Physical activity of any intensity can help reduce the risk of death

• Exercise is associated with many health benefits, and researchers are interested in understanding how physical activity affects specific subpopulations.
• A study suggests that people who maintain or start physical activity after receiving a dementia diagnosis may have a lower risk of all-cause mortality.
• People with dementia can work with doctors, physical therapists, and caregivers to implement helpful physical activity routines.

Physical activity can provide several advantagesfrom controlling weight to reducing the risk of heart disease. It can also help reduce the risk to suffer from dementia. Another area of ​​interest is the effects of physical activity after dementia has already been diagnosed.

The researchers found that maintaining physical activity before and after diagnosis was associated with the lowest risk of mortality. All levels of sustained physical activity were associated with reduced mortality risk.

Additionally, researchers found that starting physical activity after a diagnosis of dementia could reduce the risk of mortality by 20% or more. The results suggest that exercise should be strongly encouraged in people with dementia.

As the study authors noted, Alzheimer's disease is one of the top ten causes of death and the number of people with dementia continues to increase. The aim of this study was to examine how physical activity before and after dementia diagnosis affected mortality risk, taking into account the level and quantity of physical activity.

The study was a nationwide population-based cohort study. The researchers used the Korean National Health Insurance System database to collect information. Over 60,000 people aged 40 and over who had received a dementia diagnosis between 2010 and 2016 took part in the study. All participants had undergone a health examination within two years before and after their dementia diagnosis.

The researchers identified people with dementia based on their use of anti-dementia medications and certain scores to 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 physical activity per week. They defined regular physical activity as vigorous physical activity for twenty minutes or more at least three times per week or moderate physical activity for thirty minutes or more at least five times per week.

They then determined how participants' activity levels changed before and after their dementia diagnosis. The average follow-up time was 3.7 years and during this time 16,431 participants died. The researchers were able to examine how physical activity is related to all-cause mortality.

Overall, the researchers observed “a dose-response relationship between increased amounts of PA.” [physical activity] and a lower risk of all-cause mortality.”

Researchers observed that participants who continued to exercise regularly before and after dementia diagnosis had the lowest risk of mortality compared to participants who remained inactive, with a 29% reduction in mortality risk.

Compared to inactive participants, participants who increased their physical activity to at least 1,000 metabolic equivalent task (METs) minutes per week had a lower risk of mortality. METs involve measuring the amount of energy required to perform physical activities.

Researchers also observed a 3% reduction in mortality risk for every 100 MET minutes per week when participants increased their physical activity after their dementia diagnosis. There was also a slight reduction in mortality risk for participants with all-cause dementia and Alzheimer's disease who stopped regular physical activity after diagnosis.

When looking at the intensity of physical activity, the researchers found that among participants with all-cause dementia and Alzheimer's disease, maintaining physical activity helped reduce the risk of mortality, with similar reductions in risk in the light, moderate and vigorous physical activity categories became. In participants with vascular dementia, researchers found that sustained light or vigorous physical activity was associated with a lower risk of mortality.

Eric D. Vidoni, PT, PhD, associate professor of neurology at the University of Kansas KU Medical Center, who was not involved in the study, noted the following about the study's findings: Medical News Today:

“Recording dementia diagnoses and physical activity at a national level provides compelling evidence of what we already know – that maintaining physical activity promotes health, even after a dementia diagnosis. [O]One of the interesting findings of this study was that light activity was almost as beneficial as moderate and vigorous activity.”

There are some limitations to this research. First, the study focused on Korean individuals, so caution is warranted when generalizing the results. Additional research with greater diversity could be helpful. Over 60% of participants were women, so it might also be helpful to include more men in future research.

Second, physical activity levels and other lifestyle habits relied on participants' self-reports, which could vary in accuracy. However, participants could receive help from supervisors in answering questions. It is also possible that people with less severe dementia and better functionality were more likely to maintain their physical activity levels.

Third, researchers recognize that reverse causality is possible. Fourth, the use of administrative data to determine dementia may not accurately correspond to actual dementia diagnoses.

The researchers also lacked data on participants' type of physical activity, and the questionnaire used may not have accurately identified shorter periods of physical activity, which are still part of overall physical activity. Therefore, it is possible that researchers misclassified or underestimated physical activity.

The definition of regular physical activity did not include light physical activity, and the researchers considered participants “who did not engage in moderate or vigorous physical activity to be physically inactive.” Therefore, additional follow-up may be required and this definition may have impacted certain analyses.

Finally, the researchers only worked with data from two check-ups, each within two years of the dementia diagnosis: one before and one after. They point out that the course and severity of dementia was likely mild in most participants during the study. Therefore, it might be helpful to look at additional data on people with advanced dementia.

Overall, the study highlights another potential benefit of exercise, particularly for people diagnosed with dementia. The results suggest that even lower levels of physical activity may help reduce mortality in this at-risk population, and the study authors also note that people with dementia are less likely to receive adequate levels of physical activity.

Incorporating more physical activity will look different in every situation. People with dementia can receive support from caregivers and health professionals in implementing appropriate training strategies.

Ryan Glatt, MS, CPT, NBC-HWC, senior brain health coach and director of the FitBrain program at the Pacific Neuroscience Institute at Providence Saint John's Health Center in Santa Monica, California, who also was not involved in the study, noted the following: MNT:

“If these findings are implemented, they could inform care strategies that promote different forms of physical activity – light, moderate or vigorous – tailored to individual abilities and preferences. This approach could potentially extend the life expectancy of people with dementia and provide a useful, non-pharmacological strategy in dementia management.”

“Supporting physical activity in people with dementia can be achieved through various options, such as group classes in community centers, online resources with tailored routines or sessions with trained therapists, all enhanced by consistency of routines and the encouragement of an exercise partner. “Together, these strategies make exercise safe, engaging and accessible for people with dementia at any fitness level.”
— Ryan Glatt, MS, CPT, NBC-HWC

Prof. Nicola Veronese, Associate Professor of Geriatrics and Internal Medicine at Saint Camillus International University of Health Sciences, Rome, Italy, also pointed out the following strategies to improve physical activity levels in this population: