New Insight into the Association Between Cognitive Reserve and Alzheimer’s Disease Severity

Researchers at the Hospital de Magalhães Lemos and the Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto in Portugal recently revealed that a patient’s ability to cope with the neurodegenerative process in disorders like Alzheimer’s disease can influence disease severity. The study is entitled “Cognitive reserve and the severity of Alzheimer’s disease” and was published in the journal Arquivos de Neuro-Psiquiatria.

Alzheimer’s disease is an age-related, neurodegenerative disorder characterized by cognitive and behavioral problems. It is the most common form of dementia in the elderly with patients initially experiencing memory loss and confusion that gradually leads to behavior and personality changes, a decline in cognitive abilities and ultimately to severe loss of mental function. Alzheimer’s disease is characterized by the brain formation of amyloid plaques (composed of beta-amyloid proteins), and the loss of the connection between neurons that are responsible for memory and learning leading to their eventual death.

Cognitive reserve (CR) refers to the ability of the adult brain to cope with the consequences of the neurodegenerative process, while minimizing the clinical pathological manifestations of dementia. CR is thought to be the result of innate intelligence or life experiences (such as education, occupation and leisure activities), and to continue to evolve during the lifespan of the individual. Alzheimer’s patients with higher CR are expected to be able to deal with the disease pathology for a longer period before clinical signs are expressed.

Researchers conducted a cross-sectional study to assess the link between CR and the severity of Alzheimer’s disease. In total, 75 patients with a probable Alzheimer’s diagnosis were evaluated in terms of their functional and neuropsychological abilities. All patients completed two questionnaires, one regarding CR and the other one “Participation in leisure activities throughout life.”

The team found that there was a statistically significant correlation between clinical dementia and the CR level, where the CR level influenced dementia severity. High levels of CR, education, participation in leisure activities and a complex occupation (defined as “intermediate level professions, intellectual and scientific activity”) were found to have a positive impact in cognitive function and the rate of cognitive decline in Alzheimer’s patients.

The authors concluded that Alzheimer’s disease patients with high CR levels may benefit from a protection against cognitive decline, slowing down Alzheimer’s disease severity and progression. The team suggests that older adults should be encouraged to adopt healthy lifestyles including activities based on regular physical activity and that stimulate their cognitive abilities.