A feature of the development of dementia and one of its most dangerous forms – Alzheimer’s disease – beta-amyloid plaques, consisting of misfolded beta-amyloid proteins, are found not only in the brain tissues affected by the disease, but also in the olfactory centers.
All 515 participants were evaluated annually for 18 years of olfactory function and underwent cognitive testing and neurological studies. A subgroup of 121 participants underwent magnetic resonance imaging of the brain to monitor the reduction in gray matter volumes.
As a result, experts found that a rapid decline in the sense of smell in older people was associated with an increased risk of later cognitive impairment or dementia by 89% and 26%, respectively, as well as a reduction in gray matter volume.
These symptoms are early signs of Alzheimer’s disease. In addition, the scientists monitored the relationship between the increased risk of cognitive impairment against the background of olfactory loss and the risk of developing Alzheimer’s disease in carriers of the APOE-ε4 gene, which is involved in the development of neurodegeneration. It is stated that neuron death in persons with a loss of sense of smell is the same as that observed in patients with genetically determined Alzheimer’s disease.
Source: Ferra
