A new risk-assessment tool can help primary-care providers predict whether individuals aged 65 years or older are more likely to develop dementia, researchers at the University of California at San Francisco report.
Some items on the 15-point scale (e.g., older age, low scores on cognitive tests, and having a particular gene) are well-established risk factors. Others are less conventional (e.g., being underweight, abstaining from alcohol, a history of coronary bypass surgery).
The NIH-funded study involved 3,375 participants in the Cardiovascular Health Cognition Study, which is nested within a larger prospective, population-based project. All were aged 65 years or older at baseline with no evidence of dementia; 59% were women, and 15% were black (Neurology. 2009; published online ahead of print).
During six years of follow-up, 14% developed some type of dementia. Of these, 51% were diagnosed with Alzheimer’s disease, 13% with vascular dementia, 31% with mixed dementia, and 5% with some other form. Overall risk correlated with index scores, as 4.2% of subjects with low scores (0-3 points) developed dementia compared with 22.8% of those with moderate scores (4-7points) and 56.0% of those with high scores (8-15 points).
The researchers looked at many factors associated with mental decline before culling a final “late-life dementia risk index.” It includes age, poor cognitive test performance, BMI <18.5, one or more apolipoprotein E-ε4 alleles, cerebral MRI findings of white matter disease or ventricular enlargement, internal carotid artery thickening on ultrasound, history of coronary bypass surgery, slow physical performance (of tasks such as buttoning a shirt), and lack of alcohol consumption.
“This tool could be used in clinical settings to target prevention and intervention strategies toward high-risk individuals,” the researchers conclude. “The index could also be used to reassure those individuals whose risk is low or moderate.”