In depth
Vasculitis: common questions
Twenty-three of 130 people with giant cell arteritis had a normal sedimentation rate and a normal CRP at the same time. That's the finding on this page most likely to change what happens to somebody. Almost everything else in this condition group has barely been studied at all, and this page says so plainly.
What the research found.
CRP was 74 percent sensitive and 49 percent specific for detecting giant cell arteritis in that study. The area under the curve for it was 0.675, which is modest. ESR came in at 48 percent sensitivity and 72 percent specificity, so neither of the two is the better test.
Twenty-three of 130 patients with giant cell arteritis had both a normal sedimentation rate and a normal CRP. Those measured later after symptom onset were more likely to have normal markers. The mean was 35 days against 20 days, which runs the opposite way to what most people would guess.
For all adults starting or continuing long-term glucocorticoids, the 2017 American College of Rheumatology guideline gives a strong recommendation. It asks them to optimize calcium and vitamin D intake, and to implement weight-bearing and strength-building exercise, smoking cessation, and limiting alcohol. Those four items are its own wording rather than a summary.
In 198 patients with polymyalgia rheumatica, giant cell arteritis, and other vasculitides, neither current nor cumulative glucocorticoid dose was associated with bone mineral density. What was associated with it was lower body mass index, prior vertebral fracture, and proton-pump inhibitor use. So the dose alone doesn't tell you the risk.
The 2018 EULAR physical activity recommendations judged public health activity targets applicable to people with inflammatory arthritis and osteoarthritis, which are different conditions. Systemic vasculitis is not one of the conditions they cover. So they get quoted in this area more often than they properly apply, and that's worth knowing.
Rausch Osthoff and colleagues, Annals of the Rheumatic Diseases, 2018
The finding that counts most
A 2025 study looked at how well inflammatory markers detect giant cell arteritis and produced a result worth taking into any appointment. Twenty-three of 130 patients with the disease had both a normal sedimentation rate and a normal CRP. Those 23 had it, and nothing in their blood results said so.
The accuracy figures explain how that happens. CRP was 74 percent sensitive and 49 percent specific, with an area under the curve of 0.675. ESR was 48 percent sensitive and 72 percent specific, at 0.644. A test that's only 48 percent sensitive misses more than half the cases it is asked about.
Giant cell arteritis threatens sight, and untreated it can cause sudden and permanent visual loss. That combination, a serious consequence and tests that miss cases, is why the clinical picture outranks a normal number here more clearly than anywhere else on this site. Nowhere else on this site does a normal result have the potential to cost so much.
Why the markers behave the way they do
CRP and ESR measure two quite different things, which is a large part of why they so often disagree. CRP is a protein the liver makes in response to inflammation and it moves within a day or two, while ESR measures how quickly red cells settle. That settling rate is influenced by inflammation and also by age, anemia, and pregnancy, and it moves slowly.
Their accuracy figures line up behind that difference, and neither test comes out ahead of the other overall. CRP misses fewer cases and raises more false alarms. ESR raises fewer false alarms and misses more cases. Sending both is how most clinicians handle that trade in practice, and the two results disagreeing is normal rather than a laboratory error.
One further finding in that study is counterintuitive and it's worth knowing about. Patients whose markers were measured later after symptom onset, at a mean of 35 days against 20, were more likely to have normal results, at a P value of 0.03. So a normal result late in a story offers less reassurance than the same result early, which is the opposite of what most people would guess.
What the research doesn't cover
No exercise trial exists in ANCA-associated vasculitis or EGPA. The only exercise trial in any vasculitis at all is a small study in Takayasu arteritis. Our record for it says explicitly that it should not be presented as evidence that exercise lowers vasculitis activity, and the reason lies in what the study set out to measure. What it reports are correlations between TNF-alpha and the inflammatory markers rather than a between-group effect on disease activity.
No disease-specific nutrition trial exists anywhere in vasculitis either. Steroid treatment makes weight and blood sugar worth attention for reasons anybody would accept, and that reasoning isn't a trial result in this condition. Anything offered as a vasculitis diet is drawing on other diseases or on nothing.
The 2018 European physical activity recommendations get quoted in this area without qualification, and what they cover is inflammatory arthritis and osteoarthritis rather than vasculitis. Systemic vasculitis isn't among the conditions they were written for, and this page says so rather than borrowing them silently. That distinction is easy to lose in a summary and it's worth keeping hold of.
What does apply, through the steroids
Most people with systemic vasculitis take glucocorticoids, often at substantial doses and for a long time, and that brings a guideline of its own. For all adults starting or continuing long-term glucocorticoids, the 2017 American College of Rheumatology guideline gives a strong recommendation across all age groups: optimize calcium and vitamin D intake, and implement weight-bearing and strength-building exercise, smoking cessation, and limiting alcohol. Those four items are the guideline's own wording rather than a summary of it.
That's the most specific lifestyle wording available to anyone with this diagnosis, and it comes through the treatment rather than the disease. It's also more useful than it sounds, because weight-bearing and strength-building name a kind of work rather than leaving you to guess. Most advice in rare disease doesn't get that far.
The bone picture is less predictable than most people expect. In 198 patients with polymyalgia rheumatica, giant cell arteritis, and other vasculitides, neither current nor cumulative glucocorticoid dose was associated with the minimum T-score. What was associated with lower bone density was lower body mass index, prior vertebral fracture, and proton-pump inhibitor use. That study was cross-sectional in people mostly already on bone protection, so it can't replace a trial, and it argues that your dose alone doesn't tell you your risk.
Why so little has been studied
The vasculitides are individually rare. Recruiting enough people for a properly powered exercise or nutrition trial is genuinely difficult, and the research money that exists goes to treatment, which is where the mortality is. That's the explanation rather than a judgment that these questions don't matter.
It does mean the honest answer to most lifestyle questions in this condition group is that the answer isn't known. This site would rather say that than fill the space with advice borrowed from rheumatoid arthritis and presented as though it were about vasculitis. A blank that says why it's blank tells you more than a borrowed answer does.
What remains is the same as for anyone else, plus the steroid guideline, plus one thing worth repeating. A new headache, jaw pain on chewing, scalp tenderness, or any visual symptom in someone with or suspected of having giant cell arteritis needs urgent attention rather than a routine appointment. That sentence is the most useful thing on this page.
Common misconceptions.
Myth. Normal inflammatory markers rule out giant cell arteritis.
Reality. Twenty-three of 130 patients with the disease had both a normal sedimentation rate and a normal CRP. CRP was 74 percent sensitive and ESR 48 percent, so both miss cases and ESR misses more than half. Because untreated giant cell arteritis threatens sight, a normal result is the wrong thing to be reassured by when the clinical picture fits.
Myth. A high sedimentation rate is the more reliable test.
Reality. CRP outperformed it on sensitivity, at 74 percent against 48 percent, with an area under the curve of 0.675 against 0.644. ESR was the more specific of the two, at 72 percent against 49 percent. They're measuring different things and disagreeing is normal, which is why both get sent and neither settles the question alone.
Myth. There must be exercise guidance for vasculitis.
Reality. No exercise trial exists in ANCA-associated vasculitis or EGPA, and the only exercise trial in any vasculitis is in Takayasu arteritis. Our record for that study says explicitly that it should not be presented as evidence that exercise lowers vasculitis activity, because what it reports are correlations rather than a between-group effect on disease activity. So there's no guidance here built on a trial in this condition group.
Myth. My steroid dose tells me my fracture risk.
Reality. In 198 patients with these diagnoses, neither current nor cumulative glucocorticoid dose was associated with the minimum T-score. Lower body mass index, prior vertebral fracture, and proton-pump inhibitor use were. That study was cross-sectional in people mostly already on bone protection, so it can't replace a trial, and it argues that the dose alone doesn't tell you the risk.
Questions patients ask.
Can I have giant cell arteritis with normal blood tests?
Yes, and it's the most consequential fact on this page. Twenty-three of 130 patients with the disease had both a normal sedimentation rate and a normal CRP. CRP was 74 percent sensitive and 49 percent specific with an area under the curve of 0.675, and ESR was 48 percent sensitive and 72 percent specific. Because untreated disease threatens sight, normal markers aren't the thing to be reassured by.
Why would my markers be normal if I'm unwell?
Timing appears to be part of it. Patients with a longer interval from symptom onset to measurement were more likely to have normal markers, at a mean of 35 days against 20, at a P value of 0.03. That's a counterintuitive direction and it's what the study found. The practical consequence is that a normal result late in a story doesn't offer the reassurance a normal result early might.
Which is the better test, CRP or ESR?
Neither one of them is better, because the two tests fail in opposite directions. CRP is the more sensitive of the two, at 74 percent against 48 percent, so it misses fewer of the cases. ESR is the more specific at 72 percent against 49 percent, so it produces fewer false alarms. Areas under the curve were 0.675 and 0.644, both describing tests that help rather than decide, and disagreement between them is normal rather than a laboratory error.
Is there exercise guidance for vasculitis?
Nothing specific to it. No exercise trial exists in ANCA-associated vasculitis or EGPA, and the only exercise trial in any vasculitis is a small study in Takayasu arteritis whose reported results are correlations rather than a between-group effect on disease activity. The 2018 European physical activity recommendations cover inflammatory arthritis and osteoarthritis, which are different conditions.
So should I exercise?
The glucocorticoid guideline gives the one sourced answer available. For all adults starting or continuing long-term steroids, the 2017 American College of Rheumatology guideline strongly recommends weight-bearing and strength-building exercise alongside calcium, vitamin D, stopping smoking, and limiting alcohol. That applies to anyone on long-term steroids whatever put them there, which includes most people with systemic vasculitis.
Is there a diet for vasculitis?
No disease-specific nutrition trial exists in vasculitis. Steroid treatment does make nutrition worth attention for reasons of weight and blood sugar, and that reasoning isn't a trial result in this condition. Anything offered to you as a vasculitis diet is drawing on other diseases or on nothing, and asking which is a fair question to put to whoever is offering it.
Will steroids damage my bones?
The relationship is a good deal less direct than it's usually presented. In 198 patients with polymyalgia rheumatica, giant cell arteritis, and other vasculitides, neither the current nor the cumulative glucocorticoid dose was associated with the minimum T-score. Lower body mass index, prior vertebral fracture, and proton-pump inhibitor use all were. That argues for bone protection and for weight-bearing work rather than against either of them.
Why is there so little research?
The vasculitides are individually rare, which makes recruiting enough people for a trial hard, and the research funding that exists goes to treatment rather than rehabilitation. That's a feature of rare disease research rather than a judgment that exercise or diet don't matter here. It does mean that confident advice for this diagnosis is coming from somewhere other than a study in it.
What should I take to my next appointment?
Anything new and specific. A new headache, jaw pain on chewing, scalp tenderness, or any visual symptom needs urgent attention rather than a routine mention, because sight loss in giant cell arteritis can be sudden and permanent. Beyond that, breathlessness, blood in the urine, numbness, and new rashes all matter, because this disease group affects vessels anywhere.
References.
- Currier C; Bays A; Thomason J. Normal inflammatory markers in giant cell arteritis: a diagnostic blind spot. Rheumatology International. 2025;45. 10.1007/s00296-025-05930-3Retrospective diagnostic accuracy study within a single fast-track GCA clinic
- Buckley L; Guyatt G; Fink H et al. 2017 American College of Rheumatology Guideline for the Prevention and Treatment of Glucocorticoid‐Induced Osteoporosis. Arthritis & Rheumatology. 2017;69:1521-1537. 10.1002/art.40137GRADE-based clinical practice guideline
- Palmowski A; Wiebe E; Muche B et al. Glucocorticoids Are Not Associated with Bone Mineral Density in Patients with Polymyalgia Rheumatica, Giant Cell Arteritis and Other Vasculitides—Cross-Sectional Baseline Analysis of the Prospective Rh-GIOP Cohort. Cells. 2022;11:536. 10.3390/cells11030536Cross-sectional baseline analysis of a prospective cohort
- Rausch Osthoff A; Niedermann K; Braun J et al. 2018 EULAR recommendations for physical activity in people with inflammatory arthritis and osteoarthritis. Annals of the Rheumatic Diseases. 2018;77:1251-1260. 10.1136/annrheumdis-2018-213585EULAR recommendations for physical activity in people with inflammatory arthritis and osteoarthritis
- Li G; Liu F; Wang Y et al. Effects of resistance exercise on treatment outcome and laboratory parameters of Takayasu arteritis with magnetic resonance imaging diagnosis: A randomized parallel controlled clinical trial. Clinical Cardiology. 2020;43:1273-1278. 10.1002/clc.23439Randomised parallel controlled clinical trial
This page gathers the published research on this subject into one place. The studies behind it were published between 1989 and 2026, and every figure links to the paper it came from. Those studies were peer reviewed. This summary of them was not. Dr. Sarah Luebker is reviewing these pages one at a time and has not reached this one yet, so it carries no medical review date and nothing here is her opinion or her advice to you. Each page gets updated as she reaches it. It is here in the meantime because the science is worth having in one organized place that is easy to find and easy to read. Talk to your own clinician before acting on any of it.