Inflammation is a normal physical response that protects people’s bodies and brains from injury. As people age, however, they experience heightened inflammation, which appears to cause damage to healthy brain tissue.

Researchers from Boston University School of Medicine studied more than 3,000 people who were enrolled in the Framingham Heart Study to understand how inflammation and genetic vulnerability might interact to increase risk for developing Alzheimer’s dementia. The research team evaluated blood measures of inflammation, incidences of a new diagnoses of dementia, and brain volumes over the course of this longitudinal study.

They found that chronic low-grade inflammation in volunteers who were carriers of the APOE-4 genetic risk for Alzheimer’s disease had an earlier[1]age onset of dementia.

Common age-related illnesses — such as heart disease, diabetes, pneumonia, and urinary tract infection — may lead to chronic inflammation throughout the body and in the brain.

These findings suggest that rigorous treatment of such illnesses, particularly in older adults with the APOE-4 genetic risk, may help to delay onset of dementia symptoms.