Editors' note: Menarche, pregnancies, and breastfeeding do not modify long-term prognosis in multiple sclerosis

Abstract

In the article, “Menarche, pregnancies, and breastfeeding do not modify long-term prognosis in multiple sclerosis,” Zuluaga et al. reported that age at menarche, pregnancy before or after the diagnosis of clinically isolated syndrome (CIS), and breastfeeding did not substantially modify the risk of progressing to clinically definite multiple sclerosis (CDMS) or disability accrual per the Expanded Disability Status Scale (EDSS) in a cohort of 501 female participants with CIS. In response, Drs. Jokubaitis and Dobson argued that the patients with CDMS should be examined separately for the EDSS outcomes because a substantial proportion of the overall cohort did not have a second clinical attack and did not meet either the McDonald 2010 or Barkhof criteria for MS. They seek additional details regarding the propensity score–matched score analysis because a smaller number of matched pairs could limit the generalizability of the results. In addition, they noted that the analyses for the association of pregnancy and breastfeeding on time to EDSS 3.0 were not adjusted for relapse and that the differences between exclusive breastfeeding and mixed feeding strategies merit further exploration in prospective studies. They also argue that the harmful effects of suspending disease-modifying treatments (DMTs) in those with aggressive disease who become pregnant should be considered. Responding to these comments, Drs. Tintore et al. noted that they built the model for time to EDSS 3.0 over the CDMS subcohort, in addition to providing further details of the propensity score–matched analyses. They reported additional analyses for the adjusted hazard ratio for pregnancy (but not for breastfeeding) on considering the annualized relapse rate over the first 3 and 5 years of disease and acknowledged that additional details of breastfeeding were unavailable. Regarding the problem of suspending DMTs in pregnant patients, they noted that they are analyzing a subgroup of women treated with natalizumab or fingolimod. As greater numbers of young women become eligible for DMTs with more inclusive revisions of the McDonald criteria, neurologists are likely to encounter challenging questions about the association of pregnancies and breastfeeding with MS disease activity, and the attendant DMT-related dilemmas, in their practice. In the article, “Menarche, pregnancies, and breastfeeding do not modify long-term prognosis in multiple sclerosis,” Zuluaga et al. reported that age at menarche, pregnancy before or after the diagnosis of clinically isolated syndrome (CIS), and breastfeeding did not substantially modify the risk of progressing to clinically definite multiple sclerosis (CDMS) or disability accrual per the Expanded Disability Status Scale (EDSS) in a cohort of 501 female participants with CIS. In response, Drs. Jokubaitis and Dobson argued that the patients with CDMS should be examined separately for the EDSS outcomes because a substantial proportion of the overall cohort did not have a second clinical attack and did not meet either the McDonald 2010 or Barkhof criteria for MS. They seek additional details regarding the propensity score–matched score analysis because a smaller number of matched pairs could limit the generalizability of the results. In addition, they noted that the analyses for the association of pregnancy and breastfeeding on time to EDSS 3.0 were not adjusted for relapse and that the differences between exclusive breastfeeding and mixed feeding strategies merit further exploration in prospective studies. They also argue that the harmful effects of suspending disease-modifying treatments (DMTs) in those with aggressive disease who become pregnant should be considered. Responding to these comments, Drs. Tintore et al. noted that they built the model for time to EDSS 3.0 over the CDMS subcohort, in addition to providing further details of the propensity score–matched analyses. They reported additional analyses for the adjusted hazard ratio for pregnancy (but not for breastfeeding) on considering the annualized relapse rate over the first 3 and 5 years of disease and acknowledged that additional details of breastfeeding were unavailable. Regarding the problem of suspending DMTs in pregnant patients, they noted that they are analyzing a subgroup of women treated with natalizumab or fingolimod. As greater numbers of young women become eligible for DMTs with more inclusive revisions of the McDonald criteria, neurologists are likely to encounter challenging questions about the association of pregnancies and breastfeeding with MS disease activity, and the attendant DMT-related dilemmas, in their practice.