A simple nomogram to predict the onset of dementia in mild cognitive impairment: A retrospective study

Background Currently there is no effective treatment to reverse Alzheimer's disease, thus prevention is crucial. Patients with mild cognitive impairment (MCI) have higher rate of progression to dementia. Two commonly used cognitive tests, Mini-Mental State Examination (MMSE) and Clock Drawing Test (CDT), have only modest accuracy at predicting conversion from MCI to dementia, whereas other potentially predicting factors are difficult to implement in clinical practice. Objective The aim of this study was to assess the performance of a combination of simple cognitive tests and routine clinical data to predict onset clinical dementia over 3-year follow-up in a cohort of outpatients with MCI. Methods Medical history was collected, and an advanced neuropsychological assessment was performed at baseline and at follow-up. Results 98 participants were included (mean age 76.6 ± 4.5 years), and 49 developed dementia. Participants who developed dementia had significantly lower MMSE and CDT scores, as well as higher presence of hypercholesterolemia at the baseline evaluation. In the multivariate binary logistic regression analysis, the OR were 0.71 (CI95% 0.58–0.87) for MMSE, 0.77 (CI95% 0.65–0.93) for CDT, and 3.9 (CI95% 1.4–10.9) for hypercholesterolemia. The ROC curve combining these three factors obtained a value of AUC of 0.825 (CI95% 0.74–0.91). A nomogram was then developed for the risk of evolution from MCI to dementia at 3 years. Conclusions Combining history of hypercholesterolemia with CDT and MMSE tests, may result in a simple prediction model to predict the onset of dementia over 3 years.