Determining the Effects of Lifestyle Factors Including Smoking, Alcohol Consumption, Physical Activity, and Diet on the Risk and Progression of Dementia: A Systematic Review

Dementia and cognitive decline among older adults are increasingly considered as a significant health burden with a high level of personal, societal, and economic implications. Understanding the influence of lifestyle factors and potential lifestyle modifications on the risk and progression of dementia may aid in offering a non-pharmacological approach to reducing this public health challenge. This study explores the impact of key lifestyle factors - diet, physical activity, smoking, and alcohol consumption - on both the risk and progression of dementia. A systematic literature review was conducted using a predefined search strategy. Studies were identified through searches of the databases PubMed, Scopus, Web of Science, Embase, Medline, and CINAHL. Studies published between 2014 and 2024 were included to capture recent evidence. The quality of the selected studies was assessed using the Newcastle-Ottawa Scale (NOS) for cohort studies and the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for cross-sectional studies. A total of 1,135 studies were initially identified; 12 met the inclusion criteria and were critically reviewed. The findings suggest that each lifestyle factor exerts an influence on the risk and progression of dementia, albeit to varying degrees. Further research is needed to deepen the understanding of these relationships and inform targeted preventive strategies.