A recent study led by researchers from University College London (UCL) has found that socioeconomic factors, including education, occupation, and wealth, significantly affect the likelihood of developing cognitive impairment or dementia in later life and the prospects of recovery. The study in Scientific Reports followed 8,442 adults 50 across England from 2008/09 to 2018/19. The primary objective was to explore how socioeconomic conditions at the study’s outset correlated with changes in cognitive status over a decade.
The longitudinal analysis monitored participants’ transitions between various cognitive states: healthy, mild cognitive impairment, and dementia. Additionally, it investigated the occurrences of cognitive improvement, where individuals regained a healthy state from mild cognitive impairment. Socioeconomic information was gathered through self-administered questionnaires, while cognitive impairment was assessed through a combination of doctor’s diagnoses, cognitive test results, and participant-reported symptoms, thus providing a holistic view of each individual’s cognitive health. The study also took demographic variables, such as age, gender, and marital status, into account.
By quantifying the duration participants spent in each cognitive state and their transitions to neurocognitive disorders, the research team could extensively understand the impact of socioeconomic factors on both the progression and the duration of cognitive states over time. The findings revealed that individuals from more socioeconomically privileged backgrounds—those with higher education beyond secondary school, those holding managerial or professional jobs, and those within the wealthiest third of the population — had a lower risk of progressing from a healthy cognitive state to mild cognitive impairment or from mild cognitive impairment to dementia compared to their less privileged counterparts.
Specifically, the study showed that post-secondary education decreased the risk of transitioning from a healthy cognitive state to mild cognitive impairment by 43%. Similarly, being within the wealthiest third reduced the progression from mild cognitive impairment to dementia by 26%. Furthermore, these socioeconomically advantaged groups were more likely to experience recovery from mild cognitive impairment, with wealthy individuals being 56% more likely and those with post-secondary education or engaged in non-manual occupations being 81% more likely to revert to a healthy cognitive state compared to those less privileged.
Dr Dorina Cadar, the senior author from the UCL Department of Behavioural Science and Health and Brighton and Sussex Medical School, emphasised the vital role of wealth, education, and occupation not just in reducing the risk of deterioration from mild cognitive impairment to dementia, but also in enhancing the chances of reversing cognitive impairment. This recovery is pivotal for improving the quality of life in the elderly and reducing the long-term impact of mental disorders on healthcare systems, families, and society.
The researchers suggest that the protective effects of higher socioeconomic status might be attributed to several factors. Higher education and intellectually demanding jobs likely provide greater mental stimulation, which helps build a robust cognitive reserve that shields against impairment and dementia. Additionally, people with higher educational attainment, more demanding jobs, and more incredible wealth generally have better access to healthcare services and health-promoting resources such as nutritious diets, physical activity, and preventive care, which support cognitive health. These resources also facilitate stabilising or improving mental functions, particularly when impairment is identified early.
While the study does not conclusively explain why certain socioeconomic factors influence cognitive health, the authors, including lead author and PhD candidate Aswathikutty Gireesh from UCL Epidemiology & Health Care, believe that access to cognitive health-supporting resources plays a crucial role. They hope their findings will pave the way for further investigations into how wealth and other socioeconomic factors shield against the early onset of cognitive impairment, ultimately informing social policies that promote mental and cognitive well-being across all socioeconomic strata.
More information: Aswathikutty Gireesh et al, Socioeconomic inequalities linked to the transitioning to neurocognitive disorders and mortality, Scientific Reports. DOI: 10.1038/s41598-024-74125-w
Journal information: Scientific Reports Provided by University College London
