Can Antibiotics Reduce Parkinson’s Risk?

Summary: Gut bacteria and fungi are linked to Parkinson's Disease

This study that evaluated more than 93,000 medical records found that those who had taken penicillin antibiotics had a lower risk of developing Parkinson’s disease in comparison to those who hadn't taken them. This implies a gut-brain link mediated by the gut microbes.

The link between microbes, fungi, antibiotics, antifungals and PD

A study conducted by researchers at Rutgers Health found a link between the use of antibiotics and the risk of developing Parkinson's disease (PD).

They found that individuals who had taken muliple courses of penicillin antibiotics had a modestly lower risk of developing the disease.

The authors suggest that the use of antibiotics impacts on the gut microbiota, which is somehow linked to the development of Parkinson's through a gut-brain connection.

The study involved analyzing the medical records of over 93,000 patients in the United Kingdom. Comparing 12,557 people who had been diagnosed with Parkinson's to 80,804 similar subjects without the disease.
Those who had taken 5 or more courses of penicillin antibiotics in the five years before diagnosis had a 15% lower risk of Parkinson's than those who had not taken antibiotics.

The Gut-Brain Pathway

The authors suggest that the microorganisms living in the digestive tract play a role in Parkinson's disease (PD), and this is caused by alterations in the balance of microbes in the gut, leading to inflammation, a more leaky gut and the flow of microbe-produced toxins into the brain.

... disruption of the intestinal microbiome (dysbiosis) might play a critical role in triggering the disease . In rats, aggregated alpha-synuclein has been shown to propagate from the intestinal wall, via the vagus nerve, to the brainstem . Studies have demonstrated an increased abundance of certain bacteria in those with PD, such as Akkermansia , and a reduction in other bacteria, such as Prevotella . Alteration of the gut microbiome may increase gut permeability , potentially resulting in translocation of endotoxins from the gut to the blood stream and eventually to the brain, where an inflammatory response may be triggered. Systemic and brain inflammation has been shown to exacerbate alpha-synuclein aggregation and neuronal loss... (1)

Antifungals impact on Parkinson's

The "mycobiome"

The study also found that "the risk of PD... was modestly modestly higher among those exposed to antifungal medicines in recent years." Those who had taken two or more courses of antifungal medicine in the five years before PD diagnosis had a 16% higher risk of developing the disease. This was in agreement with a previous study conducted in Finland. The authors suggest that antifungal medicine may also affect bacteria in the gut, and the possibility that the fungus species or "mycobiome" living in the gut may also play a role in Parkinson's. This will need to be investigated.

As in the prior study on antimicrobial medications and PD from Finland, we found an increased risk of PD among persons who recently received antifungal medications ... These data highlight the potential role of the mycobiome or «fungome» in PD. A case-control study comparing the fecal mycobiome and metabolite alterations in 35 adults with PD and 15 controls found a distinct pattern of fungal dysbiosis in those with PD. Interestingly, these authors found Torulaspora to be associated with an increased risk of PD. These findings were consistent with a prior study which identified Torulaspora delbrueckii in the oral mucosae of patients with early PD. However, an earlier study did not find a difference in abundance of fungi between cases with PD and controls. Given the long [incubation period] of PD... raise the possibility that the antifungal drug exposure may be a marker, rather than a trigger, of future disease. Lastly, it has been reported that non-antibiotic drugs can impact the gut microbiome composition. Anti-fungal drugs, such as imidazoles, may also have antibacterial activity, but this remains to be explored in future studies related to PD... (1)

References and Further Reading

(1) Gian Pal, Laura Bennett, Jason Roy, Abner Nyandege, M. Maral Mouradian, Tobias Gerhard and Daniel B. Horton, (2024). Effects of antimicrobial exposure on the risk of Parkinson's disease. 30 July 2024, Parkinsonism & Related Disorders. DOI: 10.1016/j.parkreldis.2024.107081