Endometriosis as a comorbidity - what do we actually know?

Kiristar

Senior Member (Voting Rights)
Having just been diagnosed with severe deep infiltrating endo for the second time, I wanted to know what science tells us about the overlap between the two conditions?

Both seem to have an immune defect as a mediator?

Nb. I'm severe and too unwell to actually read papers myself at the moment
 
Having just been diagnosed with severe deep infiltrating endo for the second time, I wanted to know what science tells us about the overlap between the two conditions?

Both seem to have an immune defect as a mediator?

Nb. I'm severe and too unwell to actually read papers myself at the moment
I can't answer the question but I just wanted to post that I'm another ME/CFS patient who has also had endometriosis, confirmed by surgery.

For me, surgical removal (excision, not laser ablation) of the endometriosis stopped almost all of my pain. But I have read that surgery does not help some folks.

Another issue is whether your health insurance will cover surgery. Sometimes insurance will only pay a small amount even if the surgery that's needed to remove all the lesions is several hours long.
 
I appreciate you can't read the papers, but I'll post links that others following the thread may be interested in.

We have threads for —

Identification and Validation of Novel Combinatorial Genetic Risk Factors for Endometriosis across Multiple UK and US Patient Cohorts (2025)

Evaluation of Long-COVID Syndrome in a Cohort of Patients with Endometriosis or Adenomyosis (2025)

This is a review article from April —

Twenty-five years of research in endometriosis (2025)

And these are papers that might suggest overlapping mechanisms, from the last 2-3 months (I haven't had a chance to read any of these, but nearly all are open access) —

Integrative Single-Cell Analysis Reveals Iron Overload-Induced Senescence and Metabolic Reprogramming in Ovarian Endometriosis-Associated Infertility (2025)

Emerging Mechanisms of NK Cell Dysfunction in Endometriosis: The Role of Autophagy, Metabolism, Cytokines, Exosomes, and Trogocytosis (2025)

The Gut–Endometriosis Axis: Genetic Mechanisms and Public Health Implications (2025)

Leptin receptor polymorphism increases the risk of painful symptoms in Brazilian women with endometriosis (2025)

Beyond pelvic pathology: retinal microvascular rarefaction as a systemic marker in endometriosis (2025)

CCN5 negatively regulates TGF-β-induced endometriosis associated fibrosis through Wnt/β-catenin signaling via Smad3-dependent mechanism (2025)

Complement and coagulation cascade cross-talk in endometriosis and the potential of Janus Kinase inhibitors—a network meta-analysis (2025)
 
Having just been diagnosed with severe deep infiltrating endo for the second time, I wanted to know what science tells us about the overlap between the two conditions?

I think science says there is no overlap in terms of how they are defined. There will be some overlap of symptoms but that is true of all sorts of things. I do not know of any data on them occurring together more often than by chance.

I am not sure what 'comorbidity' is intended to imply. If it is just some other illness someone has, like diabetes, then there will be cases by chance. There tends to be an implication that a comorbidity is something seen more often than by chance and for most of the things suggested for ME/CFS the evidence looks unconvincing.

I am not sure that ME/CFS has anything to do with immune defects (the old idea of being an immunodeficiency was never based on good evidence). ME/CFS may well involve immune events at least in getting started. I am not aware of any evidence for immune events being important in endometriosis. There may be theories out there but I cannot immediately see how it would fit.

So my impression at present is that they probably have nothing to do with each other.

From a genetic point of view it would be interesting if they share genetic risk factors. (We know that having two X chromosomes rather than XY is a risk factor for both.)
 
Thank you @SNT Gatchaman
I recall the NK cell problem as a newly emerging theory last time round, so will try to catch up if I feel better.

I know at first glance they seem different but both share fatigue as a symptom and I can't help but see parallels in the immune system failing to clear viruses in ME/CFS (I know this is just one of many theories) and the immune system failing to clear endometrial cells in the wrong place in endometriosis. As a layperson that feels like more than a coincidence and is what prompted my question.

I appreciate the shared skew towards women probably is not significant
 
The trouble with conditions like endometriosis is that they're really common. Something like one in 10 women are thought to get it, so you'd need a very large study to work out whether occurrence is the same, more common or less common in people with ME/CFS.

Also, some of the older ones won't have been diagnosed. GPs didn't used to have any interest in it, and I suspect many didn't really believe in it. After decades of struggle and medical appointments, mine was 'diagnosed' during a colonoscopy years after menopause (a lot of adhesions and scarring, apparently).
 
The trouble with conditions like endometriosis is that they're really common. Something like one in 10 women are thought to get it, so you'd need a very large study to work out whether occurrence is the same, more common or less common in people with ME/CFS.

Also, some of the older ones won't have been diagnosed. GPs didn't used to have any interest in it, and I suspect many didn't really believe in it. After decades of struggle and medical appointments, mine was 'diagnosed' during a colonoscopy years after menopause (a lot of adhesions and scarring, apparently).
I wonder if you could perhaps take the much less common, deep infiltrating severe form of it to counter that . Plus we have biobanks now with large data pools.

I so empathise with the delayed diagnosis. I had it from menarche so it took 30 years to get mine first diagnosed, and that was by a lucky coincidence that my GP had a relative in a specialist Endometriosis unit so was particularly aware. Awareness seems to have mushroomed over the last ten years in the UK.
 
I know at first glance they seem different but both share fatigue as a symptom and I can't help but see parallels in the immune system failing to clear viruses in ME/CFS (I know this is just one of many theories) and the immune system failing to clear endometrial cells in the wrong place in endometriosis. As a layperson that feels like more than a coincidence and is what prompted my question.

But why should this be more than coincidence?
Pretty much any illness with unpleasnat symptoms will lead to fatigue. I don't know of any evidence for endometriosis causing fatigue other than through pain etc. Since nobody seems to understand endometriosis presumably nobody has any scientific evidence for such a mechanism.

As far as I can see interest in NK cells in ME/CFS has pretty much fizzled out, presumably because the people who originally suggersted it found they could not repeat and extend the findings. My impression is that the story arose forty years ago when someone suggested ME/CFS might be like AIDS, which it isn't. The situation for endometriosis looks similar to the extent that the review from some chaps in Iran basically says that someone though they found something wrong with NK cells 30 years ago but nothing has become any clearer since.

NK cell assays are very hard to get reliable, and almost impossible to interpret unless you have a major genetic defect. People look at them in mystery illnesses and report things because it is so easy to get strange results I suspect.

I don't think we have good evidence of people with ME/CFS failing to clear viruses. Although NK cells get rid of unwanted self cells in some circumstances I doubt there is any good reason to think that endometriosis is due to lack of NK cells. I may be wrong but as far as I know people with documented NK deficiencies have neither ME/CFS nor endometriosis more than others.

If you look for similar speculative theories in the scientific literature you will find similar theories for just about anything, so I don't think this is even coincidence - more just the usual sea of useless data being churned out in reviews by people who don't actually know much about the science.
 
I am not sure if it means anything, but I have biopsy-confirmed endometriosis, and I have really severe early-cycle fatigue that is not just caused by pain. It occurs even when my pain is well controlled. It is the closest thing I’ve ever felt to ME fatigue and is quite different from regular healthy-person fatigue. I had it years before I ever had ME.

I’m curious if anyone else with endo thinks the fatigue is similar to ME?

I have heard many times that endo is more common in ME patients, but I have doubts about how reliable that info is. It would be nice to know for sure. Endo often goes undiagnosed, so I could see the supposedly elevated rate in ME being caused by ME patients being less trusting of their doctors and figuring out what they have rather than the rate actually being higher.
 
I am not sure if it means anything, but I have biopsy-confirmed endometriosis, and I have really severe early-cycle fatigue that is not just caused by pain. It occurs even when my pain is well controlled. It is the closest thing I’ve ever felt to ME fatigue and is quite different from regular healthy-person fatigue. I had it years before I ever had ME.

I’m curious if anyone else with endo thinks the fatigue is similar to ME?

I have heard many times that endo is more common in ME patients, but I have doubts about how reliable that info is. It would be nice to know for sure. Endo often goes undiagnosed, so I could see the supposedly elevated rate in ME being caused by ME patients being less trusting of their doctors and figuring out what they have rather than the rate actually being higher.
My Endo fatigue occurs a day or two before my menstruation.

I'd say it's comparable to a normal pem in severity ie it puts me in bed, grey with a hot water bottle and I can't do anything, but it feels different (like my blood has drained out of me) and symptoms differ. It is straight fatigue without the symptom exacerbation element.
 
My endometriosis symptoms went away completely when I recovered from ME. So I do believe they are connected. My reactive hypoglycemia also stopped when I started to feel better and there is research showing that endometriosis patients have reactive hypoglycemia due to increased insulin sensitivity.
 
Back
Top Bottom