According to a study presented at the American Heart Association’s Scientific Sessions 2015 and reported by American Heart Association News, high levels of exhaled carbon monoxide was associated with a greater risk of future stroke and transient ischemic attack among seemingly healthy adults.
Carbon monoxide is produced naturally by the human body as a signaling molecule. Because of carbon monoxide’s role in the body, abnormalities in its metabolism have been linked to a variety of diseases, including neurodegenerations, high blood pressure, heart failure, and inflammation.
Past studies have linked high exhaled CO levels to an elevated heart disease risk. In this study, researchers from the Framingham Heart Study analyzed the association between exhaled CO and stroke risk in 3,313 adults who were free of stroke at the study’s start.
CO exhalation levels were measured in all participants and brain imaging scans were available in 1,982 participants. They found that the participants were more likely to have lower total brain volumes, higher white matter volumes and a greater prevalence of silent stroke if they were in the highest third of CO levels, compared to those in the lowest third.
When they followed the patients for an average of almost 13 years, they found:
- Participants in the middle third of exhaled CO in the study population had a 67 percent increased stroke and TIA incidence compared to those in the lowest third.
- Participants with the highest third of CO exhalation had a 97 percent increased stroke and TIA incidence, compared to those in the third with the lowest CO exhalation levels.
Researchers said more research is needed to explore why this association between CO exhalation levels and stroke exists.