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Dealing with cognitive decline – a public health emergency in ageing populations
The identification of effective preventive strategies to slow cognitive decline and postpone the diagnosis of dementia and its more frequent form, Alzheimer’s disease (AD), has become a public health emergency in ageing populations throughout the world. Indeed, there is no etiological treatment for AD available yet, and the strongest risk factors for dementia and AD – being older or carrying susceptibility genes – are not able to be modified. Yet, epidemiological studies indicate that there might be a room for prevention of dementia and AD. Vascular and cardio-metabolic factors (such as hypertension, overweight/obesity) are strong risk factors for dementia and AD (especially in midlife), and these factors could be managed by improvement of the environment, in particular physical activity and a balanced nutrition. Hence, exercise and healthy diets might be successful candidates for the prevention of age-related cognitive impairments. In particular, greater intake of fruits and vegetables (F&V) as part of a healthy diet, have been consistently associated with lower risks of cognitive decline and AD dementia.
Current knowledge on F&V and brain ageing has been expanded by several studies highlighted in this Newsletter. First, novel findings from Kesse-Guyot and coll. suggest that an early exposure to a carotenoid-rich dietary pattern starting at midlife would have strong benefits for cognitive health later in life. Second, Yannakoulia and coll. and Pastor-Valero and coll. suggest that diet quality might not be considered alone for the maintenance of cognitive performances, but within a cluster of healthy behaviours with a potentially synergistic effect on cognitive health (i.e. higher F&V intakes, higher socio-demographic levels, higher practice of physical activity) – altogether defining a general healthy lifestyle.
Indeed, beyond dietary intakes, the social, cultural and traditional practices, and obviously their interactions, all certainly participate since midlife, or even earlier, to modulate disease risk. Understanding the complex interplay between individual environmental factors over the life-course and the genetic background in relation to cognitive ageing certainly constitute a new challenge for future research. Hopefully, a more holistic vision of disease risk will lead to design optimal multimodal interventions for the prevention of AD and dementia, which will eventually help lowering the burden of the devastating disease.