Sex and Socioeconomic Disparities in Dementia Risk: A Population-Attributable Fraction Analysis in Argentina

Preventing dementia in Italy: Estimations of modifiable risk factors and public health implications

BACKGROUND

Dementia is a major global public health challenge, with over 50 million cases in 2020, projected to reach 152 million by 2050. Effective prevention strategies are needed to reduce the impact of modifiable risk factors associated with dementia, particularly in countries with ageing populations like Italy. The Population Attributable Fraction (PAF) and Potential Impact Fraction (PIF) are key metrics for understanding and reducing dementia cases through targeted interventions.

OBJECTIVES

This study aimed to revise and expand PAF estimates for dementia in Italy, integrate them with PIF calculations, and assess the alignment of regional health policies with these risk factors. Additionally, the study explored regional variations in PAFs and evaluated the potential for reducing dementia incidence through feasible public health interventions.

DESIGN

A cross-sectional analysis was conducted using data from two national public health surveillance systems, PASSI and PASSI d'Argento (PdA), to estimate PAFs and PIFs for dementia at both national and regional levels. The study used data collected between 2017 and 2019.

SETTING

Data were drawn from 19 Italian regions and two autonomous provinces, providing national and subnational estimates of modifiable risk factors for dementia.

PARTICIPANTS

The study population included a nationally representative sample of 86,494 individuals aged 18-64 (PASSI) and 48,516 individuals aged 65 and older (PdA).

MEASUREMENTS

PAFs were calculated for 11 of the 12 modifiable risk factors identified by the Lancet Commission in 2021, with data from the PASSI and PdA systems. PIFs were calculated to estimate the potential reduction in dementia cases under different intervention scenarios. Regional variations in PAFs were assessed and aligned with health policies outlined in the Regional Prevention Plans.

RESULTS

The national combined PAF for 11 modifiable risk factors was 39.6 % (95 % CI: 20.8-55.9). Midlife hypertension and physical inactivity were the most significant contributors, accounting for 12.3 % of the total PAF. Cardiovascular risk factors collectively explained over 50 % of preventable dementia cases. Regional PAFs ranged from 31.7 % to 47.5 %, with a clear north-south gradient; southern regions exhibited higher PAFs due to cardiovascular factors. Despite broad consistency between national and regional PAFs, significant variability was found in how regions addressed risk factors, particularly air pollution. At the national level, a 10 % reduction in risk factors would prevent 54,495 dementia cases, with subnational PIFs ranging from 3.7 % to 6.0 %.

CONCLUSIONS

This study highlights the substantial potential for dementia prevention in Italy through targeted public health interventions. However, significant regional disparities in PAFs and the alignment of health policies underscore the need for a more nuanced, regionally tailored approach. Future strategies should integrate both PAF and PIF to maximize the impact of interventions, particularly in addressing cardiovascular risk factors. These findings can guide the development of evidence-based policies to reduce dementia incidence across Italy.

Next generation brain health: transforming global research and public health to promote prevention of dementia and reduce its risk in young adult populations

Efforts to prevent dementia can benefit from precision interventions delivered to the right population at the right time; that is, when the potential to reduce risk is the highest. Young adults (aged 18-39 years) are a neglected population in dementia research and policy making despite being highly exposed to several known modifiable risk factors. The risk and protective factors that have the biggest effect on dementia outcomes in young adulthood, and how these associations differ across regions and groups, still remain unclear. To address these uncertainties, the Next Generation Brain Health team convened a multidisciplinary expert group representing 15 nations across six continents. We identified several high-priority modifiable factors in young adulthood and devised five key recommendations for promoting brain health, ranging from individual to policy levels. Increasing research and policy focus on brain health across the life course, inclusive of younger populations, is the next crucial step in the efforts to prevent dementia at the global level.

Differences in cognitive function at 18 y of age explain the association between low education and early dementia risk

Major initiatives attempt to prevent dementia by targeting modifiable risk factors. Low education is frequently pointed to, due to its relationship with dementia. Impact of education is difficult to assess, however, because of associations with multiple other factors, requiring large population-representative samples to tease the relationships apart. We studied 207,814 Norwegian men born between 1950 and 1959 who underwent compulsory cognitive testing during military conscription as young adults, to systematically test associations of education, cognition, and other important factors. Participants were grouped into five education levels and seven cognitive levels. A total of 1,521 were diagnosed with dementia between ages 60 and 69 y. While having compulsory education only was associated with increased risk (Hazard ratio [HR] = 1.37, CI: 1.17 to 1.60), this association was markedly attenuated when controlling for cognitive test scores (HR = 1.08, CI: 0.91 to 1.28). In contrast, low cognitive score was associated with double risk of later diagnosis, even when controlling for education (HR = 2.00, CI: 1.65 to 2.42). This relationship survived controlling for early-life socioeconomic status and replicated within pairs of brothers. This suggests that genetic and environmental factors shared within families, e.g., common genetics, parental education, socioeconomic status, or other shared experiences, cannot account for the association. Rather, independent, nonfamilial factors are more important. In contrast, within-family factors accounted for the relationship between low education and diagnosis risk. In conclusion, implementing measures to increase cognitive function in childhood and adolescence appears to be a more promising strategy for reducing dementia burden.

Vascular cognitive impairment and dementia: a narrative review

Vascular cognitive impairment (VCI) is the second most common cause of cognitive impairment after Alzheimer's disease. The VCI spectrum involves a decline in cognition attributable to vascular pathologies (e.g., large infarcts or hemorrhages, microinfarcts, microbleeds, lacunar infarcts, white matter hyperintensities, and perivascular space dilation). Pathophysiological mechanisms include direct tissue injury, small vessel disease, inflammaging (inflammation + aging), atrophy, and altered neurotransmission. VCI is diagnosed using distinct clinical and radiological criteria. It may lead to long-term disability and reduced quality of life. An essential factor for reducing cognitive impairment incidence is preventing stroke by managing traditional and non-traditional cerebrovascular risk factors. This article reviews the spectrum of VCI, epidemiology, risk factors, pathophysiology, diagnosis, available treatment, and preventive strategies.