end of study.

Conclusions and Relevance

Mild cognitive impairment at PD diagnosis predicts a highly increased risk for early dementia. Repeated neuropsychological testing increases the prognostic accuracy of MCI with respect to early dementia development in PD.

Can Mild Cognitive Impairment in Parkinson Disease Predict the Development of Dementia? MCI in PD and the Development of Dementia

Copeland BJ, Schiess MC. — Wed, 01 May 2013 00:00:00 GMT

The term mild cognitive impairment (MCI) emerged in the 1990s, defining a transition state from normal cognitive function and forcing our appreciation of cognitive changes not attributable to age, education, sex, race, ethnicity, language, or culture, but rather to a well-defined disease process or related pathology. The acceptance of MCI as a precursor to dementia and its use in predicting progression to Alzheimer dementia, by identifying a profile of cognitive dysfunction unique to Alzheimer dementia and attributable to the disease process and related pathology, is well substantiated. Recently, subtypes of MCI have been described that may have individual predilections for various dementia types.

AMA Publishing Group: Mild Cognitive Impairment Topic Collection

Prognosis of Mild Cognitive Impairment in Early Parkinson Disease The Norwegian ParkWest Study Cognitive Impairment in Early Parkinson Disease

Can Mild Cognitive Impairment in Parkinson Disease Predict the Development of Dementia? MCI in PD and the Development of Dementia