Loneliness and risk of dementia

Dementia incidence tripled in lonely older adults who otherwise would be expected to have relatively low risk based on age and genes, researchers found in a recent study.

Lonely older people under age 80 without an APOE4 allele had a threefold greater risk of dementia (adjusted HR 3.03, 95% CI 1.63-5.62) over 10 years than similar people who weren't lonely, reported Joel Salinas, MD, MBA, MSc, of NYU Grossman School of Medicine in New York City, and colleagues.

Regardless of age or APOE4 status, lonely older adults had a higher 10-year dementia risk compared with those who weren't lonely (adjusted HR 1.54, 95% CI 1.06-2.24).

Among people without dementia, loneliness was associated with poorer executive function, lower total cerebral volume, and greater white matter injury, the researchers wrote in Neurology.

The study provides Class I evidence that loneliness increases the 10-year risk of developing dementia.