Researchers from Rutgers Health found that penicillin antibiotics may reduce Parkinson's disease risk, while antifungals could raise it. This study adds to the growing evidence of the role gut bacteria play in brain health.

Rutgers Health researchers have unearthed a groundbreaking connection between antibiotics, antifungals and Parkinson's disease, revealing that penicillin antibiotics might lower the risk while antifungals could increase it.

The study, published in Parkinsonism & Related Disorders, analyzed over 93,000 medical records from the UK to arrive at these surprising conclusions.

Individuals who took five or more courses of penicillin antibiotics in the five years before their Parkinson's diagnosis showed approximately a 15% lower risk of developing the disease compared to those who had not taken antibiotics.

"We found an inverse dose-response relationship between the number of penicillin courses and Parkinson's disease risk across multiple durations," lead author Gian Pal, a neurologist at Rutgers Robert Wood Johnson Medical School, said in a news release. "This was unexpected and contrasts with some prior studies."

The study underscores the intricate connection between gut bacteria and brain health.

Parkinson's disease, a progressive disorder affecting movement and balance, has long puzzled scientists regarding its origins. Growing evidence now suggests that the trillions of microbes in our digestive tract might play a critical role.

"There's an idea that the disease starts in the gut and that inflammation in the gut can make the gut more leaky and allow toxins or inflammation to ascend to the brain through the vagus nerve," Pal added.

The research team delved into anonymized medical records from a significant UK database, comparing 12,557 Parkinson's patients with 80,804 individuals without the disease.

Notably, the study also discovered that people who took two or more courses of antifungal medications in the five years preceding diagnosis had about a 16% higher risk of developing Parkinson's. This finding aligns with past research from Finland.

Despite the intriguing results, Pal emphasized the modest nature of these associations.

"These are all very mild, so it should not influence decisions about when to use antibiotics or antifungals," he added. "The importance of the study is that it speaks to the idea that something is going on in the gut microbiome that could influence Parkinson's disease."

The study's limitations include its inability to consider other bacteria-affecting behaviors such as diet. Nonetheless, Pal advocates for further exploration into the relationship between gut microbes and Parkinson's risk.

"The fact that a medication that you take only for a few days to alter your microbiome in a small way alters your Parkinson's risk -- to me, that makes a stronger case that the microbiome is implicated," he added.

With more than 10 million people affected by Parkinson's globally, and cases expected to rise as the population ages, uncovering new prevention and treatment strategies is imperative. While the disease's exact causes remain elusive, it is believed to stem from a mix of genetic and environmental factors.

Future research endeavors will focus on identifying specific fungi or bacteria in the gut that may influence Parkinson's risk.

"Better understanding what the antifungal composition is in the gut - which really hasn't been well explored - and seeing if that is useful in distinguishing Parkinson's patients from non-Parkinson's patients would be useful," Pal said.

The researchers also aim to determine whether altering levels of certain gut microbes could either reduce the risk of Parkinson's or modify the course of the disease in those already diagnosed.

The study's findings, though preliminary, open new avenues of research that could reshape our understanding of Parkinson's disease and gut-brain connections.