Whenever new clinical trials are carried out, as a rule of thumb, researchers always first recruit young, healthy men because they are the least likely to be vulnerable to side effects. Women are not usually targeted as participants in early-stage clinical trials due to the unknown adverse effects on fertility and pregnancy.
In fact, in terms of drug development, fertile women have always been given special care because any side effects that compromise their fertility and ability to carry a normal pregnancy to term can have long-term and potentially litigious consequences.
The biological reaction of a drug can differ drastically between biological males and females. A group of Spanish researchers set out to conduct a literature review of the impact of menopause on multiple sclerosis and published their findings in the Multiple Sclerosis Journal. It is their study we will examine in this article.
Multiple Sclerosis in Women
Multiple sclerosis is a neurodegenerative disorder of the central nervous system that can cause long-term disability. Although the exact mechanisms of action of the disease are unknown, it is at least clear that the immune system is heavily involved.
In recent years, the number of female patients with multiple sclerosis has increased. Currently, the female-to-male ratio stands at 3:1. Women with multiple sclerosis tend to have an earlier age of onset, more frequent relapses, and quicker disease progression.
Read more about multiple sclerosis etiology
What could possibly account for the disparity in etiology between men and women? The authors of the study offer a possible explanation: “Fluctuation of sex hormone levels during the different physiological stages of women’s reproductive life (menarche, puberty, pregnancy, puerperium, and menopause) seems to influence both the risk and the prognosis of disease.”
Research suggests that periods of high levels of estrogen are considered protective, causing a dampening of the inflammatory response. If we look at the 5 stages of a woman’s reproductive life – menarche, puberty, pregnancy, puerperium, and menopause – we know the least about the effects of menopause, the final stage of a woman’s reproductive life, on the risk and prognosis of multiple sclerosis.
A number of physiological changes take place in menopause that might plausibly affect the disease progression of multiple sclerosis. During menopause, women experience the loss of ovarian estrogen. Since estrogen has been linked in previous studies to brain health, the loss of ovarian estrogen can lead to a decrease in brain repair, which would then accelerate neurodegeneration and thus quicken the disease progression of multiple sclerosis.
Read more about multiple sclerosis prognosis
Given the global aging trends, with senior citizens likely to make up a higher percentage of the population than in other periods of history, it is incredibly important that we invest in elderly care research now. We need to redirect our resources to strengthen our grasp of elderly care or risk calamity on our healthcare systems in the future.
The Menopause and MS Study
The Spanish researchers shared this concern and thus conducted a literature study on the effects of menopause on multiple sclerosis. The researchers wanted to focus on 3 specific areas to learn how menopause affects multiple sclerosis:
- The effects of menopause on the disease progression of multiple sclerosis.
- The effects of multiple sclerosis and disease-modifying drugs (DMDs) on menopause.
- The effects of hormonal replacement therapy (HRT) on menopausal women with multiple sclerosis.
The researchers investigated 68 articles based on online searches that included the terms “multiple sclerosis” and “menopause.” After conducting a thorough literature review, the researchers reported their findings, which will be presented according to the order in which they answer the questions above:
- Menopause was found to aggravate multiple sclerosis symptoms, but only transitorily. Researchers found 2 studies that identified an inflection point on the Expanded Disease Disability Scale (EDSS), suggesting that menopause is an independent risk factor for disability progression. However, it should be noted that another study looking at full EDSS trajectories from the premenopausal stage to postmenopause failed to identify an inflection point on the EDSS.
- Multiple sclerosis and DMDs did not seem to affect the age of menopausal onset.
- Researchers observed a low prevalence of HRT use among participants, but the results showed that HRT improved the quality of life of users and was not harmful to women with multiple sclerosis. However, there were insufficient data to postulate the full effects of HRT on multiple sclerosis.
Elderly Care: No Longer Marginalized
A major disadvantage when conducting hormonal studies is the possible interference of other hormones that are not the main focus of the study. The authors of the study wrote, “To date, it is not possible to draw definite conclusions regarding whether menopause is an independent risk factor for disability accumulation secondary to hormonal factors or whether the effect is due to aging itself” and therefore suggested that “properly designed, longitudinal and prospective studies are mandatory.”
Indeed, as elderly medicine comes more and more into the spotlight, a greater understanding of elderly diseases (especially as they relate to menopause) and a greater grasp on how to treat them can end up saving healthcare costs in the long run and make healthcare access more equitable for all.
Midaglia L, Otero S, Baró F, Montalban X, Tintoré M. Menopause and multiple sclerosis: influence on prognosis and role of disease-modifying drugs and hormonal replacement therapy. Mult Scler. Published online August 28, 2020. doi:10.1177/1352458520952022
Ladeira F, Salavisa M, Caetano A, Barbosa R, Sá F, Correia AS. The influence of menopause in multiple sclerosis course: a longitudinal cohort study. Eur Neurol. 2018;80(3-4):223-227. doi:10.1159/000496374