In England and Canada, wealth appears to shape not only how well people age, but also how quickly they lose essential physical abilities. A comparative study published in PLOS Medicine reports that adults with fewer financial resources generally began later life with poorer physical function and experienced steeper declines in mobility, strength, lung capacity, and independence. The differences were especially pronounced in England, where the least wealthy 60-year-olds had walking speeds comparable to those of the wealthiest 75-year-olds. The findings suggest that socioeconomic inequality can be understood as a measurable difference in functional ageing—one that may separate groups by more than a decade of apparent biological and physical capability.
The study was led by researchers from Geneva University Hospitals and involved data from two major longitudinal cohorts: 8,511 participants in the English Longitudinal Study of Ageing, or ELSA, and 22,605 participants in the Canadian Longitudinal Study on Aging, or CLSA. All participants were between 50 and 85 years old. Rather than examining health at a single point in time, the researchers analyzed repeated measurements collected over several years to estimate how physical abilities changed as participants aged. This longitudinal design allowed the team to distinguish between having a lower level of function and experiencing a faster decline, two processes that are often combined in conventional health comparisons.
Researchers evaluated several indicators of physical capability. Walking speed provided a measure of mobility and overall neuromuscular performance, while grip strength served as an established marker of muscle function, frailty risk, and future disability. Lung function was assessed using forced expiratory volume, or FEV, which reflects how much air a person can forcefully exhale in a specified period. The analysis also considered hearing and self-reported difficulty with everyday activities such as dressing, bathing, and eating. These tasks are important because they capture the practical consequences of ageing: whether people can remain independent, move safely through their environment, and manage basic routines without assistance.
To model the trajectories, the investigators used mixed-effects statistical models. These models can account for repeated observations from the same individual while also estimating average patterns across an entire population. The researchers included age, age squared, and birth year to represent both the gradual and potentially nonlinear nature of ageing. Sex, race, height, wealth, and the interaction between wealth and age were also incorporated. The wealth-by-age interaction was particularly important because it tested whether socioeconomic position was associated not merely with different starting points, but with different rates of decline. Additional analyses adjusted for chronic diseases, body weight, and health-related behaviors including smoking, allowing the researchers to determine whether these factors fully explained the observed inequalities.
They did not. Across both countries, people with less wealth tended to show lower physical function and larger losses over time. The pattern was most apparent for walking speed and the ability to perform daily activities, suggesting that financial disadvantage may accumulate into a growing loss of physical independence. The wealth gradient was also visible in grip strength and lung function, although the size and direction of some associations varied by sex and country. Because the study was observational, it cannot establish that low wealth directly causes faster ageing. Wealth may influence housing, nutrition, working conditions, neighborhood safety, healthcare access, stress exposure, and opportunities for physical activity, while early-life circumstances and unmeasured health factors may influence both wealth and later function.
The contrast between England and Canada was one of the study’s most striking findings. Although both countries provide universal healthcare and have broadly comparable levels of income inequality, the gaps associated with wealth were consistently larger in England for several measures of functional ageing. For walking speed, the researchers estimated an apparent age difference of roughly 15 years between the least and most wealthy groups in England, compared with approximately nine years in Canada. These estimates do not mean that a person’s chronological age has changed, or that every individual in a wealth group follows the same trajectory. Instead, they compare predicted levels of function across socioeconomic groups and express the difference in terms of the age at which similar performance is typically observed.
The researchers also identified important differences between women and men. Among the least wealthy participants, women experienced greater difficulties with mobility and daily activities than men in the same socioeconomic group. At the same time, women in this group showed better lung function than their male counterparts. This divergence illustrates why broad measures of disadvantage can conceal meaningful differences within populations. Physical function is shaped by the interaction of sex, occupational history, health behaviors, disease patterns, social roles, and exposure to economic hardship. The authors describe their approach as intersectional because it examines how these dimensions combine rather than treating all disadvantaged adults as a single, uniform category.
The findings carry implications for public health policy because functional decline is closely connected to falls, disability, institutional care, social isolation, and healthcare use. Interventions that begin only after severe disability appears may miss the period when differences are still modifiable. Policies supporting secure housing, adequate income, nutritious food, safer neighborhoods, accessible transportation, preventive healthcare, and opportunities for lifelong physical activity could help reduce the conditions that accelerate loss of function. The results also suggest that universal healthcare alone may not eliminate health inequalities. Medical treatment is only one influence on ageing; the social and physical environments in which people live may determine whether they can maintain strength, mobility, and independence over decades.
Silvia Stringhini, the study’s senior author, said the larger wealth gaps observed in England were unexpected and that the comparison could not yet explain why the two countries diverged. Stephanie Schrempft, the first author, emphasized that lower wealth was associated not simply with worse health at a given age, but with losing physical independence more rapidly. The authors caution that their analysis could not fully account for childhood conditions or access to private healthcare, and that the results should not be interpreted as proof of a direct causal pathway from wealth to ageing. Further cross-country research is now planned to investigate which structural factors may be responsible for the different trajectories.
The study offers a measurable way to understand socioeconomic inequality as a time-related process. Two people who are the same chronological age may have very different levels of mobility, strength, respiratory capacity, and ability to manage daily life, and those differences can widen as they grow older. By tracking these changes in large populations, researchers can move beyond the question of who is healthier at one moment and ask how social conditions influence the pace of functional ageing. The evidence from England and Canada indicates that reducing inequality will require more than encouraging individual lifestyle changes. It will also require structural policies aimed at preventing disadvantage from becoming a faster loss of physical capability and independence.
Subject of Research: People
Article Title: Socioeconomic inequalities in functional ageing trajectories in England and Canada: A comparative longitudinal cohort study
News Publication Date: August 13, 2026
Web References: https://plos.io/4wbNOyC; https://doi.org/10.1371/journal.pmed.1004833
References: Schrempft S, Vereecke S, Nehme M, Schmidt KL, Guessous I, Kobor MS, et al. (2026). “Socioeconomic inequalities in functional ageing trajectories in England and Canada: A comparative longitudinal cohort study.” PLOS Medicine 23(8): e1004833.
Image Credits: Schrempft S, et al., 2026, PLOS Medicine, CC BY 4.0
Keywords: ageing, healthy ageing, socioeconomic inequality, wealth, physical function, mobility, walking speed, grip strength, lung function, disability, England, Canada, longitudinal study, public health, PLOS Medicine
