Researchers from the University of Helsinki focused on different kinds of oral antibiotics. Using nationwide medical data from Finland, they identified people who were diagnosed with Parkinson's disease from 1998 to 2014. They also obtained records of individual oral antibiotic purchases from 1993 to 2014.
The study authors then looked at data from 13,976 individuals diagnosed with Parkinson's disease and 40,697 Finns who were not. According to the researchers, those who took macrolides and lincosamides orally had the strongest risk for Parkinson's disease. Doctors often prescribe dosages of these two antibiotics to fight microbial infections. Further analysis also revealed that those who took broad-spectrum antibiotics had a higher risk for degenerative disorder.
The researchers also found that those who took anti-anaerobic medications and tetracyclines for 10 to 15 years had a higher chance of developing Parkinson's disease. On the other hand, they observed the same association in Finns who took sulfonamides, trimethoprim and antifungal medications for one to five years.
Considering changes in the gut microbiota in early and established Parkinson's disease, the researcher found that antibiotic use can affect gut microbial populations in the long run. Their findings align with previous research saying individuals diagnosed with Parkinson's disease usually have altered gut microbes.
"Exposure to certain types of oral antibiotics seems to be associated with an elevated risk of [Parkinson's disease]. The pattern of associations supports the hypothesis that effects on gut microbiota could link antibiotics to [the condition], but further studies are needed to confirm this," the authors concluded.
Parkinson's disease damages the part of the brain responsible for movement. The resulting damage causes hallmark symptoms such as stiffness, shaking and balance problems. Those with constipation, irritable bowel syndrome and inflammatory bowel disease have a higher chance of developing the degenerative disorder.
Previous studies have also found that changes in the gut microbiota typically found in those with Parkinson's disease can occur two decades before they are diagnosed with the disease. (Related: Chinese herbal formula found to protect against Parkinson’s disease.)
Neurologist and study co-author Dr. Filip Scheperjans says: "The link between antibiotic exposure and Parkinson's disease fits the current view that in a significant proportion of patients, the pathology of Parkinson's may originate in the gut. [This is] possibly related to microbial changes, years before the onset of typical … motor symptoms."
But prior to the study, no one had actually investigated whether or not antibiotic exposure had anything to do with Parkinson's disease. While the team's research found a link between the two, they noted that further investigations are needed to confirm it.
If later studies arrive at the same findings, doctors prescribing antibiotics against infections should take note of increased susceptibility to Parkinson's disease as a long-term risk. "The discovery may also have implications for antibiotic prescribing practices in the future," Scheperjans said.
"In addition to the problem of antibiotic resistance, antimicrobial prescribing should also take into account [the] potentially long-lasting effects on the gut microbiome and the development of certain diseases."
Brain.news has more articles about Parkinson's disease and factors that increase the risk of people developing it over time.