In a nationally representative sample of English adults aged 65 years and older, those in the lowest wealth quintile had a higher risk for developing dementia compared with those in the highest quintile, regardless of education, index of multiple deprivation and health indicators, according to study findings.
“There are relatively few studies to date that have used socioeconomic indicators other than education to investigate dementia risk,” Dorina Cadar, PhD, of the department of behavioral science and health, University College London, and colleagues wrote in JAMA Psychiatry. “Given that education is typically completed many decades before dementia onset, other individual and area-based components of [socioeconomic status], such as wealth, income, and area deprivation, may provide a more accurate indication of current socioeconomic resources.”
Cadar and colleagues examined dementia incidence in a nationally representative cohort of English older adults to investigate its link with different socioeconomic markers measured at baseline. The measurements — using data from a 12-year follow-up prospective cohort study — included individual-level data, such as education and wealth, as well as group-level data, such as index of multiple deprivation. The investigators also compared the role of socioeconomic markers between two age cohorts: adults born from 1902 to 1925 and from 1926 to 1943.
Of 6,220 English adults aged 65 years and older enrolled in the study, 463 (7.4%) had received a dementia diagnosis in the 12 years between 2002-2003 and 2014-2015. Cadar and colleagues found wealth was a strong indicator of dementia incidence after adjusting for age and sex, but education was not. Analysis showed the risk for developing dementia was almost two times higher for older adults in the lowest wealth quintile compared with those in the highest quintile (HR = 1.68; 95% CI, 1.05-2.86), independent of covariates, education and area-level socioeconomic characteristics.
“Our study confirms that the risk of dementia is reduced among well-off older people compared with those who have fewer economic resources,” Cadar told Healio Psychiatry. “Many factors could be involved. Differences in healthy lifestyle and medical risk factors are relevant. It may also be that better off people have greater social and cultural opportunities that allow them to remain actively engaged with the world.”
Notably, adults in the second-highest quintile of index of multiple deprivation (HR = 1.62; 95% CI, 1.06-2.46) were at higher risk for dementia than those in the lowest (least deprived) quintile.
The overall incidence rate was 11.32 per 1,000 person-years (95% CI, 10.34-12.41 per 1,000-person years). The dementia incidence rate significantly increased with age (incidence rate [IR] = 4.38 in people aged 65 to 69 years; 24.69 in those aged 80 years or older). Furthermore, this difference between the two age groups demonstrated a 30% reduction in the IRs of dementia for the overlapping group of those aged 75 to 79 years born between 1902 and 1925 (IR = 20.29; 95% CI, 16.45-25.28) and those born between 1926 and 1943 (IR = 13.59; 95% CI, 10.33-18.2).
“Public health strategies for dementia prevention should target socioeconomic gaps to reduce health disparities and protect those who are particularly disadvantaged, in addition to addressing vascular risk factors such as hypertension, diabetes mellitus, smoking and heart disease,” Cadar said. – by Savannah Demko
Disclosures: The authors report no relevant financial disclosures.