Researchers at Northwestern University have discovered a link between vasectomy surgery and a form of dementia that usually strikes men in their 40's and 50's.
Known as Primary Progressive Aphasia (PPA), the disease targets the language center of the brain, causing victims to have difficulty remembering and understanding words. People afflicted with PPA lose the ability to talk and understand speech, and gradually deteriorate in other areas of function until they are fully incapacitated.
Lead researcher Dr. Sandra Weintraub, professor of psychiatry and behavioral sciences and or neurology at Northwestern's Feinberg School of Medicine, discovered a potential link between the disease and vasectomy surgery during a regular support meeting for PPA patients. One man who had developed language problems at age 43 referenced the start of his difficulty to the period following his surgery for vasectomy. He asked the nine men in the group who were suffering from PPA how many had undergone a vasectomy, and eight of the nine said they had.
Weintraub led a team of researchers who surveyed 47 men aged 55 to 80 with language-based dementia and found that 40% had undergone vasectomies, compared to 16% of the control group who did not have cognitive impairment.
"That's a huge difference," Weintraub said. "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."
Men who had a vasectomy and developed the disease showed symptoms at a younger age (58 years) than men who developed PPA without having the surgery (62 years).
A second form of early-onset dementia also seemed to be linked to vasectomy surgery, the study found, with preliminary results showing 37% ercent of men with frontotemporal dementia had undergone a vasectomy. The results were taken from a small group of 30 men and require further research to confirm a link.
Weintraub speculated that the disease may be triggered in part by antibodies formed in the blood of men who have vasectomies — during surgery the natural barrier designed to keep blood-born pathogens away from semen is breached, and sperm can enter the blood system. In 60 to 70% of cases, the body will react to the sperm as invasive and produce antibodies against it, which may then breach the blood-brain barrier and lead to the onset of PPA.
Weintraub plans to launch a national study to show if her preliminary results will be consistent in a larger population.
In a study released last June, a team of Thai researchers found a rate of severe chromosomal abnormality 10 times higher than normal in sperm taken from men with vasectomies. Sperm production continues after the surgery, leading to a build up of old, disintegrating sperm within the epididymus. Scarring and occasional rupture of the epididymus frequently occur, with further sperm breakdown.
While chromosomal abnormality rates did improve somewhat over time when the man under went a vasectomy reversal, researchers found chromosomal malformation rates remained abnormally high.