Comment on “Dementia prevention, intervention, and care: 2024 report of the Lancet Standing Commission”

Dear Editor, with great interest we read the paper titled “Dementia Prevention, Intervention, and Care: 2024 Report of the Lancet Standing Commission.”[1] Lancet Dementia prevention, intervention, and care series began in July 2017, initially, there were nine modifiable risk factors that were identified including lower education, hearing impairment, decreased exercise and physical activity, diabetes, hypertension, obesity, smoking, depression, and social isolation. July 2020 Lancet Commission added three more additional factors such as excessive alcohol consumption, traumatic brain injury, and air pollution. Currently 2024 Lancet Commission added the new compelling evidence that untreated vision loss and high low-density lipoprotein (LDL) cholesterol as newer risk factors. The Lancet 2024 report is a valuable and comprehensive resource. The authors analyzed data from major global databases such as the UK Biobank, Swedish, Danish, and HUNT studies which gives a foundation for understanding dementia and its modifiable risk factors. According to the findings, modifiable risk factors can prevent 45% of dementia. It demonstrated that population-based research, particularly in low- and middle-income countries (LMICs) and among minority ethnic groups is essential for addressing disparities in dementia prevention and care. Untreated vision loss and high LDL cholesterol are two new modifiable risk factors that were identified to contribute to 2% and 7% of dementia prevalence, respectively. The report also highlights the meta-analysis on hearing loss and depression for modifiable interventions and provides recommendations for managing dementia, particularly in neuropsychiatric symptoms and caregiver support. Including 14 modifiable and probable risk factors is likely toward comprehensive prevention. Despite these strengths, certain aspects of the study require further attention. Not all risk factors are explained from a neuropathological or diagnostic perspective, making it difficult to fully understand the biological mechanisms behind them, which is critical for developing effective interventions. More data comes from high-income countries (HICs), limiting its validity to LMICs, where risk factors and health outcomes may differ. For example, the report primarily focuses on Mediterranean and DASH diets without studying other dietary patterns that might affect dementia rates in LMIC populations.[2] Another concern is the age group for population attributable fraction (PAF) calculations. The calculation in the report assumes that modifying one risk factor does not influence others, ignoring potential interactions and synergistic effects between risk factors. This could lead to an overestimation of the combined PAF. In addition, while the report addresses individual cardiometabolic factors such as hypertension and diabetes, it does not consider metabolic syndrome as a unified cluster of interrelated conditions. Metabolic syndrome has been independently associated with an elevated risk of dementia, and its exclusion overlooks a significant and modifiable risk factor that could enhance comprehensive prevention strategies.[3] The report focuses on individuals who are aged 45 years and older while calculating PAF, although the HUNT study from which the data were derived was a longitudinal study of adults more than 20 years of age,[4] even though evidence suggests that people as young as 18 years of age could be at risk. Including younger people is crucial, as earlier interventions could prevent or delay the onset of dementia. Regarding hormone replacement therapy, the report focuses only on studies showing a negative association but lacks the balanced view.[5] The report only covers 45% of dementia risk factors, leaving 55% of a significant portion unexplored. While stroke, atrial fibrillation, Parkinson’s disease, and HIV are acknowledged as causative agents for dementia, the report did not discuss the impact of other significant medical conditions that may also contribute to dementia risk. Conditions such as myocardial infarction, strokes, brain infections, chronic kidney disease, and respiratory diseases, although not traditionally indicated, could play a critical role in increasing dementia susceptibility.[6] Studying these disease conditions which could have been contributed by primary cardiometabolic and vascular risk factors could offer a more complete understanding of the broader way of health conditions that influence dementia onset and progression. The report discusses air pollution but neglects other environmental and occupational factors such as exposure to heavy metals, pesticides, and solvents have been linked to cognitive decline.[7] Future reports should address gathering more evidence to determine potential modifiable risk factors, such as diet and sleep, to understand their role in preventing dementia. It is crucial to add more data from LMICs to ensure global relevance, as health challenges and risk profiles in these regions often differ from HICs. Future research should also include younger cohorts, particularly those aged 18–65 since there is growing evidence that dementia risk factors may develop earlier in life.[8] This could lead to earlier interventions and more effective prevention strategies. The role of traditional practices should also be explored, as these practices may offer unique protective benefits against dementia that are often overlooked in modern medical research.[9] With the increase in digital health tools, the commission should study how mobile apps, wearables, and telemedicine can help in the prevention and management of dementia. Digital technology has the potential to reshape early diagnosis, monitoring, and personalized care, offering new ways to support the individuals at risk of or people living with dementia.[10] The 2024 Lancet Commission provides important insights into dementia prevention, but there are areas to build on. Future Lancet reports should focus on including data from younger populations, exploring traditional practices, and gathering more data from LMICs to ensure a good understanding. Looking into the potential of digital health tools and confirming risk factors such as diet and sleep could also enhance global prevention efforts. While individual and community-level interventions have been discussed, there is no mention of systemic barriers within healthcare like inadequate healthcare infrastructure, or workforce shortage which could limit effective intervention delivery for preventing dementia. By addressing these policy aspects, future research can offer even stronger strategies for preventing dementia. Sincerely, Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.