Dementia

Introduction

Suspicion of a dementiais usually aroused by worries or reports either by the patient or a close relation. The first presentation is likely to be to the patient’s physician, who may have considerable knowledge of the patient’s medical history and social situation. This can be very helpful in assessing the likelihood that dementia may underlie presenting symptoms.

When the possibility of dementia exists, a differential diagnosis will be critical for the future clinical management of the disorder. The likelihood of a degenerative disorder may well be established initially in primary care, but because the differential diagnosis of a dementia will often require specialised techniques and procedures, it will generally be completed following referral to secondary care where both facilities and expertise are available as required.

Alzheimer's disease (AD) is the most common dementia, it accounts for 50–75% of dementia cases and is thought to affect 5–8% of people over the age of 65 years. AD usually develops slowly yet steadily over a number of years. From the time of diagnosis, people with AD generally live for between 6 and 8 years, although some people do live as long as 20 years.