We've discussed CRP on a number of threads. There are some hints of mildly raised CRP in ME/CFS and some suggestion that levels may track with fluctuations of illness severity. But, there are a lot of confounding factors. I'm going to link some of the papers and discussions here. When completing the poll try to choose a range that reflects most of your CRP levels, rather than your highest ever level. If there is an odd one that you know was related to a specific infection unrelated to ME/CFS, ignore it.
CRP measurement First some background on the measurement from some of the discussions. Levels are often reported in mg/L. Sometimes levels are reported in mg/dL - to convert to mg/L, multiply by 10. HS-CRP is high sensitivity CRP, obtained by a test that can accurately identify low levels. I think the reported levels are comparable with the standard CRP test, although there may be some differences in normal level ranges resulting from different tests. Pearson et al notes that 95% of the population has a CRP less than 10mg/L: Pearson et al also notes that small differences in low levels of CRP have been found to be predictive of heart disease. Jonathan Edwards has commented here on CRP levels based on his experience as a rheumatologist:
What does CRP do? CRP is found in blood plasma and produced by the liver, is often said to be a marker of inflammation. It activates the complement system. Wikipedia says But, as with most things, it is more complicated than that, for example:
What do studies in ME/CFS and related diseases tell us? Association between C-reactive protein and chronic fatigue syndrome: a meta-analysis, 2017, Wang et al This review found 7 studies. Selection criteria of participants looks to be loose, which is a problem. (4+4=7 is due to the Sulheim study having two case groups) Woolie had this to say: So, a small increase over healthy controls. But questions about how many people in the studies actually had ME/CFS. Also differences in BMI may account for the different mean CRPs, and there is the possible problem of the healthy controls being 'too healthy' as in not being representative of the range of CRP levels in normal people.
That's me done for the moment, but hopefully I or other people can have a look at the other evidence we have on CRP levels in ME/CFS and related diseases. I think the conclusion I came to for the 2017 review may apply to a number of the studies.
I've only been able to find 3 results, one was high (23) but that was during an acute infection. The other two were reported as <1 and 1mg/L respectively, so nothing very spectacular to see (I ticked <1)
I've always been puzzled by the difference between CRP and CRP-HS. In the CRP link it says : In the CRP-HS link it says : As far as I can tell (and I realise I could well be wrong), CRP gives an indication of how much inflammation a person has from multiple different possible sources e.g. infection or arthritis, and CRP-hs gives an indication of how high a risk a person has of cardiovascular disease. In both cases the same thing is being measured, but the CRP-hs test is just more accurate. So, I don't understand how measuring it more accurately can change what it indicates?
The Beentjes study looked at BMI (reported in the second draft I think) and there was not much difference. But I think we may also have to consider activity levels. The difference in CRP in ME/CFS looks to be very tiny. Quite a lot of plasma proteins shift with recumbency (albumin goes down). Moreover, CRP is about the most variable of all the proteins within an individual - changing a hundred fold during infection, which is why it is such as useful test. A slight shift with recumbency would be on the cards. There is also the possibility that people with more responsive CRP (the people who go up to 200 rather than 40) are more likely to develop ME/CFS for reasons that have nothing to do with CRP itself. These may all sound obscure explanations but if ME/CFS actually involved inflammation as a main mediator of symptoms the difference would be much much bigger. Levels in ME/CFS would be five times normal.
It doesn't. It is just that the ordinary test is too crude to measure the tiny constant shift in CRP that indicates a risk of heart disease in healthy-looking people. People with risk of heart disease have a slightly higher level even when they are well.
Throughout testing early on in my illness and in some routine more recently all < 1 mg/L. Even when being really rather quite ill.
I was able to find 5 results for CRP. 2002 very severe ME: it just said <3mg/l 2012 severe ME: 1mg/l 2022 moderate ME: 37 (I had a urinary infection when this was taken) 2023 moderate ME: 1mg/l 2024 moderate ME: 2mg/l (Could be due to some throat/thyroid problems this year?) Looking back through my GP notes I have had a lot of tests for CRP but couldn't see the results for many of them.
Only 2 tests 7 years apart 10 and 14.6 mg/l. Notably I’m seriously overweight so that’s likely to be contributing
Somehow even though I’ve had dozens of bloodtests over the past couple years only a single one measured CRP. And it was the tiny level of >0.3 mg/dl. Note that I was very mild back when this test was done and even though I got PEM, only aerobic exercise or partying would trigger it. And suprisingly all my creatine markers were way over range in that test. I don’t know if that’s a common thing in ME, or maybe it’s because I was doing graded exercise.
Mine were only tested once in 2001 when I was at my worst relapse from taking immunomodulators. I was preparing to test for the hypercoagulation theory for CFS My homocysteine and CRP were all in the lower normal range.
I didn't check the box because I can't find my CRP values but from memory it was low. Homocysteine was at 5.4 (ref range 5-15)
