How Much Do Vascular Risk Factors Contribute to Dementia?

Proportion of Risk Modifiable Through Conventional Risk Factors

By Peter A. McCullough, MD, MPH

If you are like me, you are wondering if you will develop dementia like your parents have, and when? A recent news piece by reporter Samantha Anderer caught my attention.

A decades-long study suggests that hypertension, diabetes, and smoking throughout midlife and early late-life could contribute to 22% to 44% of dementia cases that occur before 80 years of age.

The analysis involving nearly 12 300 US participants examined the role of these common, modifiable vascular risk factors in the development of dementia between 1987 and 2000. The proportion of dementia cases attributable to these factors increased over each decade of life from ages 45 to 74 years; after age 80, the factors explained only 2% to 8% of cases.

As time went on, diabetes and hypertension appeared to contribute more to dementia risk whereas smoking contributed less. Depending on age, the proportion of dementia cases attributable to these factors was higher in Black individuals, women, and people without the APOE ε4 allele—a genetic marker for Alzheimer disease.

“Assuming causal relationships, maintaining optimal vascular health across the life course could mitigate a sizeable proportion of dementia risk by 80 years,” the authors wrote in JAMA Neurology.