Publication Analysis 2007-2013
by Kathleen Gransalke, Labtimes 01/2017

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Despite encompassing 200 or so disorders, European rheumatology research is dominated by only one disease – rheumatoid arthritis. At the top, not much has changed within the last decade.

“The pain passes but the beauty remains” – so French impressionist painter Pierre-August Renoir (1841-1919) once said. He wasn’t speaking of a certain melancholy or depression, from which many artists suffer, but of rheumatoid arthritis. The disease started when Renoir was just 50 years old and he deteriorated over the following twenty eight years of his life. At first, his metacarpophalangeal joints became swollen, then, “the aggressive nature of the disease resulted in the destruction and ankylosis of his right shoulder and ruptures of several extensor tendons of fingers and wrists, leading to poor hand function (...) when he was 71. Despite these deformed hands, he continued to roll his cigarettes and, according to his grandson, produced more than 400 paintings” (BMJ, 315:1704).

Rheumatoid arthritis (RA) is an autoimmune, chronic inflammatory disorder that affects the connective tissue, lining the cavities of joints and tendon sheaths, the synovium. Nobody really knows what causes it, not even scientists, but certain factors, both genetic and environmental (smoking and obesity), seem to contribute to disease outbreak. Besides RA, rheumatologists have to deal with a wide range of other rheumatic or musculoskeletal conditions, including osteoarthritis, lupus erythematosus or Sjögren’s syndrome – the latter two also being autoimmune diseases.

Low number of specialist journals

Thus, rheumatology is far from being elaborately researched. Interesting in this context is the low number of specialist journals in this discipline, which we use to compile our nations’ ranking. Under the rheumatology tag, Scimago Journal Rank lists not more than 50 journals, focussing on rheumatological topics.

From all European nations, English rheumatologists published the most papers, reviews and proceedings papers in these expert journals, also collecting most total citations. As number two, researchers at Dutch universities put German rheumatology experts in their place, the third place. Interestingly, compared to the 2010 rheumatology publication analysis, covering research output between 1997 and 2008, the top five nations remained the same – a phenomenon that will reappear later. Israel and Finland lose most places, while Poland rises from 2 1st place in 2010 to spot 17 in 2017.

When looking at the citations-per-article ratio, a measure of research quality, we are confronted with unusual numbers. Neither Switzerland (35.8) nor Scotland (43.5), the usual suspects, take the crown but the Czech Republic (58.9) and Russia (56.3; 23rd according to total citations). This is, once again, due to the fact that rheumatology is a clinically-oriented research discipline, which produces lots of highly-cited treatment guidelines, disease classification papers and clinical trial reports, with participation of numerous hospitals and universities – and often only one author from said nation, which has a rather low overall research output (164 papers in the Czech Republic’s case).

Globally, European rheumatologists published more than twice as many papers as their US-American peers. Does this translate to citation numbers? Not really. Both categories, total citations and average citations per paper, go to the US. When it comes to citations per article, US rheumatologists are trumped by their Kiwi colleagues. Not among the top six nations, publications by New Zealand rheumatologists gathered, on average, 36.1 citations.

Let’s switch over to the hottest topics in rheumatology research, judged by the most-cited papers and reviews. As mentioned earlier, publications in this discipline have a strong clinical leaning. Thus, the top three most-cited papers in rheumatology are about treating and classifying rheumatic diseases, such as osteoarthritis ( 1st) and rheumatoid arthritis (2nd and 3rd). Renoir’s disease, rheumatoid arthritis, is also the topic of the papers in positions 4 and 5, which review the disorder’s pathogenesis.

Who are now Europe’s most-cited rheumatologists? In contrast to many other publication analyses we have done, it was fairly easy to identify rheumatology researchers. The only difficulty: not all autoimmune diseases are a case for rheumatologists. Multiple sclerosis, for instance, has mostly neurological implications and we, thus, excluded all researchers studying this autoimmune disorder. The biggest overlap of rheumatology research is with immunology – no surprise, considering the fact that many rheumatic diseases are inflammatory disorders, leading to joint pain, fatigue and weight loss.

The same elite

Also in contrast to previous rankings, our top 30 most-cited researchers looks almost identical to the one we did seven years ago. All in all, 15 researchers are ranking returners and hence, are Europe’s rheumatology elite – among them our top one, Paul Emery. On the other hand, one could argue that it must be particularly hard for young rheumatology researchers to get to the top.

Among our top 30 are also relatively many women, in high positions, such as Desiree van der Heijde (3rd) and Deborah Symmons (6th). The latter works at one hotspot of rheumatology research in Europe – the University of Manchester. Here, the British charity Arthritis Research UK splashed out core funding of £2.4m per annum over four years to “unravel the complexities of disease susceptibility and treatment outcomes”.

The most-cited papers in rheumatology research, mentioned earlier, already give us a clue about our highly-cited rheumatologists’ favourite research subject. That’s right: rheumatoid arthritis. Not less than 24 of our top 30 researchers work exclusively or primarily on this disease. The ranking’s number one, Paul Emery, is no exception. In his research, he wants to elucidate RA’s immunopathogenesis and immunotherapy. In addition, he studies spondyloarthritis, another rheumatoid inflammatory disease, which can cause the fusion of spinal vertebrae, leading to stiffness and inflexibility.

Among the researchers with RA focus are also Maxime Dougados (2nd), Desiree van der Heijde and Josef Smolen (4th). In 2014, Smolen, who also studies lupus erythematosus, received the honorary doctorate of the University of Leiden for “breathing new life into the European League Against Rheumatism (EULAR), which led to a better classification of rheumatological disorders, treatment guidelines and common European research”. A more genetic course to understand RA is taken by Jane Worthington (9th), Gerd Burmester (11th) and Wendy Thomson (20th). Lars Alfredsson checks what environmental factors can cause the disease. An example of research feeds industry and vice versa is Paul Peter Tak (7th). In 2011, he joined pharma company, GlaxoSmithKline, and is now Senior Vice President and head of the company’s Immuno-Inflammation R&D. Also, several other top 30 rheumatologists, including Tore Kvien (10th) and Ronald van Vollenhoven (23rd), have received speaking/consulting fees or research funding from pharma companies, such as Pfizer, Roche and Lilly. Georg Schett (13th) studies cytokines in RA and, last but not least, Juan Gomez-Reino (29th) tests whether adipo­kines, such as leptin, adiponectin and resistin, are meaningful bio­markers of RA and other rheumatic diseases.

Beyond rheumatoid arthritis

Although rheumatoid arthritis clearly dominates European rheumatology research, a few scientists and doctors also specialise in one of the many other disorders of the rheumatic spectrum. Yehuda Shoenfeld (14th) studies the anti-phospholipid antibody syndrome or Hughes syndrome, another autoimmune disorder, in which abnormal autoantibodies in the blood cause thrombosis and pregnancy complications. Vasculitis, or inflammation of blood vessels, might not sound like a typical rheumatology topic but vasculitis patients are often referred to nephrologists or rheumatologists for treatment. In our top 30, two scientists study certain types of vasculitis: Loïc Guillevin (19th), the Churg-Strauss syndrome and Wegener’s granulomatosis; David Jayne (26th), ANCA-associated vasculitis. All three disorders affect small and medium-sized arteries.

Covering more than 200 different diseases, ranging from auto­immune to inflammatory and wear-and-tear diseases, rheumatology will not run out of research subjects any time soon. And perhaps, it can manage something that nothing else has been able to do: raise tolerance among religions. In a 2008 paper, Paul ­Peter Tak described how Islamic prayers can help spondylo­arthritis patients regain some of their spinal mobility. “­Islamic prayers consist of several postures, including stretching, bending and kneeling,” Tak explains. Two hours daily for one month can “offer benefits, when used in conjunction with conventional treatments”


View the Tables: Europe...and the World, Most Cited Authors...and Papers

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Last Changed: 11.02.2017