Exercise and mindfulness do not appear to improve cognitive function in older adults

Abstract: While exercise and mindfulness help older adults stay physically fit and mentally healthy, they may not have as strong a beneficial effect on cognition as previously believed.

Source: WUSTL

A large study that focused on whether exercise and mindfulness training could boost cognitive function in older adults found no such improvement after either intervention.

Researchers from the Washington University School of Medicine in St. Louis and the University of California, San Diego studied the cognitive effects of exercise, mindfulness training, or both for up to 18 months in older adults who reported age-related changes in memory but were not diagnosed with any form of dementia.

The findings were published in PIT.

“We know beyond a shadow of a doubt that exercise is good for older adults, that it can reduce the risk of heart problems, strengthen bones, improve mood and have other beneficial effects – and it was thought that it could also improve cognitive function,” he said. first author of the study, Eric J. Lenze, MD, Wallace and Lucille Renard Professor and Chair of the Department of Psychiatry at the University of Washington.

“Also, mindfulness training is beneficial because it reduces stress, and stress can be bad for your brain. So we hypothesized that if older adults regularly exercised, practiced mindfulness, or both, there might be cognitive benefits—but that’s not what we found.”

Lenze and his colleagues still want to see if there are any cognitive effects over a longer period of time, so they plan to continue studying this group of older adults to see if exercise and mindfulness can help prevent future cognitive declines. In this study, however, the practices did not boost cognitive function.

“So many older adults are concerned about memory,” said senior author Julie Wetherell, PhD, professor of psychiatry at UC San Diego.

“It’s important for studies like ours to develop and test behavioral interventions to try to provide them with neuroprotection and stress reduction, as well as general health benefits.”

Researchers studied 585 adults between the ages of 65 and 84. None had been diagnosed with dementia, but all were concerned about minor memory problems and other age-related cognitive declines.

“Minor memory problems are often considered a normal part of aging, but it’s also normal for people to worry when they notice these problems,” said Lenze, who also directs the University of Washington’s Healthy Mind Lab.

“The main goal of our lab is to help older people stay healthy by focusing on maintaining their mental and cognitive health as they age, and we wanted to see if exercise and mindfulness could offer a cognitive boost in the same way they promote other aspects of health.”

All study participants were considered cognitively normal for their age. Scientists tested them when they joined the study, measuring memory and other aspects of thinking. They also performed a brain scan.

The participants were randomly assigned to one of four groups: the group in which the subjects worked with trained exercise instructors; a group under the supervision of trained experts in the practice of mindfulness; the group that participated in regular exercise and awareness training; and a group that did neither, but met in occasional meetings focused on general health education topics. The researchers conducted memory tests and follow-up brain scans after six months and again after 18 months.

After six months and again after 18 months, all groups looked similar. All four groups performed slightly better on the test, but the researchers believe this was due to practice effects as subjects retook tests similar to the ones they had taken. Likewise, brain scans revealed no differences between the groups that would suggest a brain training benefit.

Lenze said the study results don’t mean that exercise or mindfulness training won’t help improve cognitive function in older adults, just that the practices don’t seem to improve cognitive performance in healthy, non-impaired people.

“We’re not saying ‘Don’t exercise’ or ‘Don’t practice mindfulness,'” Lenze explained.

“But we thought we might find a cognitive benefit in these older people. We didn’t. On the other hand, we have not studied whether exercise or mindfulness can benefit older people who are impaired, due to dementia or disorders such as depression. I don’t think we can extrapolate from the data that these practices don’t help anyone improve cognitive function.”

Lenze said the researchers plan to continue to follow the group of adults who participated in this study.

“They’re still practicing and thinking,” he said. “We didn’t see improvements, but cognitive performance didn’t decline either. In the next phase of the study, we will continue to follow the same people for another five years to see if exercise and mindfulness practice can help slow or prevent future cognitive decline.”

About this news about aging and cognition research

Author: Jim Dryden
Source: WUSTL
Contact: Jim Dryden – WUSTL
Picture: Image credited to WUSTL

Original research: Closed access.
“Effects of mindfulness and exercise training on cognitive function in older adults: a randomized clinical trial” by Eric J. Lenze et al. PIT

---

Abstract

Effects of mindfulness and exercise training on cognitive function in older adults: a randomized clinical trial

Importance Episodic memory and executive function are key aspects of cognitive functioning that decline with aging. This decline can be remedied by lifestyle interventions.

Goal To determine whether mindfulness-based stress reduction (MBSR), exercise, or a combination of both improve cognitive function in older adults.

Design, setting and participants This 2 × 2 factorial randomized clinical trial was conducted at 2 sites in the USA (Washington University in St Louis and University of California, San Diego). A total of 585 older adults (aged 65 to 84 years) with subjective cognitive impairment but not dementia were randomized (enrollment November 19, 2015 to January 23, 2019; final follow-up March 16, 2020). .

Interventions Participants were randomized to undergo the following interventions: MBSR with a goal of 60 minutes of meditation per day (n = 150); exercise with aerobic components, strength components, and functional activities with a goal of at least 300 minutes per week (n = 138); combined MBSR and exercise (n = 144); or a control group of health education (n = 153). The interventions lasted 18 months and consisted of group lessons and home practice.

Main outcomes and measures The 2 primary outcomes were composites of episodic memory and executive function (standardized to mean [SD] from 0 [1]; higher composite scores indicate better cognitive performance) from neuropsychological testing; the primary endpoint was 6 months and the secondary endpoint was 18 months. There were 5 reported secondary outcomes: hippocampal volume and dorsolateral prefrontal cortex thickness and area from structural magnetic resonance imaging and functional cognitive capacity and self-reported cognitive problems.

the results Among 585 randomized participants (mean age 71.5 years; 424 [72.5%] women), 568 (97.1%) completed 6 months of the trial, and 475 (81.2%) completed 18 months. At 6 months, there was no significant effect of mindfulness training or exercise on episodic memory (MBSR vs. no MBSR: 0.44 vs. 0.48; mean difference, −0.04 points [95% CI, –0.15 to 0.07]; P= 0.50; exercise vs. no exercise: 0.49 vs. 0.42; difference 0.07 [95% CI, –0.04 to 0.17]; P= .23) or executive function (MBSR vs. no MBSR: 0.39 vs. 0.31; mean difference, 0.08 points [95% CI, –0.02 to 0.19]; P= 0.12; exercise vs. no exercise: 0.39 vs. 0.32; difference 0.07 [95% CI, –0.03 to 0.18]; P= .17) and there were no intervention effects at the secondary endpoint of 18 months. There was no significant interaction between mindfulness training and exercise (P= .93 for memory and P= .29 for executive function) at 6 months. Of the 5 prespecified secondary outcomes, none showed significant improvement with any intervention compared with those who did not receive the intervention.

Conclusions and relevance Among older adults with subjective cognitive problems, mindfulness training, exercise, or both did not result in significant differences in improvements in episodic memory or executive function at 6 months. Findings do not support the use of these interventions to improve cognition in older adults with subjective cognitive problems.

Trial registration ClinicalTrials.gov Identifier: NCT02665481