Effects of multidomain lifestyle interventions on cognitive decline and Alzheimer's disease prevention: A literature review and future recommendations

Alzheimer's disease (AD) is a neurodegenerative disorder with an increasing incidence and currently without a cure. It is speculated that targeting multiple modifiable risk factors (MRFs) could be a beneficial strategy for the prevention of cognitive decline and AD. This study provides an overview and discusses the existing literature on multidomain lifestyle interventions in relation to cognitive decline and the prevention of AD. A literature search was performed in PubMed and Scopus, for studies published in English up to 31 May 2021. We identified nine relevant studies on the effect of multidomain lifestyle interventions on cognition (n = 8) and/or AD incidence or risk scores (n = 4). The studies included a combination of the separate intervention components diet (n = 8), physical activity (n = 9), cognitive activity (n = 6), metabolic or cardiovascular risk factor reduction strategies (n = 8), social activity (n = 2), medication (n = 2), and/or supplementation (n = 1). Global cognition was improved significantly in four of the eight studies that had global cognition as the outcome. Moreover, significant improvements were shown for cognitive domains in two of the three studies with specific cognitive domains as an outcome. No effect on AD incidence was observed, although positive results were shown for AD risk scores. The results suggest that multidomain lifestyle intervention studies may be partially effective in preventing cognitive decline. However, studies were heterogeneous and limited in follow-up. Future research on the effect of multidomain lifestyle interventions on cognitive decline and AD incidence must be conducted with a longer follow-up period.