Alzheimer's disease is often discussed through the lens of the patient, but the invisible workforce sustaining that care — overwhelmingly female — absorbs enormous personal and economic costs that are rarely measured with multinational precision. That data gap matters because policy and support systems built on single-country estimates may systematically underestimate how gender shapes the caregiving experience across different healthcare and cultural contexts.
This large cross-sectional study harmonized baseline data from four cohort studies spanning seven countries — France, Germany, the United Kingdom, Italy, Spain, Japan, and the United States — encompassing community-dwelling individuals with clinically diagnosed Alzheimer's disease and their informal caregivers. Monthly informal care costs were calculated using the Resource Utilization in Dementia Questionnaire, converting caregiver time and lost productivity into US dollar equivalents. Psychological burden was measured via the Zarit Burden Interview, a validated 88-point scale. Two-part econometric models (logistic followed by gamma regression) were used for cost differences, while linear regression addressed burden scores — all adjusted for relevant covariates. Across this multinational sample, female caregivers consistently faced higher burden scores and greater nonmedical societal costs compared to male caregivers, a pattern that held across markedly different health systems and cultural norms.
This finding carries real weight because it replicates across jurisdictions with vastly different welfare structures, suggesting the gender gap in caregiving burden is not a policy artifact but a durable social phenomenon. The cross-sectional design limits causal inference, and harmonizing data across cohorts always introduces measurement heterogeneity. Nevertheless, the multinational scope substantially strengthens external validity compared to prior single-country work. For health-conscious adults — particularly women in midlife who statistically occupy the highest-risk caregiving years — the study reinforces that caregiver health is not collateral damage but a measurable, quantifiable outcome deserving its own clinical attention. The finding should be considered incremental in confirming what smaller studies suggested, but the scale and geographic breadth elevate it meaningfully above prior evidence.