not a normal part of aging
As we age, most people experience some memory problems and a reduction of cognitive speed, and this is normal. Dementia and cognitive impairment, however, are caused by pathological processes that damage the brain cells and gradually deteriorate a person’s cognitive capabilities.
Symptoms include memory loss, problem-solving difficulty, and inability to plan and carry out day-to-day tasks. Language and communication, perception of time, and the ability to orientate oneself are affected. Anxiety, depression, and behavioral changes are common.
Causes
The most common type of dementia, Alzheimer’s disease, is associated with excessive production of a body-specific protein, beta-amyloid, which starts accumulating in the brain and causes damage to the brain’s nerve cells. In this process, while the beta-amyloid forms plaque around the neurons, another protein, tau, starts forming tangles inside the nerve cells and harms their function. Around these changes, inflammation and oxidative stress occurs, with negative effects on the brain cells.
Also in Lewy body dementia and frontotemporal dementia, the damage is associated with abnormal deposits of specific proteins. In vascular dementia, the brain damage is related to cerebrovascular or cardiovascular disorders. Especially among elderly persons, it is common to have so-called mixed dementia. This means that the dementia is caused by different changes in the brain, for instance both Alzheimer’s disease and vascular dementia.
Genetic factors play a role, and carriers of the gene ApoE4 are particularly susceptible of developing Alzheimer’s disease. However, a person may have ApoE4 and never develop dementia. In the FINGER study, our research teams saw that ApoE4 carriers benefitted clearly from the multimodal lifestyle interventions of the trial.
Our cognitive reserve
Our brains are moldable and modifiable. In modern neuroscience, we talk about the brain’s plasticity. At all ages, through cognitive, physical, and social activities, we can build up a cognitive reserve and rich networks within the brain. If a person’s brain is damaged, a large cognitive reserve can help compensate for the impairment and delay the onset of symptoms. Our lifestyles and everything we do affect the brain’s function, structure, and ability to adapt and repair itself.
Prevention
and treatment
Lifestyle interventions
Recent research shows that up to 40% of all cases of cognitive decline can be prevented or clearly delayed with simultaneous multimodal lifestyle interventions. Several trials are completed, ongoing, and planned to develop the evidence even further and try out the FINGER model in different settings, contexts, and combinations.
Medication
Symptomatic treatments are available, and new disease-modifying drugs are being developed, which target amyloid and can slow the development of Alzheimer’s disease in some patient segments.
We expect that in the coming years, precision preventive measures and drug treatments will cooperate at different stages in the battle against dementia. In FINGER research, we are currently studying the effects of combining lifestyle interventions and various pharmacological interventions on the prevention of cognitive impairment.
Increasing
in absolute numbers
The risk of developing dementia today is lower than ever in the developed world. Out of 1,000 persons, fewer individuals get dementia in relative numbers. This may be due to a higher level of education, better management of various risk factors, and a healthier lifestyle. However, since a larger portion of populations are reaching old age, there are more cases of dementia in absolute numbers.
Some risk factors may be increasing, such as stress, sleep problems, diabetes, and hearing loss.
In some parts of the world, dementia actually seems to be increasing also in relative terms. This may be attributable to risk factors like increased smoking and obesity.
It is important that we continue to monitor these trends and understand their effects.