Symptoms and signs
The symptoms of familial Alzheimer’s disease are generally similar to those of sporadic Alzheimer’s disease, although other more unusual symptoms and neurological signs may occur.
Most people with familial Alzheimer’s disease have symptoms of memory loss from an early stage. In some individuals, memory impairment remains the only problem for many years. Changes in behaviour and personality may occur later in the disease and, more rarely, they can sometimes be the earliest features. The same is true of speech; in most individuals it is not affected until later in the disease but in some people, difficulty with speech and conversation may be an early symptom.
Many people with familial Alzheimer’s disease have no physical signs of the disease. Rarely, however, it can affect an individual’s walking by causing stiffness of the legs, unsteadiness, or slowing down of movements.
Involuntary jerking movements (called myoclonus) may develop; these may begin very subtly in the fingers and become more prominent in the limbs later in the disease course. Seizures can also occur, particularly in the later stages of the disease.
A progressive deterioration occurs in familial Alzheimer’s disease due to the ongoing loss of brain cells, causing people to need increased support in carrying out their daily activities. However, the rate of decline can vary considerably between individuals. In the later stages of the disease, full-time care may be required.