Heart attack survivors tend to have a greater risk of other conditions, including stokes and vascular dementia. However, a recent study published in the Journal of the American Heart Association (AHA) showed that myocardial infarction (heart attack) survival was associated with a 20% decreased risk of developing Parkinson’s disease.
The researchers searched Danish medical registries from 1995 to 2016 and found almost 182,000 people who had a heart attack for the first time during that time period. They then found over 900,000 matched controls from the same registries. In their analysis, they controlled for known risk factors for both Parkinson’s and cardiovascular disease.
They found that one-year survivors of a heart attack had about a 20% lower risk of Parkinson’s disease. Additionally, they found that this population had a 28% lower risk of secondary parkinsonism, which is a group of disorders with symptoms similar to Parkinson’s disease that are usually caused by medications or other illnesses.
Parkinson’s disease is a nervous system disorder that causes tremors, stiffness, and other movement issues. In Parkinson’s disease patients, certain neurons in the brain break down or die. While the cause is not entirely understood, potential risk factors for Parkinson’s disease include genetics and exposure to certain toxins or environmental triggers.
Oddly, Parkinson’s disease is one of very few health conditions for which smoking decreases risk. Caffeine consumption also appears to lower risk. While the researchers who conducted the AHA study controlled for chronic pulmonary disease, it is possible that higher rates of smoking in heart attack survivors led to the decreased risk of Parkinson’s. Other risk factors for cardiovascular disease, including high cholesterol, have also been associated with lower Parkinson’s risk. While the researchers controlled for these factors, they may have also played a role.
Sources: Science Daily, JAMA, Mayo Clinic, BMJ