Approximately 40% of the people affected by Parkinson’s are female. This number can vary across regions, but women still make up a large portion of the affected community.
That said, there is unfortunately very little research investigating women’s issues in Parkinson’s.
There are now efforts to correct this situation, however, and this change is being brought about by members of the affected community.
In today’s post, we will discuss some of what is known about how Parkinson’s affects women differently.
Why is today – the 8th March – called International women’s day? (backdated due to @#%$£&* technical issues!).
I don’t actually know. Perhaps because it’s politically correct that everyone should get their own day/month now?
The United Nations began celebrating International Women’s Day on the 8th March in 1975. But observation of the day date back to the early years of that century, and although the suffrage movement was occurring at the same time, International women’s day was very much a socialist idea.
And this shows itself in the timeline of events. For example, International Women’s Day was first observed on the 19th March, 1911 in Germany thanks to socialist activists like Luise Zietz, Käte Duncker and Clara Zetkin. But it wasn’t until 1918 that women were actually given the right to vote.
And remarkably, it was not until 1977 that the United Nations General Assembly invited its member states to proclaim the 8th March as the “UN Day for women’s rights and world peace”.
Interesting. But what does this have to do with Parkinson’s?
There is an imbalance in the amount of research being conducted on women in Parkinson’s.
In particular, there is a poverty of information regarding aspects of daily life for women living with Parkinson’s, especially those with young onset Parkinson’s.
What do you mean?
If you go to the medical research search engine Pubmed, and type in Parkinson’s and menopause, there are only 107 publications (dating back to 1971, 41 of them since 2010). To put that in context, there are over 105,000 research reports on Parkinson’s on the pubmed database. And most of them are not about menopause research, they simply mention the word menopause in their text. Similarly there are only 25 reports on parkinson’s and menstruation (and only 6 of them have been conducted since 2000!?!?).
Searching for male associated key words such as parkinson’s and prostate yeilds 177 publications (104 of which have been published since 2010 only).
And searching for Parkinson’s and male results in 43,000 reports, but searching for Parkinson’s and female only gives 36,000 reports.
So why the disparity?
That’s a great question. One has to pause and scratch one’s head.
What are the differences between men and women with regards to Parkinson’s?
That’s another great question. Let’s have a look.
Firstly, there is a higher frequency of Parkinson’s in men than women, but not by much.
There have been numerous publications highlighting this higher rate of Parkinson’s in males. For example, this large study:
Title: The Incidence of Parkinson’s Disease: A Systematic Review and Meta-Analysis
Authors: Hirsch L, Jette N, Frolkis A, Steeves T, Pringsheim T.
Journal: Neuroepidemiology. 2016;46(4):292-300.
PMID: 27105081 (This report is OPEN ACCESS if you would like to read it)
In this study, the researchers conducted a meta-analysis (that is an analysis of a combination of results from different studyies) from 27 international studies assessing the incidence of Parkinson’s. The analysis found that the overall incidence of Parkinson’s in females who were 40 years and older was 37.55 per 100,000 person-years.
What does that even mean?
Epidemiology is a curious world. They divide the incidence of a condition into two areas: Proportion and rate.
Incidence proportion is the percentage of new cases of a condition within a specified time period (eg. if a population initially contains 1,000 non-diseased persons and 28 develop a condition over two years of observation, the incidence proportion is 2.8% per two years).
This can be a messy number, however, when you are looking at different datasets, and so most researchers use incidence rate.
Incidence rate is the number of new cases per population at risk in a given time period. So in the example above, the incidence rate is actually 14 cases per 1000 person-years, because the incidence proportion (28 per 1,000) is divided by the number of years (two). This number allows for comparative analysis across datasets with different time frames.
Clear as mud?
The researchers found that the overall incidence of Parkinson’s in males over 40 years of age was 61.2 per 100,000 person-years (compared to the female 37.55 per 100,000 person-years).
In females, the researchers found that the incidence rates of Parkinson’s increased steadily over time (from 3.26 per 100,000 person-years at age 40-49 to 103.48 at age 80+). The rates peaked between the ages 70 and 79 in a majority of studies analysed, which demonstrated one curious difference to males – the incidence in males continued to rise after the age 80 according to approximately half the number of studies.
And this pattern of females having a reduced rate of Parkinson’s compared to men is a common trend around the world, except for one country: Japan.
Japan is the only country in the world where females have a higher incidence of Parkinson’s disease than men (and we have no idea why – Click here to read more on this).
Curiously, the incidence of Parkinson’s in people diagnosed under the age of 40 also has a difference according to sex – males again have a higher incidence (59% males vs 41% females – Click here to read more about this). This is particular strange given that there is a stronger genetic component to young onset Parkinson’s, which one would assume would affect the sexes equally.
Thus, there may be something about being female that reduces one’s risk of developing Parkinson’s.
Probably worth investigating…
Interesting. What else do we know about women and Parkinson’s?
Recently there was an interesting analysis of clinical data associated with the features of Parkinson’s:
Title: Sex differences in LRRK2 G2019S and idiopathic Parkinson’s Disease
Authors: San Luciano M, Wang C, Ortega RA, Giladi N, Marder K, Bressman S, Saunders-Pullman R; Michael J Fox Foundation LRRK2 Consortium.
Journal: Ann Clin Transl Neurol. 2017 Oct 19;4(11):801-810.
PMID: 29159192 (This report is OPEN ACCESS if you would like to read it)
In this study, which involved the Michael J Fox Foundation LRRK2 Consortium, the researchers collected clinical data from 530 people with LRRK2-associated Parkinson’s (Click here to read more about LRRK2-associated Parkinson’s) and 759 people with idiopathic Parkinson’s (with no Parkinson’s associated genetic risk factors).
When the investigators compared the genders, in the idiopathic Parkinson’s group, they found that males had worse scores on activities of daily living, but lower complications of therapy (UPDRS-IV). They also found that women had higher olfaction scores and were able to thermoregulate their bodies. In addition, women were more likely to have reported a family history of Parkinson’s.
By comparison, in the LRRK2-associated Parkinson’s group, the investigators found no male predominance among individuals carrying the G2019S genetic variation (and this is in agreement with previously published results – click here and here to read more about that). Women with LRRK2-associated Parkinson’s generally had worse motor complications (as determined by UPDRS-IV), but better olfaction than men.
When the researchers compared clinical results between individuals with and without LRRK2 genetic risk factors, men with LRRK2-associated Parkinson’s demonstrated lower motor and higher cognitive scores than men with idiopathic Parkinson’s, and women with LRRK2-associated Parkinson’s had worse motor complications (as determined by UPDRS-IV) and higher rates of dyskinesia compared to women with idiopathic Parkinson’s. Curiously, regardless of gender individuals with LRRK2-associated Parkinson’s had better olfaction than their idiopathic Parkinson’s counterparts.
Interesting. But what about more women-related matters, like the menstrual cycle? What effect does Parkinson’s have on this?
Given that Parkinson’s is generally a late-onset condition (post-menopause), there is very little research on the topic of menstruation and how it can affect women with Parkinson’s.
In 2002, this report was published and it provides a lot of useful data:
Title: Coping with menstruation: understanding the needs of women with Parkinson’s disease.
Authors: Tolson D, Fleming V, Schartau E.
Journal: J Adv Nurs. 2002 Dec;40(5):513-21.
In this study, the researchers recruited 18 women who had been diagnosed with young onset Parkinson’s. The majority of the women in the study were diagnosed with Parkinson’s around the age of 39 years (the youngest age of diagnosis was 18). Most of them had lived with early signs/symptoms of the condition for some years prior to their diagnosis. The average age of the participants ranged from 34 to 56 years, with an average age 47 years.
Two of the women had had hysterectomies, and the remaining 17 had naturally occurring cycles. Three of the 18 women reported that there had been no change in their periods following the onset of PD, while the remaing 15 women all reported a worsening of their period-associated issues (pain and fatigue in particular).
Most of the women suggested that their Parkinson’s symptoms were often more exaggerated during their period. In addition, the effectiveness of their PD medication was reduced and their ‘OFF times’ increased (OFF time being periods of limited movement).
The study also provided advice for clinicians and attending nurses, suggesting that women who experience an increase in the volume of blood lost during their periods should be monitored for signs of anaemia, and also given advice on the management of diet and fatigue.
The following poem was included in that study:
I am writing this poem to you today,
Because I’d like to help in any way.
I have Parkinson’s, don’t know the cause.
But sure doesn’t like my menopause.
Most of the time I manage very well,
Considering I’ve had it for a seven year spell.
Then the time of the month comes along again,
I’ve finished my period, but the feelings remain.
Sometimes I’m slow and need a push,
My tablets don’t work, and I’m rather flushed.
I can’t turn over in bed at night,
But I never lose my appetite.
I’m giving HRT a go to see,
If my hormones will settle down in me.
I’d be pleased to help in any way,
To meet with others who feel this way.
I’ll battle on, fight Parky everyday.
God give me strength till cure comes our way.
What about pregnancy?
Much of the data that has been generated on this topic has been anecdotal, simply because the combination of Parkinson’s and pregnancy is very rare. Having said that, it is still very useful to have information available for individuals who find themselves in this particular situation.
There was recently a very useful review on this topic:
Title: Parkinson’s disease and pregnancy: An updated review.
Authors: Seier M, Hiller A.
Journal: Parkinsonism Relat Disord. 2017 Jul;40:11-17.
The researchers conducted a literature search and compiled all of the available case studies of pregancies involving individuals with Parkinson’s and the use of Parkinson’s medications. They found that there were no issues reported with regards to fertility, conception or the birthing process for women with idiopathic Parkinson’s.
EDITOR’S NOTE: There has even been a successful twin pregnancy in an individual with PARKIN-associated autosomal recessive juvenile parkinsonism (Click here to read more about this).
The investigators reported “No major bleeding issues or delivery complications were mentioned in the cases reviewed other than one case of placental abruption at 32 weeks in a 34-year-old woman. The baby was delivered safely by cesarean-section and both mother and child recovered well” (Source).
The researchers found that Levodopa has been used in 114 documented pregnancies. Only 47 of those pregancies actually involved individuals with Parkinson’s and one of those PD-associated preganacy actually involved intestinal infusion of levodopa (Click here to read more about that). The data from these pregancies indicate that levodopa use during pregnany was not associated with an increased rate of spontaneous abortion or other birth complications.
What about breast feeding?
There is very limited data on the degree to which Parkinson’s medications are present into breastmilk and the effect that these medications may have on an infant. Thus, it is typically not advised that one should breastfeed while taking any anti-Parkinsonian medications.
If you are currently taking Parkinson’s medication and you plan to breast-feed, please seek advice from your doctor, obstetrician or Parkinson’s nurse.
Where else can I learn more about women with Parkinson’s?
As I come across more research I’ll post it here, but please note the Spotlight YOPD website has information about women’s issues in Parkinson’s (Click here to read that page).
The European Parkinson’s Disease Association (EPDA) also has a very good webpage for women with Parkinson’s (Click here to read more about that).
In addition, there just happens to be a conference coming up very shortly – which you can attend in person or watch online – which is dedicated to women with Parkinson’s.
The Parkinson’s Eve conference will be held on the 10th April (the day before World Parkinson’s day) from 09:30 – 17:00 at the Mercure Leicester – The Grand Hotel, Granby St, Leicester (LE1 6ES) UK.
Critically, this is a conference for women with Parkinson’s organised by women with Parkinson’s. But it is not just for women – anyone can attend/watch (male or female). And it is a satellite conference for the larger InsightintoPD conference which will be taking place on the 11th April.
Do you like the play on words with the Parkinson’s Eve conference name?
So what does it all mean?
While there is a great deal of research currently focused on trying to understand the biology of Parkinson’s and finding curative therapies, there is also a need to investigate different aspect of the condition that affect quality of daily life in the community. And these different aspects of the condition can differ between the genders and the various age brackets affected.
Although females makes up about 40% of the affected community, there is limited research on some aspects of life that are important to and affect women. In writing this post, I was rather disturbed by how little data there is on some of these topics, and it left me wondering where women with specific questions can actually turn to to get answers. If there is little or no data, what is the advice provided based on?
One potential solution to this problem – in this age of social media and interconnectedness – is for surveys to be generated and conducted online by the community itself. An alternative approach is for patient-organised conferences like Parkinson’s Eve to tackle some of these topics. I also think that there is a very real opportunity for several researchers to make a name/career for themselves by conducting some research into some of these niche areas.
The output of these efforts would certainly be greatly appreciated by women with Parkinson’s who are seeking answers to questions which are not readily available at present.
The adolescent years were a confused and baffling epoch for yours truly. I had very little luck with the ladies, and in a state of frustration and dispair I sought my grandfather’s advice (I think I was 12 when this happened).
ME: Grandpa, can you explain women to me?
GRANDPA: (With a gentle smile) There’s only three things you need to know. Three rules if you like. Number 1: Be prepared to wait, because she’s worth waiting for. Number 2: Never keep a lady waiting, because you are not worth waiting for. And number 3: Always put the toilet seat down. Always.
Sage advice now as I look back.
It only left me further confused and baffled at the time, but with subsequent experience I have come to see the wisdom in it all.
I miss my Grandpa.
EDITOR’S NOTE: The author of this blog has no association with the organisers of the Parkinson’s Eve or Insight into Parkinson’s conferences. He was invited to be a speaker at the Parkinson’s Eve conference, but due to conflicting events during Parkinson’s Awareness week was not able to attend. That said, the information provided here has not be requested by the organisers of the conference, nor is the author receiving any form of compensation for mentioning it. It is simply being shared because the author thought the event was a novel and brilliant idea that readers may be interested in.
The information provided by the SoPD website is for information and educational purposes only. Under no circumstances should it ever be considered medical or actionable advice. It is provided by research scientists, not medical practitioners. Any actions taken – based on what has been read on the website – are the sole responsibility of the reader. Any actions being contemplated by readers should firstly be discussed with a qualified healthcare professional who is aware of your medical history. While some of the information discussed in this post may cause concern, please speak with your medical physician before attempting any change in an existing treatment regime.
The banner for today’s post was sourced from Christie’s
7 thoughts on “The Eve of Parkinson’s”
Understanding sex differences in PD could lead a better understanding of the disease process and possibly even improved treatment and prevention strategies for both sexes.
The authors of one study on pregnancy in women with PD stated that estriol – the predominant form of estrogen in pregnancy – may be to blame for worsening of symptoms.* That’s something women with PD who want to try hormone replacement therapy may want to discuss with their doctors. Many practitioners these days encourage use of estriol instead of estradiol since it is viewed as a being ‘weaker’ and ‘safer’.
*can’t find the reference for the original study, but it seems to be alluded to here:
I wonder about the role of equol; equol can blunt the effects of both DHT and estradiol. S-equol is a metabolite of daidzein, and is produced in the guts of people who consume soy and have the right gut flora. Foods that promote the ‘right flora’ are maltose (a sugar found in sweet potatoes) and seaweed; Japan has a high proportion of equol-producers. S-equol is also used as a supplement in Japan for control of menopause symptoms. Racemic equol is sold as a supplement for prostate health. OTOH racemic equol is interesting in it has been found to upregulate production of nerve growth factor [PMID 28587197] and equol is supposed to reduce neuroinflammation [PMID 28264445]. So maybe equol is protective, but not as protective as estradiol? IDK – throws up hands.
Another possibility is it might have something to do with natto/spermidine consumption.
Forgot to mention – progesterone is an NLRP3 inhibitor [PMID: 28830026] (in mice).
Thanks for the really interesting comment. The Japanese situation is very curious – I explored it in a very early SoPD post (https://scienceofparkinsons.com/2015/11/28/the-difference-between-men-and-women/), but have never really found a satisfactory answer.
I too couldn’t find the Estriol reference either, but I did find a report suggesting that Estriol (of all the sex hormones) significantly exert anti-aggregation and fibril-destabilizing effects on alpha-synuclein aggregates ( https://www.ncbi.nlm.nih.gov/pubmed/19289119 ).
Progesterone is interesting too, particularly from the standpoint of prodromal PD ( https://www.ncbi.nlm.nih.gov/pubmed/28192111 ) and like wise the 5α-reductase inhibitor Dutasteride ( https://www.ncbi.nlm.nih.gov/pubmed/26006269 ; https://www.ncbi.nlm.nih.gov/pubmed/28982631 ), which inhibits the transformation of progesterone to its metabolites.
Lots of interesting avenues to explore. The main issue with the sex hormone research is that all of it seems to point towards the need for very early treatment, delayed treatment appears to have no effect. All of it also appears to be of an anti-inflammatory nature.
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If I ever find that article on pregnancy in PD that implicates estriol, I will post the reference. It is really bugging me since I’m sure I read it on PMC. My computer died a few weeks ago and I lost all my FireFox bookmarks and I felt like I had lost half my brain. I was never happy with just using bookmarks, so I finally set up a Zotero account. It has become the beginnings of my (much needed) brain externalization project. The account is publicly accessible, but one needs a Zotero account to access it.
Thanks for summarizing the knowledge available on this important topic. And for making it accessible to the educated lay person.
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It seems unscientific to make use of the term “sex” when “gender” would seem to be more precise.
FB PD groups now contain a majority of women. Are women more inclined to join FB? Sorry you’ve moved on from your Cambridge e-mail.
I was taught as a bio major back in the late 80’s that ‘sex’ was the preferred term for scientific writing on biological sex differences.