Incident and Prevalent Peripartum Mental Illness in Mothers with Multiple Sclerosis and Other Chronic Diseases in Sweden.

BACKGROUND:Findings conflict regarding the risk of peripartum mental illness in women with multiple sclerosis (MS) and how this compares to the risk among women with other chronic diseases. We compared the incidence and prevalence of peripartum mental illness among women with MS, epilepsy, inflammatory bowel disease (IBD), diabetes, and women without any of these diseases (comparators). METHODS:Using population-based Swedish administrative health data we selected women with MS, epilepsy, IBD, diabetes, and comparators who had deliveries between 2002 and 2019. Using validated case definitions for peripartum mental illness we estimated the incidence and prevalence of mental illness during the period encompassing pregnancy and the first post-partum year. We compared incidence and prevalence between cohorts using crude estimates and unadjusted Poisson regression. RESULTS:We included 1096,814 women (1936 MS; 7709 epilepsy; 7731 IBD; 7182 diabetes; 1072,256 comparators). Mean (SD) age at conception was 30.1 (5.1) years. Compared to comparators, mothers with MS had a higher incidence of any mental illness (incidence rate ratio [IRR] 1.36; 1.04-1.78), as did mothers with epilepsy (1.78; 1.58-2.00), IBD (1.46; 1.28-1.66) and diabetes (1.61; 1.41-1.83). Mothers with MS, epilepsy, IBD and diabetes also had a higher incidence and prevalence of depression and bipolar disorder than comparators. Mothers with epilepsy had higher incidence rates of anxiety, and higher prevalence ratios of any mental illness and anxiety than mothers with MS. CONCLUSIONS:Women with MS, epilepsy, IBD and diabetes have a similarly elevated incidence and prevalence of peripartum mental illness as compared to mothers without these conditions.