WEDNESDAY, Oct. 22, 2014 (HealthDay News) -- After weight-loss surgery, some patients may be at risk for developing severe headaches, a new study suggests.
In a small number of people, the surgery was associated with a condition known as spontaneous intracranial hypotension -- or low blood pressure in the brain. The condition can trigger headaches while standing that disappear when lying down. These headaches can be accompanied by nausea, vomiting, neck stiffness and difficulty concentrating, the researchers added.
But Dr. Mitchell Roslin, chief of bariatric surgery at Lenox Hill Hospital in New York City, said the study is too small to be able to draw any firm conclusions.
"You're talking about 11 people out of more than 300, and that's a low number," said Roslin, who had no part in the study. "The other thing that's strange is that these headaches showed up an average of 56.5 months after surgery, which is a long time.
"This would not be my concern if I was contemplating bariatric surgery," Roslin said.
The report was published online Oct. 22 in the journal Neurology.
Although it is not clear why this condition might develop after weight-loss surgery, the researchers speculated that significant weight loss alters pressure in the brain, which might uncover a pre-existing condition that causes fluid to leak from the spine and trigger severe headaches.
While the study showed an association between weight-loss surgery and an increased risk of severe headaches, it did not prove a cause-and-effect link.
For the study, a team led by Dr. Wouter Schievink, of Cedars-Sinai Medical Center in Los Angeles, studied 338 people with spontaneous intracranial hypotension. They compared these people with 245 people with unruptured intracranial aneurysms -- a weak spot in a blood vessel in the brain that can break and cause bleeding, another condition that can cause headaches.
The researchers found that 11 of those with spontaneous intracranial hypotension had weight-loss surgery, compared with two of those with intracranial aneurysms (3.3 percent versus 0.8 percent).
Among those who had weight-loss surgery, headaches started within three months to 20 years after the procedure.
Of the 11 people who had weight-loss surgery and spontaneous intracranial hypotension, treatment relieved the headaches in nine cases. Two patients continued to have headaches after treatment, the researchers found.
"It's important for people who have had bariatric surgery and their doctors to be aware of this possible link, which has not been reported before," Schievink said in a statement. "This could be the cause of sudden, severe headaches that can be treated effectively, but there can be serious consequences if misdiagnosed."
Dr. John Morton, chief of bariatric and minimally invasive surgery at Stanford University School of Medicine, noted that obesity increases pressure in the brain and is a more common cause of headaches.
"When you carry excess weight, you have increased pressure in the brain," Morton explained.
In some patients, that increased pressure leads to headaches and even blindness, which are actually relieved by weight-loss surgery, he noted.
Visit the U.S. National Library of Medicine for more on weight-loss surgery.