New study suggests high blood pressure, diabetes affect thinking, memory more in mid-age than after 70

In one of the largest cross-sectional studies till date, a group of researchers at the Nuffield Department of Clinical Neurosciences, University of Oxford, have found that high blood pressure and diabetes in mid-life can hamper thinking speed and memory.The findings of the study, published in the peer-reviewed journal Nature Communications, suggest that the cognitive abilities of those in the age range of 44 to 69 are most affected by high blood pressure while those above the age of 70 did not have such a negative impact on their cognition.Though earlier studies have shown the effect of blood pressure and diabetes on dementia risk in later life, this study shows that the effects (however minute) can be noted in mid-life too.The study suggests that controlling these risk factors may be a good way to reduce the risk of dementia in older age.The studyFor the latest study, researchers included over 22,000 participants from the UK biobank study (a project that is aimed to study the effect of genetics and epidemiological associations with disease risks). The volunteers were between the age of 44 and 73 with a mean age of 62 years.About 5 percent of all participants were diabetic, 21 percent were taking cholesterol-lowering medications and 22 percent were taking antihypertensive medications. Almost 78 percent of the volunteers were non-smokers.The short term memory of all the participants was checked using a pair-matching test while the speed of their mental processing was tested using the reaction time. Brain scans were done on the same day as the study to get a better understanding of what is going on.The resultsThe researchers noted three things in the study -- the association of each risk factor on a continuous measure of executive function, the effect of modifying the risk (for example those taking antihypertensive medications), the relationship between age-related changes in the neuronal network in the frontoparietal areas of the brain (the area associated with executive and cognitive control) and age and cerebrovascular risk factors. The following things were noted in the study:

• Age had the strongest association with cerebrovascular risk factors, followed by intake of antihypertensive medications and having diabetes. The link being strongest in the age range of 44 to 69 years and weak above the age of 70. Changes in cognition were very small and the mental processing was delayed by only a fraction of seconds. However, it was still significant, considering signals take milliseconds to travel through the brain.
• In those who took antihypertensive medication, cognitive decline was seen when the systolic blood pressure increased above 140 mmHg. Normal systolic blood pressure is 120 mmHg.
• When controlled for age, the link between systolic blood pressure and executive function was significant in the mid-life group for both who took antihypertensive medications and those who didn’t.
• Brain scans done to study show changes in brain structure, especially in the frontoparietal brain network. 

Explaining the effect of these changes in brain structure, Dr Michele Veldsman, a postdoctoral researcher at the Department of Experimental Psychology, Oxford University and a co-author of the study, said in a news release, “The MRI scans show that raised blood pressure and glucose seem to alter both the grey matter and the white matter connections in the brain.’“These changes seem to have a direct impact on the speed of thinking and short-term memory,” added the other author Dr Xin You Tai, a DPhil student at the Nuffield Department of Clinical Neurosciences.For more information, read our article on Dementia.Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.