New research published in Neurology suggests bariatric surgery may be a risk factor for spontaneous intracranial hypotension – a condition that causes severe headaches.
The classic symptom of spontaneous intracranial hypotension (SIH) is severe headache when upright, which is relieved when the patient is lying down flat. Some people also get nausea, vomiting, double vision or difficulty with concentration.
When someone has SIH, they have negative pressure within their brain cavity. This can be caused by cerebrospinal fluid (CSF) leaking from the spinal canal and can happen following a shunt procedure for hydrocephalus (sometimes known as water on the brain), where a flexible tube is placed in the brain to reroute the flow of CSF.
Although SIH can be detected based on the nature of the headache and how it correlates with posture, it is usually not suspected for some time, and identifying where CSF is leaking from in the spinal cord can be very challenging.
When the leak has been identified, surgery may be required to repair the defect.
Bariatric – or “gastric bypass” – surgery is a type of weight loss surgery. The procedure involves the patient’s stomach being stapled into forming a smaller pouch that only holds about 1 oz of food, and a new connection being made between this pouch and the small intestine.
Bariatric surgery makes the patient eat less and absorb fewer calories, which causes them to lose weight.
- Other risks linked with bariatric surgery include breathing problems, heart attack or stroke after the surgery
- Bariatric surgery is not “a quick fix” for obesity, and patients must continue to diet and exercise following surgery
- Patients will only receive bariatric surgery if they are unable to lose a large amount of weight and keep it off by dieting and exercising.
In the new study, researchers from Cedars-Sinai Medical Center in Los Angeles, CA, compared a group of 338 people with SIH with a control group of 245 people with unruptured intracranial aneurysms.
Among the SIH group, 11 of the participants (3.3%) reported previously having had bariatric surgery, compared with just two participants (0.8%) in the unruptured intracranial aneurysm group.
“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,” says study author Dr. Wouter I. Schievink.
“This could be the cause of sudden, severe headaches that can be treated effectively, but there can be serious consequences if misdiagnosed.”
The SIH symptoms in the bariatric surgery group began between 3 months and 20 years after their surgery, with participants having lost an average of 116 lb during that time.
Nine of the SIH patients who had undergone bariatric surgery responded to treatment, though two experienced persisting symptoms.
Dr. Schievink says that body weight can also influence CSF pressure:
“While more research is needed to understand the relationship between body weight and spinal pressure, it’s possible that the loss of fat tissue may uncover a susceptibility to spontaneous intracranial hypotension.”
In a spotlight feature last year, Medical News Today investigated whether the benefits of bariatric surgery outweigh the risks.