How does the disease progress?
It is assumed that a person will live for approximately seven to ten years after being diagnosed with Alzheimer disease. The disease progresses slowly but inexorably. The patient first forgets the events that happened most recently, and then memories of the past. In terms of what he remembers he goes further and further back into the reality of his childhood. Physically and mentally the patients may regress to the functional stage of an infant: Barely able to hold the head, no language, not able to eat or drink and unable to control bladder and bowel.
Today the diagnostic process has been refined and Alzheimer disease may be diagnosed even if the patient has only subtle symptoms or no symptoms at all. Symptomatic dementia is divided into three stages:
In this stage the symptoms are still subtle and often hardly recognized by persons less close to the patient. This phase is characterized by disturbances of concentration, the feeling that everything is too much, rapid mental exhaustion, lack of drive, lack of interest, vague fears, social withdrawal. It is predominantly the ability to convert new information to memory that is affected – that is, the ability to learn. In this stage the patient may still be able to cope with everyday life relatively independently, however sticky notes, alarms and shopping lists may help compensate for the failing memory.
In this stage the symptoms become more marked. Noticeable disturbances of memory and orientation develop. Patients get lost in their accustomed environment. They increasingly develop personality changes and may be irritable or aggressive. The ability to make judgments is restricted. Complex practical instructions can no longer be followed. The patient is no longer able to disguise the loss of his faculties. It is at this stage that the majority of dementia disorders are identified and diagnosed. Household, food intake and personal hygiene are increasingly neglected. The patient enters a phase where help from relatives or carers in carrying out daily tasks is needed. Behavioral features such as aggressiveness and restlessness become evident.
In this stage the patient is completely dependent on help from other people. He no longer recognizes the place where he lives as his home, relatives have become strangers. His ability to relate to the present, together with old memories, is increasingly being lost. Eating and drinking are unlikely to be possible without help from someone else, difficulties in swallowing may develop. In this stage – but mostly even before this – the patient loses control over his bladder and bowels and needs to wear incontinence aids (diapers). The patient may become bed-ridden and totally dependent on care. Not all patients go through the 3 stages as described and not every patient ends up completely dependent of care.
Fig. 1: Course of Alzheimer disease [after Gauthier 1999]
Criteria for the severity of a dementia
- Work and social activities limited
- Independent living maintained with appropriate personal hygiene and judgment intact
- Capable of living independently, but with some difficulties
- Certain measure of supervision required
- Activities of daily life are compromised
- Constant care and attention necessary
- Incapable of maintaining minimum standards of personal hygiene