Hypertension later in life could protect against dementia

A new study published today by researchers at the University of California, Irvine found that the onset of high blood pressure later in life could be associated with lower dementia risk after the age of 90.

The study, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, found the risk of developing dementia is especially low if hypertension is developed at age 80 or older.

Researchers followed more than 550 people, aged 90 and older, for almost three years and examined the relationship between dementia, age at which hypertension developed and blood pressure levels. The participants, 69 percent of whom were female, did not have dementia when they enrolled in the study. Every six months, the researchers would assess the participants, and 224, or 40 percent, were diagnosed with dementia.

Results showed that study participants who had already developed hypertension from age 80 to 89 were 42 percent less likely to get dementia after 90 compared to those with no history of high blood pressure. Participants that developed hypertension at 90 or older were 63 percent less likely to develop dementia than those without hypertension.

"In this first-of-its-kind study, we find that hypertension is not a risk factor for dementia in people age 90 or over, but is actually associated with reduced dementia risk," said Maria Corrada, the lead author on the study and a professor of neurology and epidemiology at the University of California, Irvine. "This relationship had not yet been examined in groups of older people in their 80s or 90s, known as the 'oldest old.'"