As populations age, Alzheimer’s and dementia are becoming more prevalent. A new drug could offer hope

It is one of the biggest diseases of our time: 10 million new cases of dementia are diagnosed every year, according to the World Health Organization (WHO). More than 55 million people worldwide live with a form of dementia and it is the seventh leading cause of death among all diseases.

Now a new drug is offering a glimmer of hope after years of searching for a treatment. In clinical trials, lecanemab has been shown to slow the cognitive decline associated with the disease. The drug attacks the protein clumps in the brain that many think are the cause of the disease.

Although dementia patients are currently offered drugs, none of them affect the progression of the disease which is why scientists in the field are so excited about this latest development. Alzheimer's Research UK called the findings "a major step forwards".

But while this is undoubtedly positive news, the body also points out that the benefits of the drug were small and came with significant side effects. In addition, lecanemab has been proven to work in the early stages of the disease, so would rely on doctors spotting it before it had progressed too far.

With the number of dementia cases expected to rise to 78 million by 2030 and 139 million in 2050, according to the WHO, the race is on for scientific developments and research that will help us understand, treat and possibly prevent the disease.

As populations age, the number of cases of dementia rises. While the deterioration of cognitive functioning is not caused by age itself, it does primarily affect the older generation. For many elderly people it also results in disability and loss of independence - which can have psychological, social and economic implications for them and their families, carers and society more broadly.

The estimated global cost of dementia to society was placed at $1.3 trillion in 2019, and is expected to rise to $2.8 trillion by 2030, WHO says.

Dementia is a collective term for a group of diseases or injuries which primarily or secondarily affect the brain. Alzheimer’s is the most common of these and accounts for around 60-70% of cases. Other types include vascular dementia, dementia with Lewy bodies (abnormal protein clumps) and a group of diseases that contribute to frontotemporal dementia.
It can also be triggered by strokes, excessive use of alcohol, repetitive head injuries, nutritional deficiencies, or follow some infections like HIV, the Alzheimer’s Society explains.

The different forms of dementia can often be indistinct and can co-exist.

Different people are affected in different ways, depending on the underlying cause. But the syndrome is usually progressive and can affect a range of functions, including memory, thinking, orientation, comprehension, calculation, learning capacity, language and judgement.

Changes in mood and ability to control emotions often accompany these cognitive variations.

There is no cure for dementia, although there are numerous treatments being worked on and at clinical trial phase. Dementia care currently focuses on early diagnosis, optimizing health and wellbeing and providing long-term support to carers.

Besides age, there are a number of other risk factors, which if avoided, can decrease the chances of dementia and slow its progression. Preventative steps include being physically active, not smoking, avoiding the harmful use of alcohol, as well as maintaining a healthy diet, weight, blood pressure, cholesterol and blood sugar levels.

Other risk factors associated with dementia include depression, social isolation, low educational attainment, cognitive inactivity and even air pollution.

People with dementia rely heavily on informal care - i.e., friends and family. These carers spent on average five hours a day looking after people living with dementia in 2019, according to WHO figures. Informal care is thought to cover half of the overall financial burden of dementia.

There is also a disproportionate impact on women. They account for 65% of all dementia-related deaths, and also have a greater number of years affected by the disease. Women also typically provide the majority of informal care - covering over two-thirds of the carer hours for people living with dementia.

The fact that dementia is only diagnosed once symptoms appear means that by the time people take part in clinical trials the disease is often quite well advanced. This can hamper the development of drugs. However, research analyzing data from the UK Biobank has indicated there are a collection of signals that could indicate a problem years before dementia is currently being diagnosed.

Other scientists postulate that, rather than being a disease of the brain, Alzheimer’s is in fact a disorder of the immune system within the brain. They believe research should instead focus on drugs targeting auto-immune pathways.

On a less positive note, researchers found that people who have recently received a dementia diagnosis, or diagnosed with the condition at a younger age, are at an increased risk of suicide. This underlines the importance of a strong support network, particularly among those newly diagnosed.