Association between becoming a carer in later life and changes in the trajectory of cognitive function: results from the English longitudinal study of ageing.

The influence of becoming a carer on cognitive function presents a complex picture. Variations in intensity, recipients and locations of caring may influence cognition differently. Using waves 2 to 10 (2004/2005 to 2021/2023) of the English Longitudinal Study of Ageing, we examined cognitive changes before and after transitioning into caring and explored whether these effects depend on care characteristics. We integrated the strengths of both 'matching' and 'before and after' methods. Using propensity score matching, we paired 2765 carers aged 50+ with 2765 non-carers. Using piecewise growth curve modelling, we modelled the changes in cognitive trajectories-memory and executive function-before and after transitioning into caring. Analyses also examined variations by care hours, location, recipient, number of people caring for, duration, sex and wealth. Carers were on average 60 years old, and 56% were women. We found that transition into lower-intensity caring responsibilities (5-9 hours/week), caring outside the household and caring for parents/parents-in-law exhibited a slower decline in executive function than non-carers. Those providing very intensive care (50+ hours/week), caring within the household or caring for a spouse/partner showed a more rapid decline. Memory changes followed a similar but much weaker pattern than for executive function. No evidence was found that sex or wealth moderated these effects. This suggests that the influence of caring on cognitive function is likely to be shaped by care-related characteristics. Our findings underscore the importance of preventing carer overload. While caring may help preserve cognitive function, excessive caring demands appear to accelerate cognitive decline.