The characteristics of Parkinson's disease in women differ from those in men, as they are less susceptible to it, and there is a link between their infection and factors extending from the age of menopause to the number of pregnancies, according to a recently published French study.

In a statement to Agence France-Presse, epidemiologist Marianne Canonico, who directed a study on the risk factors that make women vulnerable to Parkinson's disease, said, "Studies on this disease in women are few because it is more common among men."

So there is certainly an effect of the gender of people, whether in terms of the prevalence of this disease, which gradually affects the ability to move, which is the second neurodegenerative disease after Alzheimer's, or in terms of its symptoms and manifestations.

A 2019 abstract published in the journal Parkinson's Disease noted that "the risk of developing Parkinson's disease is twice as high in men, but the death rate is higher in women as the disease progresses faster in them."

In addition, "the symptoms (...) differ between men and women," according to the study's authors.

Falls are recorded more frequently in women, while men tend to salivate more than women excessively, and become unable to walk due to the loss of the ability to move the legs.

There is still a lot of ignorance about the reasons for these differences, and researchers are still in the stage of identifying the risk factors that affect women specifically.

It is this topic that is addressed by the study conducted by Marianne Canonico of the French National Institute of Health and Medical Research, and published in the leading journal "Brain" in the field of neuroscience.

The study represents an important advance, given that it was conducted on the largest scale to date in terms of the number of people included, as well as the period it covers.

The study is based on data collected over the last 30 years on nearly 100,000 French women.

And different diseases appeared over time, which allowed the researchers to compare infection with other factors.

Protective hormones

The study concluded that Parkinson's disease affects more women who have stopped menstruating for unnatural reasons, especially before the age of 45 years, and who have given birth to more than one child.

The risk is also greater for women whose periods appear earlier or later than the average age of 12-13 years.

However, these conclusions do not cause women who belong to one or more of these categories to panic, as the risks are slightly higher but are unlikely to change the situation at the individual level.

Kanoniko explained that these factors "do not make the risk four or five times higher, it is not the same as the effect of tobacco on lung cancer!".

And she considered that the importance of this study rather lies in the fact that it allows "to understand the mechanisms that may contribute to Parkinson's disease in women."

The study partly meets one of the most prominent hypotheses that are put forward to explain the lower incidence of infections in women compared to men, according to which estrogen - the main female hormone - plays a protective role against this disease.

Early menopause

This would explain, for example, that early menopause increases risk.

In fact, estrogen production stops earlier than average in women who menopause prematurely.

In contrast, when puberty is later than average, estrogen production begins later.

But the hypothesis does not fully coincide with the results of the study.

Why is this disease more common in women who become pregnant more than once, even though estrogen levels rise in women during pregnancy?

In this sense, the debate remains largely open, but this study allows future research to be better directed, in the hope of developing effective treatments for Parkinson's disease one day.

The epidemiologist at the French National Institute of Health and Medical Research stressed the need for further studies, and said, "If estrogen really has a role, we can work, for example, on a more accurate study of its effect on brain mechanisms that play a role in Parkinson's disease."