#1 Metabolic Syndrome-Associated OA
Metabolic derangements (i.e. the Metabolic Syndrome, but also metabolic disturbances in general) are associated with systemic inflammatory change (i.e. "meta-inflammation"). Not only does this increase cardiovascular risk, but also risk of OA, even in non-load bearing joints (e.g. hands). Metabolic syndrome-associated OA needs to be studied independently from other forms since treatment may be different from post-traumatic OA. As reviewed by Dr. Francis Berenbaum and Dr. Tonia Vincent today, "one size does not fit all" when it comes to OA phenotypes.
#2 The Pain vs. Damage Association in OA
Pain doesn't follow damage perfectly. Especially in OA. The same level of damage (by radiography, insert debate here about appropriate testing for structural changes in OA, but I will leave that for another day) will associate with a wide range of pain levels. But beyond level of pain, OA is associated with markedly variable pain phenotypes that are only starting to become clear. These include widespread pain, focal pain, pain only with weight bearing, inflammatory pain, pain associated with muscle weakness/sarcopenia, and more. We are still only beginning to understand the relationships between pain to clinical outcomes and change over time, so stay tuned. However, different phenotypes are quite likely to vary in their responsiveness to any given pain treatment (medical or non-medical). This is a hot area right now in the OA research space.
#3 Hand OA is a Major Unmet Need
Unfortunately, many RCTs for therapeutics in hand OA have failed, which probably relates at least substantially to the fundamental difference of inflammation in hand OA vs. autoimmune inflammatory arthritis. Recent trial failures have been reported for hydroxychloroquine, anti-TNFa, anti-IL-1b, and now (presented at EULAR 2017) dual anti-IL-1b/IL-1a strategies. Very early data with anti-IL-6 looks promising for at least pain and function improvement, but only in 18 patients so far. This study was presented by Dr. Sanchez-Huerta in poster form, but no imaging endpoints were included unfortunately.
There is an argument that the outcomes being measured in studies aren't quite right either. While the knee OA imaging field has progressed substantially, structural hand OA outcome measures for MRI are still in proposal stages and not widely agreed upon. Even the best treatments will fail if you don't measure them properly. Moreover, if measures aren't standardized across studies, you can't compare the results either. Important work to be done for OA of the hands, says Dr. Ruth Wittoek.
#4 Inflammation and Bony Change Points to Etiology of Symptoms in OA
An exciting new idea was presented by Dr. Ai Lyn Tan and colleagues using the MRI outcome scoring system HOAMRIS. They showed that the presence of both ligament and capsular/synovium abnormalities (e.g. fluid, synovitis, ligament thickening, ligament edema, bone edema) was present in 93% of patients with symptomatic (painful) hand OA vs. only 43% of asymptomatic hand joints. Again, inflammation and bony change seems to point to the etiology of symptoms, but we have yet to find the right mechanism to target with medications.
Adios from EULAR 2017!
Dr. Appleton completed the combined MD/PhD program at Western University in Canada and is now a rheumatologist and clinician scientist at St. Joseph’s Hospital in London, Canada. In addition to his rheumatology practice, Dr. Appleton oversees a translational biology research program in early osteoarthritis.View Full Bio