A new study led by researchers from UCL suggests that dementia risk factors linked to cardiovascular health may have become more prominent over time compared to other factors like smoking or lower educational attainment. The research, published in The Lancet Public Health, examines shifts in the prevalence of dementia risk factors and their potential implications for future dementia rates.
Currently, approximately 944,000 individuals are living with dementia in the UK, with 52% of the population, or 34.5 million people, knowing someone diagnosed with the disease. Dementia remains a leading cause of death in the UK, especially among women, where it has been the top cause of death since 2011.
The study underscores a growing focus on modifiable risk factors, which, if eliminated, could theoretically prevent around 40% of dementia cases, according to UCL-led research. The researchers reviewed 27 papers, incorporating global data from 1947 to 2015, with the most recent study published in 2020. They assessed the data for dementia risk factors from each study and calculated the proportion of dementia cases attributable to each factor over time.
Dementia typically arises from a mix of genetic and environmental factors, including hypertension, obesity, diabetes, educational level, and smoking habits. The findings indicated that lower educational levels and smoking rates have declined over time, correlating with a decrease in dementia rates. Conversely, obesity and diabetes rates have climbed, paralleling an increase in their contribution to dementia risk.
Hypertension remains a significant dementia risk factor, although proactive management of this condition has also improved over time. Dr Naaheed Mukadam, the lead author from UCL Psychiatry, noted that cardiovascular risk factors have increasingly influenced dementia risk, warranting more focused intervention for future prevention efforts.
The study also highlights societal shifts—increased educational attainment in wealthier nations and reduced smoking rates in Europe and the USA, driven by societal changes and higher costs, have rendered these factors less significant in dementia risk. These trends suggest that broad interventions at the population level could markedly affect the prevalence of dementia risk factors, and governments should consider implementing global educational policies and smoking restrictions to mitigate these risks.
More information: Naaheed Mukadam et al, Changes in prevalence and incidence of dementia and risk factors for dementia: an analysis from cohort studies, The Lancet Public Health. DOI: 10.1016/S2468-2667(24)00120-8
Journal information: The Lancet Public Health Provided by University College London
