Dementia: Physical activity of any intensity may help lower death risk
Share on Pinterest Scientists have found cognitive benefits from regular exercise for people at risk for dementia. sofie delauw/Stocksy Exercise is related to many health benefits, and researchers are interested in discovering how physical activity affects specific sub-populations. One study suggests that people who maintain or start physical activity after receiving a dementia diagnosis may be at decreased risk for all-cause mortality. People with dementia can work with doctors, physical therapists, and caregivers to implement helpful physical activity routines. Physical activity can offer multiple benefits , from weight management to decreasing the risk of heart disease. It may also help lower the risk of developing dementia. Another area of interest is the effects of physical activity after dementia has already been diagnosed. A study published in the British Journal of Sports Medicine evaluated the relationship between levels of and changes in physical activity and mortality among people with dementia. The researchers found that maintained physical activity before and after diagnosis was associated with the lowest mortality risk. All levels of sustained physical activity were associated with decreased mortality risk. In addition, the researchers found that starting physical activity after a dementia diagnosis could reduce mortality risk by 20% or more. The results suggest that exercise should be greatly encouraged among people with dementia. As noted by the study authors, Alzheimer’s disease is in the top ten leading causes of death, and the number of people with dementia is continuing to increase. This study aimed to explore how physical activity before and after dementia diagnosis affected mortality risk, taking into account the level and amount of physical activity. The study was a nationwide population-based cohort study. Researchers utilized the Korean National Health Insurance System Database to gather information. The study included over 60,000 individuals ages 40 or older who had received a dementia diagnosis between 2010 and 2016. All participants had gotten health check-ups within two years before and after their dementia diagnosis. The researchers identified people who had dementia based on their use of anti-dementia medications and certain scores that assess dementia. They assessed physical activity using data from the International Physical Activity Questionnaire. The researchers were then able to break down physical activity levels after dementia diagnosis into categories of vigorous, moderate, and light physical activity and note the amount of exercise per week. They defined regular physical activity as engaging in vigorous physical activity for twenty minutes or more at least three times weekly or engaging in moderate physical activity for thirty minutes or more at least five times weekly. They then noted how participants’ activity levels changed before and after dementia diagnosis. The average follow-up time was 3.7 years, and during this time, 16,431 participants died. The researchers were able to look at how physical activity related to all-cause mortality. Overall, the researchers observed “a dose-response association between an increased amount of PA [physical activity] and a decreased risk of all-cause mortality.” 29% decrease in mortality risk The researchers observed that participants who kept doing regular physical activity before and after dementia diagnosis saw the lowest mortality risk compared to participants who remained inactive, with a 29% reduction in mortality risk. Compared to non-active participants, participants who increased their physical activity to at least 1,000 metabolic equivalent of tasks (METs)-minutes a week saw a reduced mortality risk. METs have to do with measuring the amount of energy required to perform physical activities. The researchers also observed a 3% mortality risk reduction for every 100 METs-minutes per week that participants increased physical activity following their dementia diagnosis. There was also a slight reduction in mortality risk for participants with all-cause dementia and Alzheimer’s disease who ceased regular physical activity after diagnosis. When looking at intensity levels of physical activity, researchers observed that in participants with all-cause dementia and Alzheimer’s disease, maintaining physical activity helped decrease mortality risk, with similar risk reductions in categories of light, moderate, and vigorous physical activity. Among participants with vascular dementia, researchers saw that sustained light or vigorous physical activity was linked to lower mortality risk. Eric D. Vidoni, PT, PhD, an associate professor of neurology with the KU Medical Center, the University of Kansas, who was not involved in the study, noted the following about the study’s findings to Medical News Today: “Capturing dementia diagnoses and physical activity on a national level adds compelling evidence to what we already know — that maintaining physical activity supports health, even after a dementia diagnosis. [O]ne of the interesting findings in this study was that light activity held almost as much benefit as moderate and vigorous activity.” Some limitations exist for this research. First, the study focused on Korean individuals, so there should be caution in generalizing the findings. Additional research with greater diversity could be helpful. Over 60% of participants were women, so it may also be helpful to include more men in future research. Second, physical activity levels and other lifestyle habits relied on self-reports from participants, which could have had varying levels of accuracy. However, participants could receive help from caregivers in answering questions. It is also possible that people who had less severe dementia and better functionality were more likely to maintain their physical activity levels. Thirdly, researchers acknowledge that reverse causality is possible. Fourth, using administrative data to note dementia might not perfectly match actual dementia diagnoses. The researchers also lacked data on the type of physical activity that participants did