Vasectomy may be a risk factor for rare form of dementia

Researchers at Northwestern University’s Feinberg School of Medicine, Chicago, have discovered that men who have had a vasectomy may be at increased risk for developing primary progressive aphasia (PPA), an irreversible neurologic disorder that causes patients to lose the ability to use and comprehend words.

Researchers surveyed 47 men with PPA who were being treated at the university’s Cognitive Neurology and Alzheimer’s Disease Center and 57 volunteers with no cognitive impairment. They ranged from 55 to 80 years old. After adjusting for age, investigators found that 40% of men with PPA had undergone a vasectomy compared with 16% of the non-impaired men (p=.02).

“That’s a huge difference,” said senior author Sandra Weintraub, PhD. “It doesn’t mean having a vasectomy will give you this disease, but it may be a risk factor to increase your chance of getting it.”

In addition, the men who had undergone a vasectomy developed PPA at a younger age than did men who had not had a vasectomy (58.8 vs. 62.9 years, p=.03). Dr. Weintraub theorizes that a vasectomy may raise the risk of PPA because the surgery may allow sperm to enter the blood stream, generating production of anti-sperm antibodies that could permeate the blood-brain barrier.

The findings were published in Cognitive and Behavioral Neurology (2006; 19:190-3).