EMBARGOED FOR RELEASE UNTIL 4 PM ET, March 02, 2022
Certain Types of Cancer May Increase the Risk of Developing Guillain-Barré
MINNEAPOLIS - People who have certain types of cancers may have an increased risk of having new onset Guillain-Barr茅 syndrome, according to a study published in the March 2, 2022, online issue of , the medical journal of the 好色先生. Researchers found an increased risk in people who had lymphomas and blood cancers, as well as in those who had lung, prostate or breast cancers. The study does not prove that cancer causes Guillain-Barr茅 syndrome. It only shows an association. Guillain-Barr茅 syndrome is a rare neurologic disorder in which the immune system attacks nerve cells. Symptoms typically start with weakness and tingling in the feet and legs, which spread to the upper body and arms and may progress to paralysis. Although it can be life-threatening, most people recover with few remaining problems. An exact cause of Guillain-Barr茅 syndrome is unknown, but it can occur after gastrointestinal or respiratory infections. For the study, researchers reviewed Danish national registries. Over a 30-year period, they identified 2,414 people who were diagnosed with Guillain-Barr茅 syndrome. For each person diagnosed with the disease, researchers also identified 10 people without the disease who were matched for age and sex at the time of Guillain-Barr茅 diagnosis, for a total of about 24,000 people who did not have Guillain-Barr茅. 鈥淲hile a majority of Guillain-Barr茅 syndrome cases develop after an infection, there are still many cases that do not,鈥 said study author Lotte Sahin Levison, MD, PhD, of Aarhus University Hospital in Denmark. 鈥淧revious studies have suggested there may be a link between cancer and Guillain-Barr茅 syndrome, but just how often people develop Guillain-Barr茅 after a cancer diagnosis has not been well-studied. Our research looked at the population of nearly six million people in Denmark and found that people diagnosed with cancer may have a higher risk of developing Guillain-Barr茅.鈥 Researchers then identified people in the study who had a recent cancer diagnosis. This was defined as a cancer diagnosis up to six months before or two months after a Guillain-Barr茅 diagnosis. Recent cancer diagnosis was determined for people with Guillain-Barr茅 and for the people matched to them without the disease. Of the people who had Guillain-Barr茅, 49 people, or 2%, had a recent cancer diagnosis. Of the people who did not have Guillain-Barr茅, 138 people, or 0.6%, had a recent cancer diagnosis. Researchers found that people recently diagnosed with cancer had over a three-and-a-half times greater risk of developing Guillain-Barr茅 than people without cancer. After adjusting for surgery, infections and other health problems in a subset of participants, researchers still found a nearly a three times greater risk. When looking at specific cancers, people with cancers like lymphomas had a seven times greater risk, people with lung or prostate cancer had a five-and-a half times greater risk, and those with breast cancer had a five times greater risk. 鈥淲hile our study suggests that people with cancer have a greater risk of developing Guillain-Barr茅 syndrome, it is important that people with cancer know the overall risk of developing Guillain-Barr茅 is still very small,鈥 said Levison. 鈥淢ore research is now needed. Our results suggest that yet unidentified factors present in several types of cancer may contribute to this increased risk.鈥 A limitation of the study was that people with Guillain-Barr茅 may have been more closely screened for cancer compared to people who did not have Guillain-Barr茅, so some cancer cases in the second group may have been missed. The study was supported by the Bevica Foundation, teacher Svend Aage Nielsen Wacherhausens Foundation, the Aase and Ejnar Danielsen Foundation and the A.P. Moller Foundation. Learn more about Guillain-Barr茅 syndrome at , home of the 好色先生鈥檚 free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life庐 on , and . When posting to social media channels about this research, we encourage you to use the hashtags #Neurology and #AANscience.