Early Adversity and Socioeconomic Factors in Pediatric Multiple Sclerosis: A Case-Control Study.

Background and objectives: Psychosocial adversity and stress, known to predispose adults to neurodegenerative and inflammatory immune disorders, are widespread among children who experience socioeconomic disadvantage, and the associated neurotoxicity and proinflammatory profile may predispose these children to multiple sclerosis (MS). We sought to determine associations of socioeconomic disadvantage and psychosocial adversity with odds of pediatric-onset MS (POMS), age at POMS onset, and POMS disease activity.

Methods: This case-control study used data collected across 17 sites in the United States by the Environmental and Genetic Risk Factors for Pediatric Multiple Sclerosis Study. Cases (n = 381) were youth aged 3-21 years diagnosed with POMS or a clinically isolated demyelinating syndrome indicating high risk of MS. Frequency-matched controls (n = 611) aged 3-21 years were recruited from the same institutions. Prenatal and postnatal adversity and postnatal socioeconomic factors were assessed using retrospective questionnaires and zip code data. The primary outcome was MS diagnosis. Secondary outcomes were age at onset, relapse rate, and Expanded Disability Status Scale (EDSS). Predictors were maternal education, maternal prenatal stress events, child separation from caregivers during infancy and childhood, parental death during childhood, and childhood neighborhood disadvantage.

Results: MS cases (64% female, mean age 15.4 years, SD 2.8) were demographically similar to controls (60% female, mean age 14.9 years, SD 3.9). Cases were less likely to have a mother with a bachelor's degree or higher (OR 0.42, 95% CI 0.22-0.80, p = 0.009) and were more likely to experience childhood neighborhood disadvantage (OR 1.04 for each additional point on the neighborhood socioeconomic disadvantage score, 95% CI 1.00-1.07; p = 0.025). There were no associations of the socioeconomic variables with age at onset, relapse rate, or EDSS, or of prenatal or postnatal adverse events with risk of POMS, age at onset, relapse rate, or EDSS.

Discussion: Low socioeconomic status at the neighborhood level may increase the risk of POMS while high parental education may be protective against POMS. Although we did not find associations of other evaluated prenatal or postnatal adversities with POMS, future research should explore such associations further by assessing a broader range of stressful childhood experiences.