The number of people living with dementia worldwide in 2019 was 57 million. That number is expected to rise to 153 million by 2050. A recent article in the Lancet (Dementia Prevention Intervention, and Care report of the Lancet Standing Commission (Volume 404, Issue 10452, P572-628, Aug. 10, 2024) is an incredibly detailed review of risk factors and the effectiveness of preventing dementia. This is a summary of this report.

Two new factors have been identified — untreated vision loss and high LDL making that 14 factors to consider. The potential for preventing dementia by eliminating these risk factors is an amazing 50 per cent.

• These are life-long risks and should be paid attention to as early as age 18 by encouraging exercise and being socially active. Paying attention to these lifestyle choices should be a goal.

• Risk is modifiable irrespective of your ApoE stratus (genetic predisposition). The evidence that treating hearing loss decreases the risk of dementia is stronger than first identified.

• Reducing air pollution is linked to improved cognition and less dementia. I often wonder what price we will pay for having to endure all the smoke from fires that is a yearly occurrence. Proper prevention and treatment of traumatic brain injury is necessary.

The article recommends specific actions for these risk factors.

1. Ensure good quality education is available for all and encourage cognitively stimulating activities in midlife to protect cognition.

2. Make hearing aids accessible for people with hearing loss and decrease harmful noise exposure to reduce hearing loss.

3. Treat depression effectively.

4. Encourage use of helmets and head protection in contact sports and on bicycles.

5. Encourage sport and exercise.

6. Reduce cigarette smoking through education, price control, preventing smoking in public places and make smoking cessation advice readily accessible.

7. Prevent or reduce blood hypertension and maintain systolic BP of 130 mmhg or less from age 40.

8. Detect and treat high LDL cholesterol from midlife.

9. Maintain a healthy weight and treat obesity as early as possible, which also helps prevent diabetes.

10. Reduce high alcohol consumption through price control and increased awareness of levels and risks of over consumption.

11. Prioritize age-friendly and supportive community environments and housing. Reduce social isolation by facilitating participation in activities and living with others.

12. Make screening and treatment for vision loss accessible for all.

13. Reduce exposure to air pollution.

14. Neuropsychiatric symptoms should be treated. Care coordinated multi-component interventions are helpful.

• Rates in women are higher than men in most countries but women live longer and have lower education rates, world wide, this may lead to higher levels of poverty. As education increases, the difference is reduced.

• Hearing loss was significant — for each 10db loss, there is 4-24 per cent increase in dementia. Causation is difficult to determine since those with hearing loss also lose some socializing and may experience depression and social isolation, all of these contribute to dementia. Also complicating this is vascular disease could cause both hearing loss and dementia. Hearing aids do help to reduce this risk.

• Exercise at any age is helpful, with increased blood flow, reduced hypertension, increased Nitrous oxide (dilates arteries) leading to enhanced brain plasticity and reduced inflammation in the brain.

• There is evidence that age-specific dementia incidence rates have decreased with time, showing some prevention is possible, especially in socially advantaged areas. However the rising rate of Type 2 diabetes, alcoholism can push theses rates up.

• Overall, people living healthier lives can expect to live longer than people with unhealthy lifestyles, and if they develop dementia, live fewer years with the disease, with notable quality of life implications for individuals.

• Cognitive Reserve: Most people with dementia have more than one neuropathology. The ability to withstand neuropathology before showing signs of dementia is described as cognitive reserve. Healthier people have more cognitive reserve. Physical, cognitive and social activities increase your cognitive reserve. Less vascular disease also increases the reserve.

• Diabetes as a risk factor is less important if it develops later in life, smoking is a risk factor any time.

TREATMENT

• Computerized Cognitive training interventions to maintain cognitive function showed low-quality evidence of short-term effect that wasnot present in long term.

• Cholinesterase inhibitors and memantine are useful for both Alzheimer’s and Lewy Body Dementia.

• Anti-amyloid B antibodies are a new approach but are limited by cost and significant side effects.

• Forgetfulness must be considered when taking medications and safeguards to assure directions are followed should be in place.

• Be aware that being admitted to hospital for an acute condition, they may deteriorate quickly and need extra care.

Once diagnosed with dementia, it is important to continue with the above, and provide support to caregivers and manage neuropsychiatric symptoms. Newer exciting results from Dr. Tsai at MIT have shown significant improvement using a light and sound system that creates gamma waves, used for an hour a day. This has minimal side effects and could be a significant treatment for the future. Studies are ongoing

Dr. Vicki Holmes is a Saskatoon retired family physician who has a special interest in Palliative Care and Women’s Health. She is passionate about sharing medical information with the public! (Vicki’s Photo: Memories by Mandy)

– Dr Vicki Holmes