Predictors of cognitive impairment in an early stage Parkinson's disease cohort

Abstract

The impact of Parkinson’s disease (PD) dementia is substantial and has major functional and socioeconomic consequences. Early prediction of future cognitive impairment would help target future interventions. The Montreal Cognitive Assessment (MoCA), the Mini-Mental State Examination (MMSE), and fluency tests were administered to 486 patients with PD within 3.5 years of diagnosis, and the results were compared with those from 141 controls correcting for age, sex, and educational years. Eighteen-month longitudinal assessments were performed in 155 patients with PD. The proportion of patients classified with normal cognition, mild cognitive impairment (MCI), and dementia varied considerably, depending on the MoCA and MMSE thresholds used. With the MoCA total score at screening threshold, 47.7%, 40.5%, and 11.7% of patients with PD were classified with normal cognition, MCI, and dementia, respectively; by comparison, 78.7% and 21.3% of controls had normal cognition and MCI, respectively. Cognitive impairment was predicted by lower education, increased age, male sex, and quantitative motor and non-motor (smell, depression, and anxiety) measures. Longitudinal data from 155 patients with PD over 18 months showed significant reductions in MoCA scores, but not in MMSE scores, with 21.3% of patients moving from normal cognition to MCI and 4.5% moving from MCI to dementia, although 13.5% moved from MCI to normal; however, none of the patients with dementia changed their classification. The MoCA may be more sensitive than the MMSE in detecting early baseline and longitudinal cognitive impairment in PD, because it identified 25.8% of those who experienced significant cognitive decline over 18 months. Cognitive decline was associated with worse motor and non-motor features, suggesting that this reflects a faster progressive phenotype.

Exercises With and Without Virtual Reality on Pain in Patients With Parkinson Disease: A Randomized, Controlled, Single-Blind Trial

“…In the present study, 76.86% of the patients, irrespective of the group they were in, presented scores below 26 points. This study is, however, similar to others and individuals with PD who present some alteration in cognitive function have frequently been found 13 . As the primary outcome of our study was pain intensity analyzed by means of VAS, a simple scale, but one whose applicability can be difficult for children and elderly persons to understand, it's possible that rather imprecise reports may have influenced the responses given by individuals, due to the subjective nature of describing an algic symptom.…”

Cognitive Function in Early and Advanced Parkinson’s disease

“…In a longitudinal study applying Level 1 criteria, 70% of newly diagnosed participants were cognitively stable, 19% cognitively declined and 11% improved over 36 months [26]. Similarly, a recent study of 155 patients with PD over 18 months showed significant reductions in MoCA scores, but not MMSE scores [27]. In the current study, we failed to find increasing incidence of PD-MCI in the advanced group.…”

The Effect of Creatine and Coenzyme Q10 Combination Therapy on Mild Cognitive Impairment in Parkinson's Disease

“…In addition, the MoCA has shown excellent performance in discriminating amnestic MCI (aMCI) from normal cognition among elderly people, with reported receiver operating characteristic (ROC) areas under the curve (AUCs) ranging from 0.82 to 0.95, sensitivity ranging from 78 to 97%, and specificity ranging from 60 to 87% [6]. A recent study reported a similar conclusion that the MoCA may be more sensitive than the MMSE in detecting early baseline and longitudinal cognitive impairments in PD [7]. In the Singapore population, the cutoff scores of 26/27 and 24/25 are used to detect aMCI and mild AD, respectively [8].…”