Latest Research Studies into PMR and GCA

After many years in the shadows, polymyalgia rheumatica  (PMR) and giant cell arteritis (GCA) are at last coming into the spotlight of research interest among rheumatologists and other scientists.  It is part of the mission of PMRGCAuk to encourage more research into both PMR and GCA because there is still more gap than there is research-based knowledge about these conditions.  There is so much we still need to learn about what causes these illnesses, what is happening in the body and what treatments are appropriate.  That is before we even start thinking about prevention or cure.

We will update these pages with recent research and will continue to archive older papers, which you will be able to access very soon.

Incidence Trends and Mortality of Giant Cell Arteritis in Southern Norway

FEATURED PAPER APRIL 2021

Authors: Jintana B Andersen, Geirmund Myklebust, Glenn Haugeberg, Are H Pripp, Andreas P Diamantopoulos

Journal: Arthritis Care Res (Hoboken)
Date of publication: March 2021
Digital Object Identifier: https://doi.org/10.1002/acr.24133

Description of the research
The question
Is the frequency of GCA rising in Southern Norway)?
Does GCA cause a greater risk of death?

How did they approach the problem?
The authors looked into the records of a hospital serving two counties to find the number of people who were diagnosed as having GCA over a period of 14 years.  They compared their numbers with publicly available information about the population of those counties.

What did they find?
206 people had been diagnosed over 14 years with having GCA. The female to male ratio was 2.5:1.  The mean age was 73.  The annual incidence (frequency of occurrence) was calculated to be 16:8 per 100,000 people over the age of 50.  The peak decade of incidence was 70-79 years of age.  No one below the age of 50 had been diagnosed as having GCA.

The risk of death was no different to the population but was higher in men with GCA than women with GCA.  The incidence of GCA does not appear to be rising when compared to previous decades going back to the 1970’s.

Limitations of the study
This was a study that asked a narrow question and often those studies are the best studies because they are focussed.  One could argue that this does not mean much for the UK, but since almost all those who get GCA have Scandinavian or Northern European genes, this does matter.

Take-away messages
GCA is not rising in its frequency.
It is rare affecting about 17 out of every 100,000 people over the age of 50.
It does not increase the risk of death, but men do worse than women (which is true for the general population as well).

Diagnostic value of axillary artery ultrasound in patients with suspected giant cell arteritis

FEATURED PAPER MARCH 2021

Authors: Hilde Hop, Douwe J Mulder, Maria Sandovici, Andor W J M Glaudemans, Arie M van Roon, Riemer H, J A Slart, and Elisabeth Brouwer

Journal: Rheumatology (Oxford)
Date of publication: December 2020
Digital Object Identifier: https://doi.org/10.1093/rheumatology/keaa102

Description of the research
The question
What is the role of ultrasonography scanning of the axillary artery (the main blood vessel supplying the arm) in addition to the superficial temporal artery in individuals suspected of having GCA?

How did they approach the problem?
They looked at individuals who underwent ultrasonography scanning in their hospital when they were suspected of having GCA.  Since 2013, routine protocol has dictated that they scan the superficial temporal artery and the axillary artery.  A simple analysis of how many they would have diagnosed with just scanning the superficial temporal artery and how many more were picked up using axillary artery ultrasonography was carried out.

What did they find?
Of 113 individuals referred, 41 were found to be suffering with GCA. 21 (51%) had an abnormal ultrasound scan of the superficial temporal artery.  A further 8 (20%) were diagnosed because of an abnormal axillary artery ultrasonography image.

Limitations of the study
It was a retrospective study, so the flow of the cases was not built to answer the specific question.  Having appreciated that, the real-life experience outside of a ‘study’ might mean that it is more generally applicable. 

In their hospital they use dedicated sonographers who simply look at the images and report them. Arguably, if the doctors had scanned the patients after their physical examination, they might have achieved better results (sonographers interpret the images based on strict cut-off values.  This is usually the correct thing to do.  But currently there are no agreed cut-off values on the size of the abnormality.  So that interpretation requires the addition of clinical judgement of the doctor.  For example, if it was decided that a freckle can only be called a freckle if it is above a certain size, then a number of technicians who diligently measure the freckle sized would decide that there were considerably fewer freckles.  However, the rest of us would have no trouble in seeing a freckle and calling it such.  In this case, there are agreed definitions for what the abnormality should look like but not how big it should be).

Take-away messages
• Giant cell arteritis affects blood vessels beyond the superficial temporal artery and often may not involve them at all.  Thus, the phrase ‘temporal arteritis’ is a misnomer.
• If the diagnosis of GCA is suspected, a normal ultrasound scan of the temporal arteries must lead to further scanning of other blood vessels starting with the axillary arteries.

Risk factors for severe cranial ischaemic complications in giant cell arteritis

FEATURED PAPER FEBRUARY 2021

Authors: Alojzija Hočevar, Rok Ješe, Matija Tomšič, Žiga Rotar

Journal: Rheumatology (Oxford)
Date of publication: October 2020
Digital Object Identifier: https://doi.org/10.1093/rheumatology/keaa058

Description of the research
The question: What are the risk factors for visual loss and stroke in individuals with GCA?

How did they approach the problem?
The authors studied individuals diagnosed with GCA who had been examined and investigated in a structured manner. They were divided into two groups – those with stroke and/or visual involvement AND those without. All of them were treated as per the European recommendations from 2009.

What did they find?
They identified 295 new instances of GCA. 61 of them had suffered stroke or visual involvement. 52 had visual involvement including 22 who had blindness (3 suffered blindness in both eyes), 5 had strokes and 4 suffered both visual involvement and a stroke.
Those above the age of 75 years at diagnosis, smokers and those presenting with jaw pain on chewing were most likely to suffer a severe complication.

Limitations of the study
This study is from a single centre and that can sometimes lead to biases in the way that diagnosis is made. For example, those suffering a stroke might be looked after at a different place in that city and that might artificially reduce the numbers of individuals thought to suffer with complications. Secondly, causality is not fully established. In this study if a complication happened within 1 month of the diagnosis, it was attributed to GCA. We know that high doses of steroids can be a burden on the heart and provoke complications of its own.

Take-away messages
GCA is yet another disease, where smokers will do badly
• Those individuals that suffer with progressive pain on chewing at the time of diagnosis may continue to be at higher risk of suffering a complication even after starting steroids for a short period of time.
• While you can do nothing about your age, should one get GCA after the age of 75, you would be at a higher risk of suffering a complication.

An exploratory cross-sectional study of subclinical vascular damage in patients with polymyalgia rheumatica.

FEATURED PAPER JANUARY 2021

Authors: Rossana Scrivo , Valeria Silvestri, Francesco Ciciarello, Paola Sessa, Iolanda Rutigliano, Cristina Sestili, Giuseppe La Torre, Cristiana Barbati, Alessio Altobelli, Cristiano Alessandri, Fulvia Ceccarelli, Manuela Di Franco, Roberta Priori, Valeria Riccieri, Antonio Sili Scavalli, Francesca Romana Spinelli, Luciano Agati, Francesco Fedele, Bruno Gossetti, Fabrizio Conti, Guido Valesini

Journal: Scientific Reports
Date of publication: July 2020
Digital Object Identifier: https://doi.org/10.1038/s41598-020-68215-8

Description of the research:
The question: Do people with PMR have damage to their blood vessels?

How did they approach the problem?
They measured parameters acquired by imaging techniques (thickness of the carotid artery in the neck -IMT, stiffness of the arteries – CAVI, size of the aorta in the tummy – APAD) and blood tests for chemicals (leptin, adiponectin and resistin – chemicals which may alter the body’s metabolism and inflammatory responses) secreted by body fat in people with PMR and compared them to people without PMR (but who had other major risk of cardiovascular disease – people with hypertension, diabetes, high cholesterol, obesity and cigarette smokers).

What did they find?
They recruited 48 individuals with PMR and 56 with controls with major cardiovascular risk factors. The only meaningful difference between the two groups was the exposure to prednisolone. The individuals with PMR had been treated with an average 7 mg of prednisolone for over 28 months. All three measurements acquired by imaging techniques were meaningfully worse in individuals with PMR and two of the three chemical levels (leptin and adiponectin) were also higher in individuals with PMR.

Limitations of the study
• They diagnosed PMR using a criteria formulated in 2012. Since then, there have been some publications that a number of people with PMR may also have had GCA to begin with. So it is possible that some of their PMR group may have had GCA. Nevertheless, the findings are significant.
• The difference in prednisolone exposure may mean that the findings are a result of prednisolone exposure rather than because of PMR. But since one goes with the other, the findings are still meaningful.

Take-away messages
• Individuals with PMR also have damage to their arteries (perhaps because some of them may also have GCA that is unrecognised).
• This sets the ball rolling for future studies to look at the need for greater vigilance for events like heart attacks and strokes in individuals suffering with PMR.

Prevalence of Giant Cell Arteritis Relapse in Patients Treated with Glucocorticoids: A Meta‐Analysis.

FEATURED PAPER DECEMBER 2020

Authors: Sabine Mainbourg, Alexandra Addario, Maxime Samson, Xavier Puéchal, Mathilde François, Stéphane Durupt, François Gueyffier, Michel Cucherat, Isabelle Durieu, Quitterie Reynaud, Jean‐Christophe Lega

Journal: Arthritis Care & Research
Date of publication: June 2020
Digital Object Identifier: https://doi.org/10.1002/acr.23901

Description of the research:
The question: What is the relapse rate in patients with GCA treated with steroids alone?

How did they approach the problem?
They searched a medical literature database (Medline) to identify all relevant research up to December 2017. All identified literature was studied and included in their analysis if it had information about patients with GCA who were treated just with steroids. After checking the quality of the studies, the researchers pooled the data from the various small studies to make one large study.

What did they find?
The researchers found 300 studies, of which 34 studies (which included 2505 participants) had looked at this problem. The relapse rate was 47.2%. The relapse rate was higher (65.8%) in studies that attempted steroid withdrawal before 12 months, when compared to those studies that planned to use the steroids for longer (relapse rate 34.5%).

Limitations of the study
• The way that GCA was diagnosed and relapse was confirmed differed in the various studies, which may have affected the result.
• The nature of the relapses (minor shoulder pains versus full blown GCA) was not differentiated.

Take-away messages
• About half of all sufferers with GCA are likely to have a relapse at some point
• Rapid taper of steroids increases the likelihood of relapse