Models for predicting risk of dementia: a systematic review

Background Information from well-established dementia risk models can guide targeted intervention to prevent dementia, in addition to the main purpose of quantifying the probability of developing dementia in the future. Methods We conducted a systematic review of published studies on existing dementia risk models. The models were assessed by sensitivity, specificity and area under the curve (AUC) from receiver operating characteristic analysis. Results Of 8462 studies reviewed, 61 articles describing dementia risk models were identified, with the majority of the articles modelling late life risk (n= 39), followed by those modelling prediction of mild cognitive impairment to Alzheimer's disease (n= 15), mid-life risk (n= 4) and patients with diabetes (n= 3). Age, sex, education, Mini Mental State Examination, the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological assessment battery, Alzheimer's Disease Assessment Scale-cognitive subscale, body mass index, alcohol intake and genetic variables are the most common predictors included in the models. Most risk models had moderate-to-high predictive ability (AUC>0.70). The highest AUC value (0.932) was produced from a risk model developed for patients with mild cognitive impairment. Conclusion The predictive ability of existing dementia risk models is acceptable. Population-specific dementia risk models are necessary for populations and subpopulations with different characteristics.