Alzheimer’s and cognitive decline: if wages are low in youth, the risk increases in adulthood

There is a common thread linking financial resources in youth and adulthood to the risk of cognitive decline and Alzheimer’s disease. This association should also prompt reflection in terms of policy-making, not only in the social context of reducing the proportion of young NEETs (young people aged between 15 and 29 who are not in education, employment or training – in Italia the figure stands at around 15.2 per cent of the total), but above all to promote an average increase in incomes. This is because accumulating financial difficulties over time, both in youth and adulthood, would lead to a greater risk of developing chronic neurological conditions that are bound to have an impact on healthcare budgets.

This study, which sheds light on the complex interplay between economics and neuroscience – going well beyond potential confounding factors such as cognitive abilities in childhood, level of education and socio-economic disadvantage in childhood, is an original study published in Innovation in Aging and conducted by experts at University College London, led by Praveetha Patalay (corresponding author Jacques Wels). “Health, in line with Grossman’s 1972 model, can therefore be viewed as a stock of capital that depreciates over time and requires continuous investment (care, medication, prevention, nutrition, physical activity) to preserve, as far as possible, its value – notes Marcello Montefiori, Professor of Economics at the University of Genoa -. Prolonged financial stress can accelerate the deterioration of well-being and, at the same time, reduce the ability to sustain the investments needed to counteract it”.

The study analysed data from 2,759 people in the UK, drawn from questionnaires collected as part of the MRC National Survey of Health and Development, a British cohort study. Study participants were asked about their household income at three different points in time: at the ages of 26, 43 and 53. They were classified as having a persistently low income if they were in the lowest 20 per cent of the group on at least two occasions, which was the case for around one in six participants. Financial difficulties were assessed using targeted questions: for example, participants were asked whether they found it difficult to manage their finances with their disposable income, or whether they had experienced problems paying their utility bills. Participants were classified as experiencing financial difficulties if they scored above a certain threshold on the questionnaire at least twice between the ages of 36 and 53, which occurred in around one in eight people. Finally, the cognitive tests assessed verbal memory and processing speed. In addition, magnetic resonance imaging (MRI) scans were carried out on a subset of the study population, enabling the assessment of factors such as cerebral atrophy (reduction in brain volume) and ventricular enlargement – that is, the enlargement of the fluid-filled cavities in the brain – which is an indicator.

The British cohort study clearly shows that those who experienced persistent financial hardship or a persistently low income during early and middle adulthood performed worse in the first cognitive tests taken shortly after turning 50 (at the age of 53, to be precise). But that is not all. MRI scans revealed that those who had suffered from limited financial resources exhibited poorer brain health, with a higher incidence of brain atrophy among those aged between 69 and 71. All of this, as mentioned, was found even after controlling for educational attainment and any social or cognitive deficits in childhood. Among the interesting findings to emerge from the analysis was also a gender difference. The link between financial hardship and poorer brain health in later life was found to be particularly strong among men, particularly those who had experienced specific difficulties in childhood and who carried a specific genetic variant associated with an increased risk of Alzheimer’s (APOE-ε4). To explain the gender differences, experts point to the greater prevalence of harmful lifestyle habits such as smoking and alcohol abuse among men, as well as higher levels of stress caused by financial difficulties, bearing in mind that for those born in 1946, the male member of the household was the main breadwinner.

According to the study, there may be various mechanisms that highlight the ‘common thread’ between economic status over the years and brain health. More pronounced cognitive ageing could be linked to inflammation – a factor associated with chronic stress and known to accelerate brain decline – as well as to worries: constantly worrying about one’s financial situation could lead to an increase in ‘cognitive load’, resulting in reduced concentration, which over time tends to diminish one’s ability to focus on other tasks. But regardless of the hypotheses, there is one fact that makes this research particularly interesting: it assesses the association over time, rather than as a ‘one-off’ event. “Our study, which uses data collected over several decades, allows us to observe that it is the accumulation of difficulties over many years that is linked to poorer outcomes in terms of cognitive health, rather than occasional episodes of adversity,” notes the expert in a statement from the London university –”. But take note: the researchers themselves point out that, from a policy perspective, safeguarding economic prospects and tackling chronic poverty can really make a difference to health. Tackling inequality therefore becomes a commitment. “Preventing economic hardship from becoming chronic can be seen as a genuine investment in health,” concludes Montefiori. Translating this principle into public policy is, however, complicated by a clear time lag: the costs are immediate, whilst the benefits – which are, moreover, difficult to measure – may only become apparent years later.”