More steps, moderate physical activity reduces dementia, risk of cognitive impairment – Zoo House News
According to a new study from the Herbert Wertheim School of Public Health and Human Longevity Science at the University of California San Diego.
In the January 25, 2023 online edition of Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, the team reported that in women age 65 and older, every additional 31 minutes of moderate-to-vigorous physical activity per day was associated with a 21 percent increase lower risk of developing mild cognitive impairment or dementia. The risk was also 33 percent lower with each additional 1,865 daily steps.
“Given that dementia onset is 20 years or more before symptoms appear, early intervention to delay or prevent cognitive decline and dementia in older adults is essential,” said senior author Andrea LaCroix, Ph. D., MPH, Distinguished Professor at the Herbert Wertheim School of Public Health and Human Longevity Science at UC San Diego.
Although there are several types, dementia is a debilitating neurological condition that can result in loss of memory, thinking, problem solving, or reasoning. Mild cognitive impairment is an early stage of memory loss or thinking disorders that is not as severe as dementia.
According to the US Department of Health and Human Services, more than 5 million people in this country are affected by dementia. This number is expected to double by 2050.
More women live with dementia and are at higher risk of developing dementia than men.
“Physical activity has been identified as one of the top three most promising ways to reduce the risk of dementia and Alzheimer’s. Prevention is important because dementia, once diagnosed, is very difficult to slow or reverse. There is no cure,” LaCroix said.
However, because few large studies have examined device measures of exercise and sitting in relation to mild cognitive impairment and dementia, much of the published research on the associations of physical activity and sedentary behavior with cognitive decline and dementia is based on self-reported measures. said first author, Steven Nguyen, Ph.D., MPH, a postdoctoral fellow at the Herbert Wertheim School of Public Health.
For this study, researchers collected data from 1,277 women as part of two supplemental Women’s Health Initiative (WHI) studies—the WHI Memory Study (WHIMS) and the Objective Physical Activity and Cardiovascular Health (OPACH) study. The women wore research-grade accelerometers and went about their daily activities for up to seven days to get accurate measurements of physical activity and sitting.
The activity trackers showed the women an average of 3,216 steps, 276 minutes of light physical activity, 45.5 minutes of moderate to vigorous physical activity, and 10.5 hours of sitting per day. Examples of light physical activity are housework, gardening or walking. Moderate to vigorous physical activity may include brisk walking.
The study results also showed that higher levels of sitting and longer periods of sitting were not associated with a higher risk of mild cognitive impairment or dementia.
Taken together, this information has clinical and public health importance, as there is little published information on the amount and intensity of physical activity required for reduced risk of dementia, Nguyen said.
“Older adults can be encouraged to increase exercise of at least moderate intensity and take more steps each day to reduce the risk of mild cognitive impairment and dementia,” Nguyen said.
“The results for steps per day are particularly noteworthy as steps are recorded by a variety of wearable devices, which are increasingly being worn by individuals and could easily be adopted.”
The authors said more research is needed among large diverse populations that include men.
Co-authors include: John Bellettiere, UC San Diego; Kathleen M Hayden and Stephen R Rapp, Wake Forest University School of Medicine; Chongzhi Di, Fred Hutchinson Cancer Center; Priya Palta, Columbia University Irving Medical Center; Marcia L. Stefanick, Stanford University School of Medicine; JoAnn E Manson, Harvard Medical School; and Michael J. LaMonte, University at Buffalo-SUNY.
This research was funded in part by the National Institute on Aging (P01 AG052352, 5T32AG058529-03) and the National Heart, Lung, and Blood Institute (R01 HL105065). The Women’s Health Initiative was funded by the National Heart, Lung, and Blood Institute (75N92021D00001, 75N92021D00002, 75N92021D00003, 75N92021D00004, 75N92021D00005).