A ‘very provocative conclusion’
That’s “a very provocative conclusion” commented Robert Landewé, MD, PhD, of Amsterdam University Medical Center who chaired the sessions. “You can see it by the [number] of people that want to ask questions.”
Dr. Robert Landewé
Désirée van der Heijde, MD, PhD, of Leiden (the Netherlands) University Medical Center, commented these data were “timely as we are updating the ASAS/EULAR [Assessment of SpondyloArthritis international Society/European Alliance of Associations for Rheumatology] recommendations at the moment.” She queried, however, if the differences were clinically significant.
“I think if you have a database of 24,000 patients, highly, statistically significant doesn’t tell me a lot. So, I want to look at the clinical meaning of the differences. So, if you have a 2% difference in retention rate, is that worth prescribing comedication?” Dr. van der Heijde said.
“I think you’re absolutely right,” Dr. Nissen responded. “We’re obviously going to find highly significant differences with such a big patient group.” While the small statistical differences seen may not look very clinically relevant at face value, they could provide some guidance for clinical decision making.
“It may alter our approach if that patient is already on a csDMARD and has peripheral disease; perhaps there’s tendency to then to keep that csDMARD rather than then stopping it and switching to a biologic agent,” Dr. Nissen argued. It’s a topic that has been debated for some time, he added, and further study is needed, but “I think it helps give a little bit more clarity to the idea.”
Dr. Désirée van der Heijde
Another point of discussion was the proportion of patients who had “pure axial disease.” More patients in the comedication group had peripheral disease, Dr. van der Heijde pointed out, “that’s also where we expect to see the differences.”
Further research is needed, but there doesn’t seem to be any impact in terms of the effect on retention, Dr. Nissen said, “but it’s a little bit harder to interpret for efficacy.”
Confounding by indication was another issued raised, which “is very difficult to control for in this type of study,” Dr. Nissen said.
“The hope is that you have a big enough population” so this doesn’t matter, but as is the nature there were lots of missing data that would have been useful to have and adjust for, such as psoriasis and smoking status. There was also no adjustment for the number of patient visits, as it’s very different from registry to registry.
Dr. Nissen disclosed grant/research support from AbbVie and Novartis. He also acknowledged acting as a consultant or speaker for AbbVie, Celgene, Janssen, Eli Lilly, Novartis, and Pfizer.