Study: Rare Disorder That Causes Headaches Is on the Rise, Especially in Women

Woman holding head by computer screen with a headache.

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Key Takeaways

  • Idiopathic intracranial hypertension (IIH) is considered a rare disorder; however, a new study shows that cases are rising.
  • IIH cases are increasing alongside rising obesity rates.
  • Women are most often affected by IIH, which can cause headaches and vision problems.

When is a headache more than a headache? For patients diagnosed with idiopathic intracranial hypertension (IIH), what starts as a debilitating headache can lead to other symptoms, like vision loss.

According to a new study published on January 20 in the journal Neurology, IIH cases are on the rise.

What Is IIH?

Idiopathic intracranial hypertension (IIH) occurs when there is pressure in the skull caused by an increased volume of spinal fluid. The increased pressure causes a sudden but intense headache, as well as a loss or inhibition of vision. IIH is often initially diagnosed as a brain tumor and is more common in women than men.

The Study

Researchers in Wales analyzed data from 2003-2017 which showed a significant increase in IIH cases. The results also showed that there were common factors in IHI cases, including weight, sex, and socioeconomic circumstances.

The study's lead researcher, William Owen Pickrell, PhD, MRCP, a consultant neurologist and honorary clinical associate professor at Swansea University in Wales, tells Verywell that IHI is often found by eye doctors who are investigating a loss of vision and find swelling of the optic discs.

"What we refer to as your optic nerves are really an extension of your brain, and not really a separate nerve," Pickrell says. "It's a part of your brain that's surrounded by a thin layer of spinal fluid. When the pressure increases, the fluid around the optic center increases, which is quite sensitive."

Left unchecked, IIH can lead to severe vision loss, as well as continuing headache pain.

Treatment for severe cases can include brain surgery to relieve the pressure from the excess fluid through a cranial shunt. Non-surgical treatments include medication and weight loss.

What This Means For You

Idiopathic intracranial hypertension is more than just a headache. Women, especially those who overweight and/or are socioeconomically disadvantaged, are more likely to develop IHI. If you are experiencing severe headache pain and vision loss, reach out to your doctor for treatment.

IIH and Obesity Rates Both Rising

The researchers found that the incidence of IIH has increased six-fold over the course of the 15-year study. During that time, obesity rates have also been rising.

Pickrell says that the rates of IIH diagnosis have risen proportionately to the rates of obesity. "The main treatment is weight loss, although that is very, very difficult," Pickrell says. Gastric bypass or band surgery is rare in Wales, which means that most patients have to approach weight loss with diet and exercise.

There is currently a clinical trial being conducted by the University of Birmingham to investigate whether bariatric surgery or structured weight loss programs could be effective methods of reducing IIH.

Both men and women can be afflicted by IIH, although it is far more prevalent in women—especially those of childbearing age.

Pickrell says that researchers are still studying why women are more likely to develop IIH. Regardless of whether they were male or female, weight was a consistent factor among those diagnosed with the condition.

The Role of Socioeconomic Circumstances

Pickrell also found that deprivation levels seemed to play a part in IHI—especially for women. The study indicated that women with fewer socioeconomic advantages were at a particularly increased risk for IHI.

What Is Deprivation?

Deprivation refers to several factors, including income stability, access to healthcare, education, safe housing, and community safety, among others.

Using the Welsh Index of Multiple Deprivation (WIMD), Pickrell and his colleagues found that women with higher deprivation rates were more likely to have IIH.

"So many diseases and health outcomes are linked to deprivation, really," Pickrell says. "Chronic diseases are more common, and the outcomes are worse. Nutrition is certainly a factor. Obesity is more common in more deprived areas. It could be environmental pollution or smoking rates."

However, Pickrell says that he cannot make any firm conclusions about why deprivation is linked to IHI. Within the parameters of the study, deprivation was geographically based on where patients lived rather than on the patients' individual deprivation level.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cedars-Sinai. Idiopathic intracranial hypertension.

  2. Miah L, Strafford H, Fonferko-Shadrach B, Hollinghurst J, Sawhney IM, Hadjikoutis S, et al. Incidence, prevalence and healthcare outcomes in idiopathic intracranial hypertension: a population study [published online ahead of print, 2021 Jan 20]. Neurology. 2021. doi:10.1212/WNL.0000000000011463

  3. University of Birmingham. IIH: WTT trial.

By Rachel Murphy
Rachel Murphy is a Kansas City, MO, journalist with more than 10 years of experience.