Risk factors of early onset of MS in women in reproductive age period: survival analysis approach

The role of sex and pregnancy in multiple sclerosis: what do we know and what should we do?

INTRODUCTION

Multiple sclerosis (MS) is more prevalent in women than in men. The sex of the patient, and pregnancy, are reported to be associated with the clinical features of MS. The mechanism of this is unclear.

AREAS COVERED

This review summarizes data about sex differences in MS and the role of pregnancy. Possible mechanisms for the effects of sex and pregnancy are summarized, and practical suggestions for addressing these issues are provided.

EXPERT OPINION

There is considerable interdependence of the variables that are associated with MS. Men have a worse outcome of MS, and this could be due to the same factors that lead to greater incidence of neurodegenerative disease in men. The possible role of parity on the long-term outcome of MS is of interest. Future studies that look at the mechanisms of the effects of the sex of the patient on the outcome of MS are required. However, there are some actions that can be taken without further research. We can concentrate on public health measures that address the modifiable risk factors for MS and ensure that disease is controlled in women who intend to become pregnant and use appropriate disease modifying agents during pregnancy.

Association of Pregnancy With the Onset of Clinically Isolated Syndrome

Importance

Multiple sclerosis (MS) is usually diagnosed in women during their childbearing years. Currently, no consensus exists on whether pregnancy can delay the first episode of demyelination or clinically isolated syndrome (CIS).

Objective

To investigate the association of pregnancy with time to CIS onset.

Design, Setting, and Participants

This multicenter cohort study collected reproductive history (duration of each pregnancy, date of delivery, length of breastfeeding) on all participants between September 1, 2016, and June 25, 2019. Adult women being treated at the MS outpatient clinics of 4 tertiary hospitals in 2 countries (Charles University and General University Hospital in Prague, Czech Republic; Royal Melbourne Hospital in Melbourne, Australia; Alfred Hospital in Melbourne, Australia; and John Hunter Hospital in Newcastle, Australia) were recruited to participate in the study. Preexisting data (date of CIS onset, date of birth, sex, date of clinical onset, and Expanded Disability Status Scale result) were collected from MSBase, an international registry of long-term prospectively collected data on patients with MS. Data analyses were performed from June 1, 2019, to February 3, 2020.

Exposures

Gravida (defined as any pregnancy, including pregnancy that ended in miscarriage and induced abortion) and parity (defined as childbirth after gestational age of more than 20 weeks, including livebirth and stillbirth) before CIS onset.

Main Outcomes and Measures

Time to CIS onset. The following were assessed: (1) whether women with previous pregnancies and childbirths had a delayed onset of CIS compared with those who had never been pregnant and those who had never given birth, and (2) whether a dose response existed, whereby a higher number of gravidity and parity was associated with a later onset of CIS.

Results

Of the 2557 women included in the study, the mean (SD) age at CIS onset was 31.5 (9.7) years. Of these women, before CIS onset, 1188 (46%) had at least 1 pregnancy and 1100 (43%) had at least 1 childbirth. The mean (SD) age at first pregnancy was 23.3 (4.5) years and at first childbirth was 23.8 (4.5) years. Women with previous pregnancies and childbirths had a later onset of CIS compared with those who had never been pregnant (HR, 0.68; 95% CI, 0.62-0.75; P < .001), with a median delay of 3.3 (95% CI, 2.5-4.1) years. Women who had given birth also had a later CIS onset compared with women who had never given birth (HR 0.68; 95% CI, 0.61-0.75; P < .001), with a similar median delay of 3.4 (95% CI, 1.6-5.2) years. A higher gravidity and parity number was not associated with delay in CIS onset.

Conclusions and Relevance

This study suggests an association between previous pregnancies and childbirths and timing of CIS onset, but having more pregnancies or childbirths did not appear to be associated with a later CIS onset. Further studies are needed to help explain the mechanisms behind the associations between pregnancy and onset of multiple sclerosis.

Pregnancy and multiple sclerosis: Clinical effects across the lifespan

Multiple sclerosis (MS) is commonly diagnosed in women of childbearing age. Having a greater understanding of the effects of pregnancy on the course of MS will lead to improved family-planning counselling for women. We found well-established evidence for a protective effect of pregnancy on relapse occurrence in historical cohorts. More recent studies suggest that the protective effect of pregnancy against relapse may be lost in those women with more active disease treated with high efficacy therapies. Furthermore, a strong body of evidence suggests that gravidity after diagnosis of MS does not lead to worse long-term outcomes. More contentious however, is whether pregnancy can delay a first episode of demyelination or a confirmed diagnosis of MS. This review provides a detailed analysis of the literature relating to the clinical effects of pregnancy on MS outcomes across a woman's reproductive lifespan.

Ondansetron 8 mg and 4 mg with normal saline against post-operative headache and nausea/vomiting after spinal anesthesia: a randomized double-blind trial

The study aims to evaluate the efficacy of ondansetron in preventing post-spinal headache, considering the high prevalence of the headache in pregnant women and the common use of the adjuvants for prophylaxis against post-operative nausea and vomiting (PONV). This double-blind clinical trial included the 195 patients who were referred to Taleghani Hospital (in Arak, Iran) for cesarean section (C/S) under spinal anesthesia, and then the subjects were assigned to three equally sized groups using block randomization. Participants in the first, second, and control groups received 8 mg, 4 mg of ondansetron, and normal saline, respectively, 5 minutes before surgery. A final volume of 5 cc was prepared by adding normal saline. Participants were examined for headache one week after surgery, and then data analysis was performed using SPSS 20. The incidence of post-spinal headache was significantly higher in the placebo group than in the ondansetron 8-mg and 4-mg groups at 24 hours after surgery (P < 0.010). But, no significant difference was observed between two ondansetron groups (P ≤ 0.05). The overall incidence of the headache was generally lower in ondansetron 8-mg (26.66% vs. 33.68.05%) and 31.66% in ondansetron 4-mg (P < 0.001). Moreover, the PONV incidence was significantly higher in the placebo group than in the other two groups at 24 hours (P < 0.001). The hemodynamic variables were same in three groups. The ondansetron 8-mg dose can be effective to prevent headache after spinal anesthesia for C/S. Moreover, the ondansetron 8-mg and ondansetron 4-mg have same effect in control of PONV after spinal anesthesia for C/S.

Uncovering the link between reproductive factors and multiple sclerosis: A case-control study on Iranian females

BACKGROUND

Increase of MS prevalence in females compared to males, especially in reproductive age, highlights the important role of reproductive factors in MS pathology.

OBJECTIVES

We examined the association between females' reproductive age-related factors and MS risk.

METHODS

A case-control study including 399 cases and 541 controls was carried out. The adjusted associations between MS risk and reproductive variables including age at menarche, oral contraceptive pills (OCPs) use history, OCP usage duration and age at first use, history of assisted reproductive technologies (ARTs) use, parity history, age at first childbirth and the number of parities, abortion and exclusive breast feeding > 2 months were assessed.

RESULTS

We found protective relationships between MS and older age at menarche (OR = 0.90 {95% CI = 0.82-0.98}), ART use history (OR = 0.45 {95% CI = 0.21-0.99}), older maternal age at first childbirth (OR = 0.94{95% CI = 0.89 - 0.99}) and higher number of parities(OR = 0.61 {95% CI = 0.49 - 0.75), whereas using OCPs was associated with higher risk of developing MS (OR = 1.80 {95% CI = 1.35-2.41}).

CONCLUSIONS

Links were noted between a number of reproductive factors and risk of MS.