Genetically linked AD, or early-onset familial Alzheimer disease (FAD), is linked to three gene defects: amyloid precursor protein (APP) on chromosome 21, presenilin 1 (PSEN1) on chromosomes 14, and presenilin 2 (PSEN2) on chromosome 1 (McCance & Heuther, 2014). Mutations in APP, PSEN1, and PSEN2 lead to FAD by increasing the rate that the brain produces a peptide called beta amyloid (Kumar, Abbas, & Aster, 2013). The overproduction of beta amyloid leads to: neuritic plaques, neurofibrillary tangles, and neuronal and synaptic loss within the brain (McCance & Heuther, 2014).
The most common form of AD, sporadic AD, is associated with progressive loss of brain cells (McCance & Heuther, 2014). The cellular pathologic mechanisms for early-onset …show more content…
These changes include loss of purposeful muscle movement, muscle rigidity, and difficulty or complete loss of the ability to walk (McCance & Heuther, 2014). The digestive system may become affected as well. Weight loss can become significant as the person begins experiencing difficulties swallowing and changes in smell and taste. As the disease progresses loss of bowel and bladder control can occur. These manifestations will vary greatly depending on the severity of the disease, the age of onset, as well as the location of the abnormalities within the brain (McCance & Heuther, 2014).
Typical Age at Onset Most people with Alzheimer disease have the late-onset type, which typically affects people over the age of 65. The disease progresses over the course of two to 20 years, and individuals typically have a life expectancy of eight to 10 years after diagnosis (Alzheimer’s Foundation, 2016). Early-onset AD typically occurs in people ages 30 to 60, and represents only 5% of all Alzheimer cases (Alzheimer’s Association, 2016). Most cases of early-onset AD are related to mutations in the genes APP, PSEN1, and PSEN2.
Epidemiology
Risk …show more content…
Instead, symptoms will gradually present as short-term memory loss and then progress to a loss in cognitive and executive functioning. During the initial symptomatic stage of Alzheimer’s disease, it is common for the disease to be mistaken for forgetfulness as a part of aging, or another illness altogether. As Alzheimer’s progresses, the person will experience advanced memory loss and disorientation. The patient’s mood and behavior may also change. In advanced stages of Alzheimer’s disease, a patient may have a loss of speech and the inability to walk and eat. Many factors weigh into the extent of Alzheimer’s disease including age, the location of the brain affected, and cognitive symptoms (McCance & Huether,
The most common form of AD, sporadic AD, is associated with progressive loss of brain cells (McCance & Heuther, 2014). The cellular pathologic mechanisms for early-onset …show more content…
These changes include loss of purposeful muscle movement, muscle rigidity, and difficulty or complete loss of the ability to walk (McCance & Heuther, 2014). The digestive system may become affected as well. Weight loss can become significant as the person begins experiencing difficulties swallowing and changes in smell and taste. As the disease progresses loss of bowel and bladder control can occur. These manifestations will vary greatly depending on the severity of the disease, the age of onset, as well as the location of the abnormalities within the brain (McCance & Heuther, 2014).
Typical Age at Onset Most people with Alzheimer disease have the late-onset type, which typically affects people over the age of 65. The disease progresses over the course of two to 20 years, and individuals typically have a life expectancy of eight to 10 years after diagnosis (Alzheimer’s Foundation, 2016). Early-onset AD typically occurs in people ages 30 to 60, and represents only 5% of all Alzheimer cases (Alzheimer’s Association, 2016). Most cases of early-onset AD are related to mutations in the genes APP, PSEN1, and PSEN2.
Epidemiology
Risk …show more content…
Instead, symptoms will gradually present as short-term memory loss and then progress to a loss in cognitive and executive functioning. During the initial symptomatic stage of Alzheimer’s disease, it is common for the disease to be mistaken for forgetfulness as a part of aging, or another illness altogether. As Alzheimer’s progresses, the person will experience advanced memory loss and disorientation. The patient’s mood and behavior may also change. In advanced stages of Alzheimer’s disease, a patient may have a loss of speech and the inability to walk and eat. Many factors weigh into the extent of Alzheimer’s disease including age, the location of the brain affected, and cognitive symptoms (McCance & Huether,