Alzheimer's disease typically starts slowly and the symptoms can be very subtle in the early stages. As the disease progresses, symptoms become more noticeable and interfere with daily life. The disease affects each person differently and the symptoms vary.
Common symptoms include:
- persistent and frequent memory loss, especially of recent events
- vagueness in everyday conversation
- being less able to plan, problem-solve, organise and think logically
- language difficulties such as finding the right word and understanding conversations
- apparent loss of enthusiasm for previously enjoyed activities
- taking longer to do routine tasks
- becoming disoriented, even in well-known places
- inability to process questions and instructions
- deterioration of social skills
- emotional unpredictability
- changes in behaviour, personality and mood.
Symptoms vary as the disease progresses and different areas of the brain are affected. A person's abilities may fluctuate from day to day, or even within the one day, and can become worse in times of stress, fatigue or ill health.
The stages of Alzheimer's disease progress from mild Alzheimer's disease (which can be so subtle that it might only be recognised in hindsight) to moderate Alzheimer's disease and then severe Alzheimer's disease. During severe Alzheimer's disease, people need continuous care. The rate of progression between these stages differs between people.