SCOTTSDALE, ARIZ. – The incidence of pseudotumor cerebri is rising among the obese, so physicians should keep this relatively uncommon condition in mind when obese patients present with symptoms resembling brain tumor or intracranial pressure, said Deborah Friedman, M.D., at the American Headache Society's 2004 Headache Symposium.
Pseudotumor cerebri is primarily seen in obese women of childbearing age, and although the condition affects only 1 in 100,000 people in the United States, the rate for obese women between the ages of 20 and 44 is about 19 per 100,000.
In areas with higher levels of obesity, however, pseudotumor cerebri is being seen more frequently.
In Mississippi, called the most overweight state in the nation because a quarter of its population is considered obese by BMI criteria, the incidence of pseudotumor cerebri in the overall population is double, at 2 per 100,000, and among obese women aged 20-44, the rate is about 25 per 100,000. Large increases in pseudotumor cerebri incidence rates have also been noted in men in the region, said Dr. Friedman of the University of Rochester (N.Y.).
The most common symptom, headache, occurs in about 90% of patients. Descriptions of the pain range from headache behind the eyes that feels like pressure to headache in the morning, said Dr. Friedman.
Visual symptoms, seen in about three-quarters of patients, are the second most common symptom, and papilledema is also very common.
“Patients will often describe blurriness or say that if they bend over, their vision goes out for a few seconds when they straighten up again,” Dr. Friedman said. “It's usually a sign that the optic nerve is swollen.”
About 60% of patients also experience the third most common symptom of intracranial noises, usually described as a whooshing in the ear or the sound of their heartbeat in the ear.
In diagnosing the disease, imaging and mental status are typically normal, and a lumbar puncture should show increased cranial pressure with otherwise normal spinal fluid content.
Dr. Friedman underscored the need for a lumbar puncture. “You have to do a spinal tap to make a diagnosis,” she stressed. “It's disheartening how many people I see who come in without having an LP.”
There are no evidence-based guidelines for treating pseudotumor cerebri, and not all patients even require treatment. But with the possibility of vision loss, the most important goal of treatment should be to preserve a patient's vision, she said.
An ophthalmologist needs to be brought in for such cases, but it's essential that the physicians collaborate on care, Dr. Friedman noted.
“Most of the time, there's no captain of the ship in management, and the doctors aren't working as a team,” she said. “It's crucial to have an ophthalmologist and a neurologist who are both following the patient and talking to each other about how to manage the patient.”