Nationwide population-based cohort study of psychiatric disorders in individuals with Ehlers-Danlos syndrome or hypermobility syndrome and their siblings

Background: To assess the risk of psychiatric disorders in Ehlers-Danlos syndrome (EDS) and hypermobility syndrome. Methods: Nationwide population-based matched cohort study. EDS, hypermobility syndrome and psychiatric disorders were identified through Swedish national registries. Individuals with EDS (n = 1,771) were matched with comparison individuals (n = 17,710). Further, siblings to individuals with EDS who did not have an EDS diagnosis themselves were compared with matched comparison siblings. Using conditional logistic regression, risk of autism spectrum disorder (ASD), bipolar disorder, attention deficit hyperactivity disorder (ADHD), depression, attempted suicide, suicide and schizophrenia were estimated. The same analyses were conducted in individuals with hypermobility syndrome (n = 10,019) and their siblings. Results: EDS was associated with ASD: risk ratio (RR) 7.4, 95 % confidence interval (95 % CI) 5.2-10.7; bipolar disorder: RR 2.7, CI 1.5-4.7; ADHD: RR 5.6, CI 4.2-7.4; depression: RR 3.4, 95 % CI 2.9-4.1; and attempted suicide: RR 2.1, 95 % CI 1.7-2.7, but not with suicide or schizophrenia. EDS siblings were at increased risk of ADHD: RR 2.1, 95 % CI 1.4-3.3; depression: RR 1.5, 95 % CI 1.1-1.8; and suicide attempt: RR 1.8, 95 % CI 1.4-2.3. Similar results were observed for individuals with hypermobility syndrome and their siblings. Conclusions: Individuals with EDS and hypermobility syndrome are at increased risks of being diagnosed with psychiatric disorders. These risk increases may have a genetic and/or early environmental background as suggested by evidence showing that siblings to patients have elevated risks of certain psychiatric disorders.