Background: Multiple sclerosis (MS) is an autoimmune disease with known genetic and environmental susceptibility factors. Breastfeeding has been shown to be protective in other autoimmune diseases.
Objective: This case-control study analyzed the association of breastfeeding in infancy on the risk of developing MS.
Methods: A case-control study was performed in Berlin of 245 MS patients and 296 population-based controls, who completed a standardized questionnaire on their history and duration of breastfeeding in infancy and demographic characteristics. Univariable and multivariable logistic regression analysis was performed to investigate the association between breastfeeding and MS. The multivariate model was adjusted for age, gender, number of older siblings, number of inhabitants in place of domicile between ages 0 and 6 (categorized in each case), and daycare attendance between ages 0 and 3.
Results: In multivariable analysis, breastfeeding showed an independent association with MS (adjusted OR 0.58; p = 0.028). However, with no breastfeeding as reference, the protective effect only emerges after four months of breastfeeding (multivariable analysis for ≤ four months adjusted OR 0.87; p = 0.614 and for > four months OR 0.51; p = 0.016).
Conclusion: The results of this case-control study support the hypothesis that breastfeeding is associated with a lower risk of MS. These results are in line with findings of previous studies on other autoimmune diseases, in which breastfeeding was shown to have protective effects.