14 DAY TRIAL // Lower intelligence and even premature death are associated with inflammation, found a team of Swedish scientists from the Karolinska Institute in Stockholm.
The research was recently published in Brain, Behavior and Immunity and was funded by the Stanley Medical Research Institute, Bethesda, MD, USA, the Swedish Research Council, and the Swedish Council for Working Life and Social Research.
Data collected over several years from large population-based registers, allowed scientists to measure inflammation as well as intelligence at 18-20 years of age in nearly 50,000 young men, and to follow deaths over the next 35 years.
Dr Hakan Karlsson, who is the lead researcher of the study, said that even though it was well known that inflammation associated with infection or cardiovascular disease could affect brain function, “this is the first time that similar associations have been shown in healthy young people, which suggests that even low levels of inflammation can have detrimental consequences for health and brain function.”
He added that even after excluding people with signs of current illness. “those with low-grade inflammation performed more poorly on standardized intelligence tests.”
What is even a more concerning matter is that “inflammation also predicted an increased risk of premature death, and since low-grade inflammation appears to be hazardous, it is also important to determine its causes.”
Dr Karlsson said that an important role could have been played by childhood environment, because in this specific research, childhood socio-economic status predicted the level of inflammation that was observed.
The example that is given is about children of farmers, that had higher levels of inflammation than those whose fathers were non-manual workers.
“It’s possible that these boys were exposed to more toxins, allergens or infectious agents in childhood, leading to greater inflammation and its negative effects later in life,” Dr Karlsson assumes.
Finally, Dr Michelle Luciano, from the Center for Cognitive Aging and Cognitive Epidemiology at the University of Edinburgh, estimated that “this is an important finding because it is the largest study to date to show that low-grade inflammation in young adulthood is associated with intelligence and mortality.”
“An interesting question now is whether the effects of a less healthy childhood environment on inflammation persist into middle age and beyond,” she added.