Prevention of dementia in seniors: meditation still under study

Meditation as a tool for preventing dementia and improving the mental health and well-being of the elderly is one of the avenues explored by the European research program Medit-Ageing, coordinated by Inserm © AdobeStock

Meditation as a tool for preventing dementia and improving the mental health and well-being of the elderly is one of the avenues explored by the European research program Medit-Ageing, coordinated by Inserm. As part of this program, researchers from Inserm and the University of Caen Normandy, in collaboration with French and European teams, have observed the impact of 18-month meditation training on certain brain structures involved in the regulation of attention and emotions, in healthy people over the age of 65. Their results, to be published in JAMA Neurology, testify to a positive impact on attentional and socio-emotional regulation capacities, but do not show significant benefits of meditation on the volume and functioning of the cerebral structures studied compared to the control groups. However, they call for continuing research on the whole brain, over longer periods of time and with more participants.

In order to prevent the onset of dementia in the elderly, recent intervention strategies are multidisciplinary and oriented towards improving the lifestyle of seniors. They include cognitive stimulation, physical activity, a healthy diet and cardiovascular recommendations. However, psychoaffective factors such as depression, stress or anxiety are not the subject of dedicated preventive interventions.

Mental training targeting the regulation of stress and attention – such as mindfulness meditation – has been shown to be a beneficial tool in managing the cognitive and emotional aspects specific to aging, in particular to reduce stress, anxiety and depression.

Recent work has reported that the insula and the anterior cingulate cortex are regions of the brain that are specifically sensitive to meditation training. These brain regions connected to each other are involved in particular in self-awareness, as well as the processing and regulation of attention, emotions and empathy. In young adults, meditation has already shown its capacity to modify structurally (in volume for example) and functionally these structures, in particular in expert meditators who have several thousand hours of practice.

The insula and the anterior cingulate cortex are especially sensitive to aging. It has been shown that, in elderly people who are experts in the practice of meditation, the volume of gray matter as well as glucose metabolism (a physiological process essential to the proper functioning of the brain) were greater than in people who do not practice meditation. meditation.

Meditation could therefore be an interesting approach to preserve brain structures and functions as well as cognitive abilities, and by extension, to prevent dementia.

A team of researchers from the European Medit-Ageing research group, led by Inserm research director Gaël Chételat of the Physiopathology and Imaging of Neurological Diseases laboratory (Inserm/University of Caen Normandy), in collaboration with teams from the Research Center in Neurosciences from Lyon (Inserm/CNRS/Université Claude Bernard Lyon 1/Université Jean-Monnet-Saint-Étienne), University College London, University of Liège and University of Geneva, interested in the potential physiological, cognitive and emotional benefits of meditation in seniors.

Within the Age-Well clinical trial involving 136 participants aged 65 or over with no known pathology, the researchers measured the impact of an 18-month meditation intervention on the volume and tissue perfusion (physiological process supplying an organ with the nutrients and oxygen necessary for its metabolism) of the insula and the anterior cingulate cortex. They were also interested in certain cognitive and socio-affective parameters.

Three groups of participants were formed in order to compare the possible benefit of meditation compared to different types of interventions. The first group followed the protocol relating to the meditation intervention (mindfulness meditation and “love and compassion” meditation), the second group constituting an “active control” group followed a learning period of the English and the third group constituting a “passive control” group did not follow any intervention.

At the end of the 18 months of intervention, the researchers did not observe any significant difference in volume or perfusion of the cingulate cortex or the insula in the group practicing meditation compared to the control groups.

“The fact that no anatomical differences were observed between these two groups may indicate that, while meditation may alter the volume of younger, more plastic brains, 18 months of meditation training is not sufficient to alter the effects of aging, Gael Chetelat analysis. Moreover, if the volume measurement results are strictly negative, those of the perfusion show a tendency in favor of meditation that it could be interesting to explore over a longer intervention time and/or with a sample of larger population, says the researcher.

The research team therefore set up a 4-year follow-up of the participants in this trial, to analyze the possible long-term effects.

Conversely, significant differences were observed on behavioral measures between the meditation group and the English learning group, with better regulation of attention and socio-emotional abilities among participants in the meditation group. meditation.

“The practice of meditation shows here its real benefit on the mental health of the elderly, with a significant improvement in parameters specific to well-being and development, but also to the maintenance of attentional and socio-emotional capacities reported by the attendees”, adds Antoine Lutz, head of the Meditation axis of the study.

More specific measurements and analyzes will be conducted within the Age-Well trial to improve understanding of these mechanisms. They could make it possible to determine the measures most sensitive to the practice of meditation and to study the mechanisms of its effects.