A Shock or Startle
Although seemingly insignificant, a simple startle was enough to increase risk of rupture by 23.3 times -- the most significant trigger found in the study. There's not a whole lot doctors can advise patients regarding this particular trigger -- "how can you avoid life?" says Dr. James Ausman at UCLA Medical Center.
Staying away from scary movies and fun houses might not hurt though.
Getting Worked Up
Anger was the only emotional trigger of significance, the researchers found. Study participants were 6.3 times more likely to suffer a rupture if they got worked up about something in the hour preceding it.
Anger may also tie into general prevention advice among those at risk for aneuryism. They should limit stress, says Aziz. To Marks, who's an actress and had been on stage countless times before her karaoke performance in Scotland, it seemed unlikely that stress had caused her aneuryism to rupture. "How many thousands of times I've been onstage," Marks recounts, "I don't know why that one time would have been different, but I don't know."
Blowing Your Nose
Blowing one's nose increased the risk of rupture 2.4-fold. Aziz said this was often true as well for coughing, because both activities increase pressure inside the skull, which in turn increases the chance that the weakened artery will burst.
Straining on the Toilet
Last but not least, straining on the toilet while constipated was another common risk factor, both in the study and anecdotally among doctors who treat aneurysms. It was also one of the few that doctors recommend treating in those with identified aneurysms.
"We think it is feasible to advise persons with [brain aneurysms] to refrain from coffee drinking and to use laxatives when constipated," says Algra.