A new study has demonstrated that untreated high blood pressure is associated with an increased risk of Alzheimer’s disease in adults aged 60 and older.
The research The findings were published online Wednesday in the medical journal Neurology, published by the American Academy of Neurology. This is a review of 14 international studies involving 31,250 people.
Participants, whose average age was 72, were followed for approximately four years for changes in cognitive function and dementia diagnoses.
Of those surveyed, 1,415 developed Alzheimer’s disease.
The researchers found that participants with untreated high blood pressure were at higher risk for Alzheimer’s disease compared with those treated for high blood pressure and those without any chronic conditions.
“High blood pressure is a leading cause of stroke and cerebrovascular disease, but it can be controlled with medication to reduce the risk of these diseases,” said study author Matthew J. Lennon, PhD, of the University of New South Wales in Australia. “Our meta-analysis looked at older adults and found that untreated blood pressure may actually increase the risk.”
Lennon and his team analyzed participants’ blood pressure measurements, hypertension diagnoses, and medication use: 36% did not have high blood pressure, 51% were taking blood pressure medication, and 9% had untreated hypertension.
The researchers found that participants with untreated high blood pressure had a 36% higher risk of Alzheimer’s disease compared to people without high blood pressure, and a 42% higher risk of Alzheimer’s disease compared to participants who were medicated for high blood pressure.
The researchers emphasized that their findings do not prove that untreated high blood pressure causes Alzheimer’s disease, but only show an association.
“Our meta-analysis of people from around the world found that taking blood pressure medications reduces the risk of Alzheimer’s disease throughout old age,” Lennon said. “These results suggest that treating high blood pressure in older age continues to be an important factor in reducing the risk of Alzheimer’s disease.”
Lennon and his team note that a limitation of their study is that definitions of hypertension vary from country to country, and this inconsistency may lead to misdiagnosis.
Still, the findings support previous research suggesting that high blood pressure in older people can damage the brain: In autopsies, people with high blood pressure showed more signs and hallmarks of Alzheimer’s disease deterioration in their brains than those with closer to normal blood pressure.
Experts say about 70 percent of Americans will develop high blood pressure at some point, but only 25 percent are able to control it.
According to the Alzheimer’s Association, approximately 6.7 million Americans over the age of 65 have Alzheimer’s disease.
The new report comes on the heels of the Food and Drug Administration’s recent decision to approve two drugs shown to slightly slow the progression of Alzheimer’s, offering new options for patients in the early stages of the incurable disease that destroys memory and thinking skills.
