New research published in Neurology by Daniel Waldvogel, MD, and colleagues of the University of Zurich in Switzerland reports that nine people with Parkinson’s disease (PD), previously good swimmers, were unable to swim following deep brain stimulation (DBS). While movement symptoms improved following surgery, their ability to swim declined when the DBS device was turned on. (Read about DBS, the most common surgical procedure for PD symptoms.)

It’s important to note that this is early data. It’s not clear why or how DBS affects swimming, how many people lose their ability to swim after DBS or who might be most likely to experience this potential side effect. Further work is necessary to determine if and how the results of this small case study translate to the broad population of people who have or are considering DBS. (According to Medtronic’s website, 150,000 DBS devices had been implanted for Parkinson’s and other conditions as of 2017 — an important figure to compare to the nine in the study about swimming.)

Nonetheless, this is a noteworthy finding. Though the research is in the early stages, it holds potentially serious clinical implications. As research on DBS continues to develop, patients, families and doctors should be aware of the latest information on its risks and benefits.

If you have undergone or are thinking about DBS, talk to your doctor about what these findings may mean for you. They might lead you to consider a swimming test after DBS, or weigh your options differently when thinking about the procedure. Or, they may not play a major role in your decision-making.

The bottom line: Science and medicine are constantly evolving and new data is regularly emerging. While a case report suggests swimming ability could be affected following deep brain simulation for Parkinson’s, further research is necessary to know if and how this translates to the broad PD population.

Watch this space, as we will continue to update the Parkinson’s community if and as this research evolves.