Funded Studies
Objective/Rationale:
Several biological processes are thought to cause Parkinson’s disease. One involves inflammation within the central nervous system, but so far, no treatments are available for this aspect of the disease. Exciting results from laboratory experiments suggest a class of medicines called glitazones, which are already used to treat diabetes, may reduce or prevent the inflammation seen in Parkinson’s disease. It is now important to see if these drugs have a protective effect against Parkinson’s disease in humans.
Project Description:
Glitazones have been widely used by people with diabetes for more than 10 years. If they do have a beneficial effect in Parkinson’s disease we expect that some of the people who have been taking them regularly will have avoided developing signs of Parkinson’s disease as a beneficial “side effect” of the medication. The Clinical Practice Research Datalink is a rich source of data based on electronic health records for more than 11 million United Kingdom citizens and it contains high-quality information on the drugs people have been prescribed and the illnesses they have had. We will use these data to see if people taking glitazones are diagnosed with Parkinson’s disease less often than people taking other treatments for diabetes. We will also see if any effect of glitazones changes over long periods of treatment.
Relevance to Diagnosis/Treatment of Parkinson’s Disease:
The results of this study will help us see if glitazones may be a useful treatment for Parkinson’s disease and also help us focus on how best to study their use as a treatment in the future. Current treatments have not been able to tackle the inflammatory component of Parkinson’s disease and so any progress in this area would represent an important step forward.
Anticipated Outcome:
Our preliminary work shows we will have enough data to potentially detect a 25 percent reduction in Parkinsons’s disease amongst glitazones users, compared with users of other diabetes treatments. If we do find a protective effect around this size, it would represent a clinically meaningful effect for people with Parkinson’s disease and would signal further exploration of glitazones as a potential treatment for Parkinson’s disease is warranted through randomized trials.
Final Outcome
In this study, we aimed to test the ability of diabetes drugs glitazones to treat Parkinson's disease (PD). In the Clinical Practice Research Datalink (a database of health records), we identified over 44 thousand people with diabetes treated with a glitazone drug and over 120 thousand people with diabetes treated with a drug other than glitazone. We found that people taking glitazones were less likely to develop Parkinson's over the course of 5 to 6 years than those receiving other treatments. For every four people diagnosed with Parkinson's disease in the group receiving non-glitazone treatments, only three were diagnosed with PD in the group treated with glitazones. The protection from PD was strongest during glitazone treatment, with little evidence of protection after the treatment. Two glitazone drugs, rosiglitazone and pioglitazone, had a similarly protective effect. Unfortunately, there were not enough participants in our study to determine whether people with Parkinson's disease had better clinical outcomes if they received a glitazone, but our results indicate that the mechanism of action of glitazones may suggest new therapeutic targets for Parkinson's disease.
October 2014