Promoting Successful Cognitive Aging: A Ten-Year Update

Abstract

A decade has passed since we published a comprehensive review in this journal addressing the topic of promoting successful cognitive aging, making this a good time to take stock of the field. Because there have been limited large-scale, randomized controlled trials, especially following individuals from middle age to late life, some experts have questioned whether recommendations can be legitimately offered about reducing the risk of cognitive decline and dementia. Despite uncertainties, clinicians often need to at least make provisional recommendations to patients based on the highest quality data available. Converging lines of evidence from epidemiological/cohort studies, animal/basic science studies, human proof-of-concept studies, and human intervention studies can provide guidance, highlighting strategies for enhancing cognitive reserve and preventing loss of cognitive capacity. Many of the suggestions made in 2010 have been supported by additional research. Importantly, there is a growing consensus among major health organizations about recommendations to mitigate cognitive decline and promote healthy cognitive aging. Regular physical activity and treatment of cardiovascular risk factors have been supported by all of these organizations. Most organizations have also embraced cognitively stimulating activities, a heart-healthy diet, smoking cessation, and countering metabolic syndrome. Other behaviors like regular social engagement, limiting alcohol use, stress management, getting adequate sleep, avoiding anticholinergic medications, addressing sensory deficits, and protecting the brain against physical and toxic damage also have been endorsed, although less consistently. In this update, we review the evidence for each of these recommendations and offer practical advice about behavior-change techniques to help patients adopt brain-healthy behaviors.

Keywords: Cognitive aging; cognitive decline; cognitive reserve; dementia; healthy aging; healthy lifestyle; mild cognitive impairment; preventive medicine; risk reduction.

Fig. 1

Model of cognitive decline. The black line represents the trajectory of cognitive decline due to neurodegenerative disease. The yellow dashed line represents the threshold for clinical dementia, i.e., the inability to manage activities of daily living. The red line represents the impact of additional injuries to the brain, which can decrease brain reserve and cause a leftward shift of the trajectory of cognitive decline, leading patients to cross the threshold for clinical dementia earlier. The green line represents the effect of increased cognitive and brain reserve, which can cause a rightward shift in the trajectory of cognitive decline, leading patients to cross the threshold for clinical dementia later. These principles involving theoretical shifts in the trajectory of cognitive decline also apply to adults without neurodegenerative disease, though the initial downward trajectory is much less steep.