opposite relationships with dementia
Watching television may increase the risk of dementia, while using a computer may reduce the risk, new research suggests.
The association of dementia with these activities remained strong regardless of how much physical activity a person engaged in, the authors wrote in the journal. Proceedings of the National Academy of Sciences.
Television viewing and computer use are associated with an increased risk of chronic disease and death, while exercise and physical activity have been shown to be beneficial in reducing cognitive decline, structural brain atrophy and the risk of dementia in the elderly, the authors wrote.authors.
The authors said they wanted to try to understand the effects of television viewing and computer use on dementia risk, as people in the United States and Europe do both activities more often.
The researchers concluded that dementia is potentially influenced not by sitting due to sedentary behavior, but by what people do while sitting.
Some of the results were surprising, said first author David Raichlen, Ph.D., Ph.D., professor of human and evolutionary biology at University of Southern California, In the United States of America.
Previous literature on sedentary behavior has documented its negative effects on a wide range of health outcomes, rather than finding positive associations, the researcher explained.
More than 140,000 participated in the survey
The researchers conducted their prospective cohort study using data from UK Biobank from UK. After excluding people under 60 years of age, those with dementia at the start of follow-up, and those without complete data, 146,651 participants were included.
Participants were followed from the first visit until they were diagnosed with dementia, died, lost to follow-up, or had their last hospital admission.
Time spent watching TV was associated with a higher risk of dementia (hazard ratio [RR] of 1.31; confidence interval [IC] 95% from 1.23 to 1.40), and computer use was associated with a lower risk of developing dementia (RR 0.80; 95% CI 0.76 to 0.85).
The relationship between television viewing and increased risk of dementia was greater among those who watched TV the longest compared to those who watched it the least time (RR 1.28; 95% CI 1.18 to 1.39).
Likewise, the relationship between a lower risk of dementia and computer use increased among those who used it the most.
Both average time and long time using a computer were associated with a lower risk of developing dementia (RR 0.70; 95% CI 0.64 to 0.76 and RR 0.76; 95% CI 0.70 to 0.83 , respectively).
Doctor. David pointed out that the high amount of television use in this study was four hours or more a day, and computer use – which involved leisure time rather than work – had benefits in terms of dementia risk after just half an hour.
These results remained significant after the researchers adjusted for demographic, health, and lifestyle variables such as time spent in physical activity, sleep, obesity, alcohol intake, smoking, diet score, education, body mass index, and job type.
Physical activity is still better than sedentary activity
The authors wrote that one potential reason for the different effects on dementia risk in the two activities studied is that sitting and watching TV is associated with “exceptionally low levels of muscle activity and energy expenditure compared to sitting and watching TV.” Computer”.
Dr. Andrew Budson, MD, Chief of Cognitive and Behavioral Neurology and Associate Chief of Staff for Education at VA Boston Health System, in the US, who was not involved in the study, said he believed a more likely explanation for the study’s findings lay in active tasks against passives necessary in the two types of activities the authors refer to.
“When we perform cognitive activities that involve using a computer, we use large parts of our cortex to perform that activity, whereas when we watch television, there are probably relatively small amounts of our brain that are actually active,” explained Dr. Andrija, author of the book Seven steps to manage your memory (free translation: Seven steps to take care of your memory) in the interview.
“This is one of the first times I was convinced that even when computer activity is not completely new and innovative, it can be useful,” said Dr. Andrija.
Physical activity would be much better, but if the choice is a sedentary lifestyle, active cognitive activities, such as using a computer, are better than watching TV, the researcher continued.
The results of the reviewed study are consistent with previous work, showing that the type of sedentary behavior is important, according to the authors.
“Several studies have shown that TV viewing time is associated with mortality and impairment of cardiometabolic biomarkers, whereas computer time is not,” the authors wrote.
A limitation of the study is that participants described their sedentary behavior through a questionnaire, and recall errors may occur.
“Using objective methods to quantify sedentary behavior and physical activity is necessary in future studies,” the researchers wrote.
The authors received support from National Institutes of Health, State of Arizona, Arizona Department of Health Services and gives McKnight Brain Research Foundation. Neither the authors nor Dr. Andrew Budson have a conflict of interest.
This content was originally published on MDedge.com – Medscape Professional Network.
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