Diabetes drug may reduce Parkinson’s incidence

Diabetes patients taking rosiglitazone or pioglitazone had a 28% lower incidence of Parkinson's disease (PD) than people taking other treatments for diabetes who had never taken the glitazone (GTZ) drugs, according to a new study.

The study was published on July 21, 2015, in PLOS Medicine. 

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Researchers at the London School of Hygiene & Tropical Medicine in London conducted a retrospective cohort study in which individuals with diabetes who were newly prescribed GTZ drugs were matched by age, sex, practice, and diabetes treatment stage with up to five individuals prescribed other diabetes treatments. Patients were followed from 1999 until the first recording of a PD diagnosis, end of observation in the database, or end of the study (August, 2013).

They found that the rate of PD in the GTZ-exposed group was 6.4 per 10,000 patient years, compared with 8.8 per 10,000 patient years in those prescribed other antidiabetic treatments. “PPAR [peroxisome proliferation-activated receptor gamma] pathways may be a fruitful drug target in PD,” the researchers wrote.

"Our findings provide unique evidence that we hope will drive further investigation into potential drug treatments for Parkinson's disease,” Ian Douglas, senior author of the paper the London School of Hygiene & Tropical Medicine, told Science Daily. “It's thought that around one in 500 people are affected by Parkinson's, and to date no effective treatments have been found to directly tackle the neurodegenerative aspect of the disease."

In previous animal models, researchers found that drugs that bind to the PPAR (PPARγ agonist medications) may prevent nerve cell loss of PD.

Serious side effects

However, the researchers do not recommend that GTZ drugs, which have been associated with some serious side effects, be used as a treatment for PD. Rather, they suggest that the pathways in which PPARγ is involved might contain potential drug targets for PD and should be investigated.

The study only included patients with diabetes who did not have a PD diagnosis when they were first prescribed GTZ, so researchers could not establish whether GTZ use prevents or slows the progression of PD. In addition, the risk of PD was reduced among current users of GTZ drugs but not among past users.