Dr Dominic Holland and his team from the University of California, San Diego, studied 723 people aged between 65 and 90. Participants included 222 cognitively healthy people, 345 people with mild cognitive impairment and 156 people with Alzheimer’s disease.
The researchers used structural MRI and cognitive tests to assess changes in the participants over time.
The researchers found that there was a pronounced reduction in rates of clinical decline and atrophy with age for people with Alzheimer’s disease and mild cognitive impairment. In people who were cognitively healthy, rates of clinical decline and atrophy increased with age.
Dr Holland told GP that correct early diagnosis would lead to better care. ‘One of the key features for the clinical determination of Alzheimer's disease is its relentless progressive course, he said. ‘Patients typically show marked deterioration year after year.’
Dr Holland said that if older patients were not showing the same deterioration from one year to the next, clinicians may be hesitant to diagnose Alzheimer’s disease.
‘The trick is to be more attentive to patient change and aware of the age effect so as to more correctly distinguish the slower deterioration resulting from Alzheimer's disease occurring in older elderly from the slow decline accompanying normal ageing in this age group.’
He added: ‘Appropriate care for someone who is cognitively normal, though old, and for someone who is old and in the early stages of dementia are different requirements.'