Memory loss is one of the very few symptoms that may signal which 70-year-olds risk developing dementia, according to a doctoral thesis at the Sahlgrenska Academy at the University of Gothenburg, Sweden.

Several of the tests previously used to predict which elderly individuals risk developing dementia do not seem to work any longer, according to the thesis, which shows that memory loss is the only factor that can still be used to indicate who is at risk, although not among the very old.

The study compared nondemented 70-year-olds examined in the early 1970s with nondemented 70-year-olds examined in the year 2000. The results show that those who were examined in 2000 scored much higher on psychological tests than those examined 30 years earlier, say the researchers. This finding clearly indicates that such tests can no longer be used to predict future dementia, they add.

– In the early 1970s, several different tests could be used to predict people’s risks of developing dementia, but today it seems like psychiatric evaluation of the memory is the only useful test, say the researchers. In addition, it is more difficult to predict dementia the higher the person’s level of education, says Simona Sacuiu, MD, PhD, who authored the thesis.

The follow-up of the 70-year-olds five years later showed that 5% had developed dementia, according to the study. Those with memory problems showed an increased risk of developing dementia, although not everybody with poor memory developed dementia. Consequently, the link between forgetfulness and future dementia is more complex than commonly thought, the researchers say. Memory loss among elderly individuals may, but doesn’t have to be, an early sign, they add.

– In order to effectively detect dementia at an early stage, we need a useful tool that includes several types of tests, but the tests need continuous adjustments since the elderly of today perform much better at standardized psychological tests than previous generations, Sacuiu says.

Examinations of a group of nondemented 85-year-olds show that the link between memory problems and dementia is not as clear in this age group, say the researchers. The 85-year-olds’ ability to find words, to copy a geometric figure and to take quick decisions were some qualities that were evaluated in a psychiatric assessment. More than 300 individuals participated in the study, of which 17% had developed dementia 3 years later, according to the researchers.

– We can’t say that memory loss is the only meaningful sign of future dementia among 85-year-olds, since other symptoms, such as difficulties finding words or drawing a geometric figure, were needed for their risk of developing dementia to increase, Sacuiu says.

H70, short for Health 70, is a unique population study at the Sahlgrenska Academy, according to the researchers. The study was started in 1971 with an assessment of 70-year-olds. The individuals were followed up regularly for 30 years. A new H70 study was started in the year 2000. Its participants will be followed up again during 2009 at age 79. The study includes data on over 2000 residents of Gothenburg, Sweden. The participants have been examined physically and mentally, and have made it possible for several research teams to pinpoint various trends in physical and mental health in the ageing population.

For more information, contact: Sacuiu via e-mail.

Doctoral thesis for the degree of Doctor of Philosophy (Medicine) at the Sahlgrenska Academy at University of Gothenburg, Institute of Neuroscience and Physiology, Neuropsychiatric Epidemiology Unit. Title of the thesis: Prodromal Cognitive Signs of Dementia

[Source: University of Gothenburg Web site]