Researchers at King’s College London have identified several cardiovascular risk factors, including smoking and high blood pressure, which may be linked to the accelerated decline of memory, learning, attention and reasoning in older adults.
The study found that participants over the age of 50 who smoked, had high blood pressure or were most at risk of suffering a stroke, performed more poorly on a range of tasks designed to test memory recall, verbal fluency, attention and other cognitive outcomes.
The study explores the combined effect of multiple risk factors on cognitive decline in older adults. Researchers say the findings indicate that future clinical trials looking at cognitive decline should focus on the combination of these risk factors rather than individual triggers.
Using a sample of more than 8,000 adults, the researchers analysed data on smoking, blood pressure, cholesterol levels and Body Mass Index (BMI), as well as cardiovascular and stroke risk scores which are used to determine the probability of someone developing heart disease or stroke.
At four and eight year follow-ups, participants undertook two tests of cognitive performance, including memory and executive functioning, which were then combined into an overall ‘cognitive index’ score. The memory task involved learning ten unrelated words before immediate and delayed recall was tested. For the assessment of executive functioning, participants were asked to name as many animals as possible in one minute to examine verbal fluency and to cross-through specified letters in a series to measure attention, mental speed and visual scanning.
The study showed that smoking was linked with lower cognitive performance in all three tests after four years. Participants with high BMI, blood pressure and stroke risk scores performed less well on cognitive tasks, although this varied across the three tests.
Dr Alex Dregan, Lecturer in Translational Epidemiology and Public Health at King’s College London, said: “Cognitive decline becomes more common with ageing and for an increasing number of people interferes with daily functioning and well-being. Some older people can become forgetful, have trouble remembering common words or have problems organising daily tasks more than others. We have identified a number of risk factors which could be associated with accelerated cognitive decline, all of which could be modifiable. This offers valuable knowledge for future prevention and treatment interventions.”
Read more about this study on King’s College London’s website.