Montreal Parkinson Risk of Dementia Scale Deemed Accurate

A study published in JAMA Neurology has found the Montreal Parkinson Risk of Dementia Scale to be a valid predictor of development of dementia, reports Medical Xpress . The researchers conducted a multicenter study employing four Parkinson's disease cohorts with a prospective 4.4-year follow-up to gauge the predictive validity of the scale, using 717 people with Parkinson's. A total of 607 were dementia-free at baseline and followed for at least 12 months. All eight items of the scale were found to independently predict dementia development. In the high-risk group the yearly conversion rate to dementia was 14.9 percent, versus 5.8 percent and 0.6 percent in the intermediate- and low-risk groups. The overall predictive validity by the area under the receiver operator characteristic curve was 0.877 across all cohorts. Sensitivity was 77.1 percent and specificity 87.2 percent for a cut-off of 4 or higher, with positive and negative predictive values of 43.9 percent and 96.7 percent, respectively. Positive and negative likelihood ratios were 5.94 and 0.26, respectively. Correlations were observed for scale results with makers of Alzheimer's pathology and neuropsychological test results. "Future studies using head-to-head comparisons or refinement of weighting would be of interest," the researchers believe.