Medical and recreational marijuana use may be legal in more than half of U.S states, but results from a recent study investigating cardiovascular outcomes found that it raises the risk of stroke and HF, even after accounting for demographic factors and additional lifestyle risk factors.

Study investigators found that use was not only associated with a 26 percent increase in the risk of stroke and 10 percent increase in developing HF, it also was linked to obesity, high blood pressure and smoking and alcohol use. Of the 20 million health records of young and middle–aged patients analyzed, marijuana use was diagnosed in 1.5 percent.

“More research will be needed to understand the pathophysiology behind this effect,” said Aditi Kalla, MD, the study’s lead author.

The study will be presented as abstracts during ACC.17.