Having PKD increases the risk of brain aneurysms. This is due to several factors, including the genetic aspects of PKD and its effect on blood pressure.

Polycystic kidney disease (PKD) is a hereditary disorder that causes multiple fluid-filled cysts to develop on the kidneys. The disease can lead to reduced kidney function and potential kidney failure.

According to the National Kidney Foundation, roughly 600,000 people in the United States are living with PKD.

In addition to affecting the function of the kidneys, PKD is also associated with other complications. One of these is an increased risk for aneurysms in the brain, which are estimated to occur in 8 to 12% of people with autosomal dominant PKD (the most common form of PKD).

This article takes a closer look at why PKD increases the risk of brain aneurysms, as well as symptoms to look for, and prevention strategies.

A brain aneurysm forms when the walls of an artery in the brain weaken, causing the affected area to balloon out. If a brain aneurysm ruptures (bursts), it can cause a brain bleed.

Compared to the general population, brain aneurysms happen 4 times more often in people with autosomal dominant PKD. Further, one 2019 study found that the rate of aneurysm rupture in those with autosomal dominant PKD is 5 times higher than that of the general population.

There are a few reasons for this increased risk. One of these is high blood pressure.

High blood pressure

Kidney disease, including PKD, can cause high blood pressure. In fact, high blood pressure is one of the most common signs that someone has PKD.

High blood pressure also increases the risk of brain aneurysms. This is because the increased pressure on artery walls over time can damage them and cause them to weaken.

Hereditary factors

Hereditary factors can also increase the risk of brain aneurysms.

Brain aneurysms are much more likely in people with PKD who have a family history of them. This is likely due to the genetics of PKD.

Autosomal dominant PKD, the more common type of PKD, is caused by mutations in the PKD1 or PKD2 genes. These genes code for polycystin proteins that are found in many different cell types, including those in the arteries.

The polycystin proteins encoded by PKD1 and PKD2 are important for maintaining the structure of the artery wall in response to stress.

Mutations in these genes can impair their ability to maintain artery walls, making them more susceptible to stress. This could contribute to the formation of brain aneurysms in people with PKD.

Many unruptured brain aneurysms don’t cause symptoms until they’ve grown to be big or until they rupture.

Large brain aneurysms can press on surrounding tissues, leading to symptoms like:

A ruptured brain aneurysm can cause the following symptoms to come on suddenly:

A ruptured brain aneurysm is a medical emergency

A ruptured brain aneurysm can lead to permanent brain damage or death. Call 911 immediately if you or someone you know is experiencing any of the symptoms above.

There’s no surefire way to prevent brain aneurysms if you have PKD. However, you can take steps to reduce your risk by addressing risk factors for brain aneurysms.

In addition to having a family history of brain aneurysms, other research involving participants with PKD has found the following risk factors for brain aneurysms:

  • being assigned female at birth
  • having a PKD1 gene mutation (as opposed to one in PKD2)
  • having high blood pressure, especially if it’s diagnosed at a younger age
  • having a current or previous history of smoking

While you can’t change some of these risk factors, you can certainly take steps to manage high blood pressure. In addition to using medications to lower your blood pressure, you can also:

So far, evidence is unclear on whether screening people with PKD for brain aneurysms will help to reduce rupture risk. However, the authors of a 2019 study suggest it may be beneficial for people with PKD who have a family history of brain aneurysms.

In addition to brain aneurysms, other complications associated with PKD include:

Women with PKD are also at risk for preeclampsia during pregnancy. Preeclampsia involves sudden high blood pressure after 20 weeks of pregnancy. The condition can cause complications for both mother and baby.

Several medications are specifically approved to treat PKD. In 2018, the Food and Drug Administration (FDA) approved tolvaptan (Jynarque) for people with autosomal dominant PKD.

Tolvaptan can help slow the progression of kidney disease in this group. However, it has the potential to cause other serious side effects, such as liver damage.

There are several other ways that PKD can be managed. These include:

About half of the people with PKD will have kidney failure by the age of 60. Kidney failure can be treated using dialysis or a kidney transplant.

The average life expectancy for people who have autosomal dominant PKD can vary. It typically ranges from 53 to 70 years.

A 2017 study using data from 1963 through 2014 noted that while the incidence of end stage renal disease has remained the same for people with PKD, survival in people receiving renal replacement therapy, such as hemodialysis and peritoneal dialysis, has improved over time.

Brain aneurysms are more common in people who have PKD.

The genetic mutations associated with PKD likely contribute to the increased risk of brain aneurysms. Additionally, PKD also leads to high blood pressure, a known risk factor for brain aneurysms.

While brain aneurysms cannot be prevented completely, there are steps you can take to reduce your risk.

Talk with your doctor about effective treatments for PKD and prevention strategies for brain aneurysms, such as managing risk factors like high blood pressure.