Background Brain disorders, including neurological conditions and mental disorders, pose a considerable economic burden in Denmark. However, the costs of illness are not limited to the patients themselves, as the consequences of living with a brain disorder may also impact close relatives.

Aim We aimed to assess excess societal costs related to healthcare utilization and income loss for the closest family relatives of patients with brain disorders.

Methods This population-based cohort study included the closest family relatives of patients with prevalent (by Jan 1, 2021) or incident (during 2016-2021) brain disorders. They were compared with corresponding relatives of matched population comparisons. Patients were categorized into three age strata: children and young people (0-24 years), adults (25-64 years), and older adults (65+ years). We specified criteria for identifying the closest family relative for each age stratum. Using data from national registries, we estimated attributable healthcare costs, and for working-age relatives (18-65 years), we also estimated income loss.

Results In 2021, close relatives of patients with brain disorders included 125,495 fathers and 96,154 mothers of children and young people, 880,661 relatives of adults, and 378,826 relatives of older adults. The pooled attributable costs of brain disorders incurred by closest family relatives were 2,407 million EUR for prevalent disease in 2021 and 794 million EUR for incident disease the first year following incidence. The dominating cost component was income loss for working-age relatives.

Conclusion The higher healthcare costs and especially the lower income for relatives of patients with brain disorders adds to the societal economic burden of brain disorders in Denmark. Informal care provided by relatives may contribute to this, underscoring the need to consider their caregiving burden in questions of healthcare prioritization.

The authors have declared no competing interest.

This work was funded by the Lundbeck Foundation (grant number: R433-2023-1140).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

According to Danish law, non-interventional registry-based studies do not require informed consent or approval by a research ethics committee. The study was registered at Aarhus University (j. no. 2016-051-000001/603).

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The data underlying the results are from the specified Danish registries, and not publicly available. Researchers who fulfil the requirements set by the data providers (Statistics Denmark and the Danish Health Data Authority) can obtain similar data.