Idiopathic intracranial hypertension (IIH) is a perplexing condition that has eluded scientific understanding for years. It affects an estimated two out of every 100,000 people, and a rising number of cases are diagnosed every year. Yet its causes and effects remain shrouded in mystery, and the hunt for effective treatments continues. Fortunately, recent research is beginning to offer some clues that may help answer important questions about the disorder.
IIH occurs when cerebrospinal fluid (CSF) builds up in the brain and subjects sensitive brain tissue to abnormally high pressure. The condition causes symptoms similar to a brain tumor, including headaches, dizziness, nausea, and vision impairment. Vision problems can eventually lead to blindness in severe cases. Because of the overlap of symptoms between tumors and IIH, the condition is sometimes called pseudotumor cerebri–Latin for “false brain tumor.”
The Search for Causes
The cause (or causes) of IIH are still unknown. Some cases of intracranial hypertension are linked to obvious triggers, including some medications (acne medications, steroids, and others) and diseases (lupus, leukemia, meningitis, etc.). But as the word “idiopathic” in its name makes clear, IIH does not have an identifiable cause.
In searching for a cause, some scientists have focused on understanding who most often suffers from IIH. It is much more common in women than in men, particularly common in overweight young adult women.
A recent study has broken down the demographics of IIH risk even further. The study, published in the journal Neurology, found that risk was higher for Black and Hispanic women. Women with the condition were also more likely to live in low-income areas classified as “food swamps,” where food sources with low nutritional value (fast food restaurants, etc.) are plentiful, but high-quality food sources are scarce.
These results seem to confirm some long-standing suspicions about IIH–that lack of access to a healthy diet plays a role in the prevalence of the condition–but it may raise other questions. The study concluded, for example, that the elevated risk for Black and Hispanic women was higher than could be explained by socioeconomic differences. However, for the question of why that was so, the study’s authors had no answer.