clare walton - exercise and health conference
TRANSCRIPT
Reducing dementia risk with exercise
Dr Clare WaltonResearch Manager
Reducing dementia risk through exercise
Dr Clare WaltonResearch Manager
Dementia risk factors% with dementia• Age – the biggest risk factor for dementia
• Genetics
• Environment
Dementia risk factors• Age – the biggest risk factor for dementia
• Genetics
• Environment
modifiable factors
Caerphilly cohort study
• 1979 heart disease study with 2,235 men in Wales• Lifestyle, physical and cognitive health tracked for 30+ years
Those who followed 4 or 5 healthy behaviours:1. Taking regular exercise2. Not smoking3. Healthy weight (BMI 18-25)4. High fruit and veg intake (>3 pieces a day)5. Low-moderate alcohol intake (<3 units a day)
60% reduction in
dementia
Exercise & dementia• More than 50 observational studies looking at physical
activity and cognitive impairment or dementia
• A 2014 review of 28 studies - 25 showed high vs low physical activity was linked to lower rates of dementia.
High physical activity definitions:
• Between 2 and 4 aerobic activities per week
• More than 2 miles walking per day
Combining the studies
Beydoun et al (2014) BMC Public Health, 14: 643
How does it work?
Hippocampal volume Glucose metabolism Beta-amyloid burden
But both groups showed significant memory improvements over the year – no difference!
Erickson et al (2011). PNAS, vol. 108: 3017–3022
120 people (average age 65 years) randomly assigned to 3 days/week of either aerobic exercise or stretching for 1 year
How does it work?
Intervention studies• No intervention studies to directly test the effect of physical
activity on dementia• Studies looking at effect of physical activity on cognition in
older people have produced mixed results
E.g. LIFE study in USA• RCT with 1,600 sedentary adults (70-89 yrs)
• Exercise 5-6 times a week VS weekly health education class
• No difference in cognition or incidence of dementia between groups after 2 yrs
Intervention studies• Meta-analysis of exercise interventions in people with Mild
Cognitive Impairment (Wang et al. J Alzheimers Dis. 2014)
> A small but significant improvement in global cognitive function in exercise groups – clinical significance?
FINGER study in Finland• RCT with 1,260 at-risk adults (60-77 yrs)
• Multi-domain intervention (diet, exercise, cognitive training, blood pressure control)
• Improvements in cognition after 2 years compared to control group
- 2011- 1991
• Dementia rates declining
• Improvements in CVD disease management and prevention (i.e. smoking)
• 1 in 3 cases of dementia could be preventable
Public awareness is poor• Survey of 5400 people in July 2015• Qu: Which of the following do you think regular exercise and physical
activity can have a significant impact on for many people?
Only 36% thought exercise could
reduce dementia risk
Public awareness is poor• 1711 people surveyed were 55 years or older• Qu: Approximately, how many minutes of moderate exercise do you
do during an average week?
Less than 20% reach the recommended amount of activity
In summary• Strong evidence that physical activity is associated with
lower rates of dementia and cognitive decline
• Not enough existing evidence to show exercise interventions can reduce cognitive decline or dementia
• What intensity and duration of exercise is suitable and effective for maintaining cognitive health in older people?
• Public awareness is poor – public health campaigns are needed
Find out more
Lifestyle risk factors:alzheimers.org.uk/ReduceMyRisk
Research funding:alzheimers.org.uk/ForResearchers