Alzheimer disease (AD) and related dementia (ADRD) are devastating diseases that affect over 55 million people worldwide and impose an estimated economic burden of over $800 billion annually.¹ This figure is projected to increase as the global population ages, with the prevalence of AD/ADRD expected to triple over the next 30 years.¹ To date, there is no cure to stop or reverse disease progression, underscoring the critical need for the development of primary or secondary prevention strategies that target modifiable risk factors to delay or prevent the onset of clinical symptoms.

Over the past decade, there has been ever-growing, yet controversial, evidence in the role of modifiable risk factors and risk reduction strategies for dementia. This is exemplified by the conflicting conclusions from 2 recent commissioned reports.^2,3 The National Academy of Medicine report² concluded in 2017 that the evidence from large randomized clinical trials (RCTs)鈥攖he criterion standard for evaluating an intervention鈥檚 effectiveness鈥攊s insufficient to support a public health campaign for dementia prevention. However, the report identified 3 intervention strategies with potential benefits: cognitive training, blood pressure management for people with hypertension, and physical activity. In contrast, the 2020 Lancet Commission report³ advocated for a more ambitious and aggressive approach to prevention, based on evidence from both observational studies and RCTs, concluding that 40% of worldwide dementia cases could be prevented or delayed by modifying 12 risk factors: low education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, low social contact, excessive alcohol consumption, traumatic brain injury, and air pollution. Although the discrepancies between these reports underscores the complexity of translating research evidence into both individual and policy recommendations, risk reduction interventions remain a promising, inexpensive, and relatively safe strategy for lowering dementia risk.