Welcome to Study of the Week from Patient Worthy. In this segment, we select a study we posted about from the previous week that we think is of particular interest or importance and go more in-depth. In this story we will talk about the details of the study and explain why it’s important, who will be impacted, and more.
If you read our short form research stories and find yourself wanting to learn more, you’ve come to the right place.
This week’s study is…
Incidence, prevalence, and healthcare outcomes in idiopathic intracranial hypertension: A population study
We previously published about this research in a story titled “Doctors Study Why This Brain Pressure Disorder Increase Six-Fold,” which can be found here. The study was originally published in the American Academy of Neurology’s medical journal Neurology. You can view the fully study text here.
What Happened?
This research was a population study that aimed to evaluate incidence and prevalence of idiopathic (without known cause) intracranial hypertension (IIH) over time. The study used patient data from the Wales region in the UK and analyzed data collected between 2003 and 2017. This data was drawn from the Secure Anonymised Information Linkage databank. The researcher used primary and secondary care diagnosis codes for IIH and also recorded evaluated other patient characteristics such as unscheduled hospital admissions, body mass index (BMI), CSF diversion surgery, and deprivation quintile.
In 2003, prevalence of the disease was 12/100,000 with incidence of 2.3 per 100,000. These figures increased by 2017 to 76/100,000 and 7.8/100,000 per year, respectively. This was a significant, six-fold increase in cases for the Wales region. A total of 1,765 people living with the disease were identified, with 85 percent of patients being women. A dominant risk factor for idiopathic intracranial hypertension is obesity, and the researchers found that the increase in cases was likely due to an increase in obesity rates over the time period. 29 percent of the population in Wales was obese in 2003; by 2017, this percentage had increased t0 40 percent.
A high body mass index was also found to be associated with the appearance of the condition. For women, socioeconomic factors also played a role; these factors included income, education, and housing. Women with less socioeconomic resources were found to be at greater risk. Though the researchers thought that this may have been the result of increased obesity among this group, the findings suggest that low socioeconomic status increased risk whether obesity was present or not.
One limitation of the research was that women were sorted into a given socioeconomic bracket based on where they lived, as opposed to the more in-depth approach of obtaining socioeconomic status for each patient.
About Intracranial Hypertension
Intracranial hypertension is a condition of increased pressure within the skull. Normally there is a typical range of pressure (called intracranial pressure) that is maintained around the brain. However, when this pressure increases abnormally, serious problems can occur. In some cases, this condition appears without apparent cause and most frequently impacts women from age 20-50. Risk factors include tetracycline use, being overweight, or recent weight gain. The condition can also appear from a secondary cause, such as certain drugs or systemic diseases. Symptoms include severe headaches, tinnitus that pulses with the heartbeat, neck and shoulder pain, vomiting or nausea, numbness, papilledema, vision changes, coordination problems, weakness, and inability to smell. Treatments for intracranial hypertension include lumbar puncture, certain surgical procedures, venous sinus stinting, and certain medications such as acetazolamide. Outcomes vary, with some seeing remission and other having long term symptoms. To learn more about intracranial hypertension, click here.
Why Does it Matter?
The results of this study clearly demonstrate the rates of idiopathic intracranial hypertension are increasing with obesity rates. Clearly obesity is not only increasing in Wales and is a growing problem, particularly in the developed world. In fact, rates of obesity tripled between the years 1975 and 2016. With this in mind, it’s certainly possible that rates of this disease are also increasing in other regions where obesity is becoming more common.
The connection between this disease, obesity, and the potentially debilitating complications that it can cause has major implications for the health systems and policy in Wales and other regions where rates are likely increasing. The increase in disease prevalence also places an increased urgency on the need for more effective treatment approaches. While there are multiple procedures, lifestyle changes, and medications that can help resolve the symptoms of idiopathic intracranial hypertension, the fact remains that there are still a significant portion of patients that develop chronic symptoms that don’t resolve with current treatments.
The findings related to socioeconomic factors independent of obesity also represent a path of much needed continuing research that may reveal other potential triggers of the condition. At this juncture, it is unclear if factors associated with low economic status, such as pollution exposure, differences in diet, stress, or smoking can be linked to the appearance of the disease. Only with further research into risks and treatments can outcomes improve for patients living with idiopathic intracranial hypertension.
