Decades ago, hundreds of nuns and priests made an extraordinary decision: They agreed to donate their brains upon death to science, hoping to help solve mysteries about Alzheimer’s and other diseases. Now, a study that used their gifts is giving some clues. It reveals that high blood pressure late in life might harm the brain.
Autopsies on nearly 1,300 older people, including about 640 clergy members, found more signs of damage and one of the hallmarks of Alzheimer’s disease in the brains of those with higher blood pressure than among those with pressure closer to normal, researchers reported Wednesday.
The study does not prove cause and effect, and it does not yet provide a comparison of rates of dementia or its most common form, Alzheimer’s — those results will take longer to parse. But it challenges a theory that high pressure is not as harmful in old age as it is when people are younger.
“We can’t be alarmist. This is preliminary data” that needs to be validated by others, said the study leader, Dr. Zoe Arvanitakis of Rush University Medical Center in Chicago. “It’s far too soon to make recommendations about blood pressure in older people based on this study.”
The research began in 1994 and combined people from three studies of aging who agreed to donate their brains for autopsy upon their death, including the Religious Orders Study of Catholic clergy throughout the United States. All were over 65 and without known dementia at the start and were followed until they died — at an average age of 89 and after an average of eight years in the study.