Abstract
The aim of the present study was to describe the effect of an individual's mental health disorder on the resources of his or her adult siblings. A subject rarely analyzed on a large scale. The French National Health Data System (SNDS) collects data on individuals, including their characteristics and the types of healthcare used. A national observational sectional case-control study included individuals covered as of 1 January 2019 and receiving yearly at least one healthcare reimbursement in 2019 including their SNDS data collected from 2013 to 2018. The main variables of interest were a Complementary Universal Health Coverage (CUHC) granted to people who had limited resources. There is also a long-term disease (LTD) status qualifying also for 100% for a specific disease and an ecological index of social deprivation of the place of residence. Conditions were also collected using a specific tool including LTD and hospital diagnosis. Analyzed siblings included 280 709 cases with at least one member suffering from a mental health disorder and 561 418 randomly selected control individuals were addressed using a multilevel model. Siblings of people with mental health problems were more likely to benefit from CUHC or to live in the most deprived area. In addition, the study also highlighted the importance of parental background, which appears to be poorer than in the control population. Social inequalities are particularly marked among the siblings of a person suffering from mental health disorder. Further studies are needed to better understand and enlarge these observational results.