Lead Investigator: Prof Phillip Bath
Institution: University of Nottingham
Grant type: Project
Start Date: September 2010
Completion Date: March 2015
Scientific Title: Prevention of Decline in Cognition After Stroke Trial (PODCAST): a factorial randomised controlled trial of blood pressure and lipid lowering
What was the project, and what did the researchers do?
Many people can experience problems with memory and thinking after a stroke. Having this cognitive impairment after a stroke has been shown to be associated with an increase in risk of dementia and a poorer quality of life.
There is also evidence that having a stroke increases blood pressure and increases cholesterol levels in the blood. Because having raised blood pressure and cholesterol levels can increase risk of dementia, some researchers think this could explain why having a stroke affects dementia risk. Drugs that lower blood pressure and cholesterol levels have been found to reduce risk of further strokes. There is some evidence that the treatments may also have an effect on dementia risk.
In this project, the researchers aimed to find out whether these blood pressure and cholesterol lowering treatments had an effect on memory and thinking after a stroke. They gave people who had recently had a stroke either the current recommended blood pressure and cholesterol lowering treatments or a more intense dose of the same treatments. Assessing their memory and thinking may indicate their dementia risk.
What were the key results, and how will this help in the fight against dementia?
An important part of running a clinical trial is recruiting eligible participants. The more participants, the more reliable the study. This trial recruited a smaller than expected number of participants. The researchers thought this was due to a number of different issues, including the cost of the drug and changes to the organisations controlling NHS spending. When planning larger trials of blood pressure and cholesterol drugs, researchers will be able to use what they have learned about recruiting participants to ensure the study is large enough.
The researchers found no association between intense blood-pressure or cholesterol reducing treatments and cognition in this study. The intense dose of blood pressure drugs did lower blood pressure, and the intense dose of cholesterol drugs did reduce cholesterol levels. This result indicated that it is safe to give higher doses of these drugs and potentially effective, so further studies can take place.
What happened next? Future work and additional grants
This study provides some evidence that intense doses of blood pressure and cholesterol lowering drugs to reduce dementia risk could be worth investigating. Further studies will need many more participants, and the researchers now plan to assess feasibility of larger trials.
How were people told about the results? Conferences and publications
Baseline characteristics, analysis plan and report on feasibility for the Prevention Of Decline in Cognition After Stroke Trial (PODCAST), Scutt and Blackburn et al, Trials 2015, 16:509, doi:10.1186/s13063-015-1033-2