Dementia refers to a significant, long-term decline in memory, thinking, and problem-solving, which affects a person's ability to perform daily tasks. It results from various conditions that cause damage to specific brain regions over time. One of the most common causes of dementia is Alzheimer’s disease, where the build-up of certain proteins occurs gradually over many years.  To help prevent dementia, treatments may need to be given early, before memory and thinking problems become apparent.

Statins are one of the most common treatments used to lower cholesterol levels, and are given to people who are at an increased risk of a heart attack or stroke. Some evidence suggests that statins might also be beneficial to help prevent dementia, and we have a large trial underway to test this hypothesis. However, in order to fully assess the effect of statins, we need to determine whether statins can stop the accumulation of Alzheimer’s disease proteins in the brain. We also need to see whether sensitive markers of brain changes which precede the onset of dementia symptoms, can be altered with statin treatment.  

Our large clinical trial involves individuals aged 70 and over, with regular assessments of thinking and memory. At the start of the study we performed sophisticated scanning of some of the participant’s brains and also collected a blood sample. Half of the individuals were then given statins to take daily for an average 5-year period, and the other half a placebo tablet (inactive ‘sugar’ pill). We now have the unique opportunity to repeat the brain scanning and collect an additional blood sample. We can then directly determine what effect statins have had on changes in the brain and blood measures of Alzheimer’s Disease proteins. Through this, we can provide solid evidence about whether statins can be used to prevent dementia.