Is PMR a form of vasculitis?

@kspowell, PMR does seem to be that disease with mystery causes which is why I think it's often misdiagnosed, just my non medical opinion. Here's some information that talks about the topic.

"Is polymyalgia rheumatica a vasculitis?
The exact cause of PMR is unknown. Like vasculitis, it is thought to be an autoimmune disorder, a disease which occurs when the body's natural defense system mistakenly attacks healthy tissue."
-- Polymyalgia Rheumatica - Vasculitis Foundation: https://www.vasculitisfoundation.org/education/forms/polymyalgia-rheumatica/

"Is polymyalgia rheumatica a large vessel vasculitis?
Therefore, PMR is thought to belong to a disease spectrum that includes GCA, large vessel vasculitis and PMR [2]. In addition, other conditions, such as neoplasia, bacterial endocarditis, osteomyelitis and other inflammatory conditions, can masquerade as PMR, which can make it difficult to ascertain the diagnosis [3]."
-- Polymyalgia rheumatica and large vessel vasculitis: a case report: https://academic.oup.com/rheumap/article/4/2/rkaa049/5932453

John - thank you . It appears there's no consensus and the question may remain unanswered: If I have PMR do I have vasculitis?
Certainly I found this direction interesting in one of the articles: "The attending clinician should always screen for large cranial and extracranial vessel vasculitis as part of the polymyalgic syndrome, especially in patients who present with strong constitutional symptoms. This can require additional tests, such as vascular US or a PET-CT scan for large vessel GCA."
Given that there are so many different presentations of GCA (and who knows of systemic vasculitis doesn't cause of other vascular or heart related problems.) Don't know about others experience, but my rheumi is only focused on Prednisone and ramping down.... doesn't even acknowledge the systemic effects of PMR.

I think it's great that you are asking questions and researching all of the possibilities. There is certainly a lot that is not known on the different connections and causes of PMR.

I asked my dr about this. He said that PMR causes the facia of the muscles to become inflamed. That inflammation can cause restriction in the vascular system but it’s not really vasculitis itself.

This article says PMR is a disease of inflammation of the musculotendinous structures (see diagram in article).

@kspowell -Your final sentence in this post really resonated with me. I have similar feelings about my rheumi. I have had PMR for about one year and first presented with an extremely elevated CRP of 165. I could understand the focus in reducing that number and the steroid treatment has been successful. My CRP has been normal since last fall and we are tapering off the steroid. So, the pain is controlled but I still have symptoms which seem to come in waves and dissipate in a day or so. The symptoms include extreme fatigue, loss of appetite and body temp regulation, tingling of skin (particularly the scalp), some pain in the pelvis area, and increased morning stiffness. I characterized this as a flare and fully expected my CRP to be elevated but it was not. So I asked the doctor if these PMR symptoms w/o CRP elevation were normal but she would not engage the question.

This section from the on line text "UptoDate" might help and the abstracts of the relevant references are included below.
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Section - Clinical manifestations and diagnosis of polymyalgia rheumatica

“PET scanning has demonstrated underlying vascular involvement in a subset of patients with PMR. Increased fluorodeoxyglucose (FDG) vascular uptake compatible with vasculitis on PET scan has been reported in approximately one-third of consecutive patients with a new diagnosis of PMR [37]. In most patients, vascular uptake was seen in the subclavian arteries, but uptake intensity was less intense than that observed in GCA [37].

The practical implications of subclinical inflammation of the great vessels in PMR is unclear, and further studies are needed to determine whether the findings on PET scanning are of prognostic or therapeutic consequence [38]. It is unusual for patients with PMR without clinical features of GCA (ie, "pure" PMR) to develop severe cranial ischemic complications such as blindness and stroke at diagnosis and large vessel stenoses or aneurysms during follow-up [39]. However, close observation should be maintained over the entire course of the disease, since typical features of cranial GCA, including ischemic events, may develop during follow-up in these patients [40]. Furthermore, isolated aortitis has been occasionally found at aneurysm surgery in patients with a history of "pure" PMR [41]. Although in our clinical practice we do not treat patients with "pure" PMR who are found to have asymptomatic large vessel involvement on imaging with the higher dose of prednisone used for GCA, and we do not recommend imaging follow-up, this is a controversial area, since patients with PMR and large vessel involvement were included in GCA clinical trials and treated as GCA [42]. However, evidence that higher prednisone doses are able to prevent the development of vascular damage, in particular of the ascending aorta aneurysm, and of late cranial GCA is lacking.”

37
PubMed
TI
Repetitive 18-fluorodeoxyglucose positron emission tomography in isolated polymyalgia rheumatica: a prospective study in 35 patients.
AU
Blockmans D, De Ceuninck L, Vanderschueren S, Knockaert D, Mortelmans L, Bobbaers H
SO
Rheumatology (Oxford). 2007;46(4):672. Epub 2006 Nov 18.

OBJECTIVE

To study fluorodeoxyglucose (FDG) deposition in different vascular beds and in the large joints of patients with isolated polymyalgia rheumatica (PMR), and to investigate whether there is a relation between FDG-positron emission tomography (PET) results and risk of relapse.

METHODS

All consecutive patients with isolated PMR underwent a FDG-PET scan before treatment with steroids was started and--if logistics allowed--at 3 and 6 months. PET scans were scored at seven different vascular areas and a total vascular score (TVS) was calculated, ranging from 0 to 21. FDG uptake in the shoulders, the hips and the processi spinosi of the vertebrae was scored as 0 (no uptake), 1 (moderate uptake) or 2 (intense uptake).

RESULTS

Thirty-five patients entered the study. At diagnosis, vascular FDG uptake was noted in 11 patients (31%), predominantly at the subclavian arteries. Mean TVS was low. FDG uptake in the shoulders was noted in 94% of patients, in the hips in89% and in the processi spinosi of the vertebrae in 51%. The intensity of FDG uptake in the large vessels or in the shoulders, hips or processi spinosi did not correlate with the risk of relapse.

CONCLUSIONS

Only one in three patients has an (moderately) increased vascular FDG uptake, especially in the subclavian arteries. The vast majority has inflammation of shoulders and hips, and half of them have increased FDG-uptake at the processi spinosi. Results of FDG-PET scans in patients with PMR did not correlate with their risk of relapse.

38
PubMed
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Polymyalgia Rheumatica and Giant Cell Arteritis: A Systematic Review.
AU
Buttgereit F, Dejaco C, Matteson EL, Dasgupta B
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JAMA. 2016 Jun;315(22):2442-58.

IMPORTANCE

Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) are related inflammatory disorders occurring in persons aged 50 years and older. Diagnostic and therapeutic approaches are heterogeneous in clinical practice.
OBJECTIVE

To summarize current evidence regarding optimal methods for diagnosing and treating PMR and GCA.

EVIDENCE REVIEWMEDLINE, EMBASE, and Cochrane databases were searched from their inception dates to March 30, 2016. Screening by 2 authors resulted in 6626 abstracts, of which 50 articles met the inclusion criteria. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool or American College of Cardiology Foundation/American Heart Association methodology.

FINDINGS

Twenty randomized clinical trials for therapy (n = 1016 participants) and 30 imaging studies for diagnosis and/or assessing response to therapy (n = 2080 participants) were included. The diagnosis of PMR is based on clinical features such as new-onset bilateral shoulder pain, including subdeltoid bursitis, muscle or joint stiffness, and functional impairment. Headache and visual disturbances including loss of vision are characteristic of GCA. Constitutional symptoms and elevated inflammatory markers (>90%) are common in both diseases. Ultrasound imaging enables detection of bilateral subdeltoid bursitis in 69% of PMR patients. In GCA, temporal artery biopsy remains the standard for definitive diagnosis. Ultrasound and magnetic resonance imaging (MRI) of large vessels revealing inflammation-induced wall thickening support the diagnosis of GCA (specificity 78%-100% for ultrasound and 73%-97% for MRI). Glucocorticoids remain the primary treatment, but the optimal initial dose and tapering treatment regimens are unknown. According to consensus-based recommendations, initial therapy for PMR is prednisone, 12.5 to 25 mg/day or equivalent, and 40 to 60 mg/day for GCA, followed by individualized tapering regimens in both diseases. Adjunctive methotrexate may reduce cumulative glucocorticoid dosage by 20% to 44% and relapses by 36% to 54% in both PMR and GCA. Use of tocilizumab as additional treatment with prednisone showed a 2- to 4-fold increase in remission rates of GCA in a randomized clinical trial (N = 30).

CONCLUSIONS AND RELEVANCE

Diagnosis of PMR/GCA is made by clinical features and elevated inflammatory markers. In PMR, ultrasound imaging may improve diagnostic accuracy. In GCA, temporal artery biopsy may not be required in patients with typical disease features accompanied by characteristic ultrasound or MRI findings. Consensus-based recommendations suggest glucocorticoids as the most effective therapy for PMR/GCA. Methotrexate may be added to glucocorticoids in patients at risk for relapse and in those with glucocorticoid-related adverse effects or need for prolonged glucocorticoid therapy.

WOW - this is great and I need to take some time to read and digest.

Hi @aliceoleary, I had PMR untreated for a number of months, then started with a tender scalp, short stabbing pains in my face from the ear to the nose, lack of appetite, fatigue, which was anemia, an itchy toso, a dry cough, and a stiff sore neck with pains up the back of my head. I couldn't turn my head. I also got shingles even though I'd had the Shingrex vaccine a year prior and had difficulty seeing out of my right eye a couple of times. I had a temporal artery biopsy which was positive for Giant Cell Arteritis. It is treated with a higher dosage of Prednisone than PMR and can result in stroke and blindness if left untreated. I'm down to 4 mg of Prednisone now from 40 mg and also take a baby aspirin as people with GCA can be prone to aortic aneurysms. It's important to watch any symptoms that occur in the head or eyes for GCA.

Thanks for posting this. All along I've been uncomfortable with the idea that PMR primarily affects the shoulder and hip joint area. When the disease was at its worst, my whole body was affected: cramping and inability to move after sitting, leg pain with walking, sudden stabbing pains in thighs, upper arms, upper back. These symptoms seemed very different from ones that would be caused by referred pain from bursa or tendons at a joint. I don't know what pain caused by vasculitis would feel like, but it makes more sense to me that muscles and tendons all over the body are affected.