Experts share their perspectives on the preliminary results
Michael M. Kheir, MD, assistant professor of orthopedic surgery at the University of Michigan Health System, who was not involved in the studies, said he would like to see further related research.
“Perhaps steroid injections are not as benign as they once seemed,” he added. “They should be reserved for patients who already have significant arthritis and are seeking temporary relief prior to surgical reconstruction with a joint replacement, or for patients with recalcitrant pain after having already tried HA injections.”
William A. Jiranek, MD, professor and orthopedic surgeon at Duke Health in Morrisville, N.C., who also was not involved in the studies, was not surprised by the findings.
“It is important to do these studies to learn that steroid injections do not come with zero cost,” he said.
“I am pretty sure that a percentage of these patients had no cartilage loss at all,” he added. “We need to understand which OA phenotypes are not at risk of progressive cartilage loss from steroid injections.”
Annunziato (Ned) Amendola, MD, professor and sports medicine orthopedic surgeon at Duke Health in Durham, N.C., who was also not involved in the studies, said he would like to know how injection effectiveness and activity level are related.
“If the injections were effective at relieving pain, and the patients were more active, that may have predisposed to more joint wear,” he said. “It’s like tires that last longer if you don’t abuse them.”
Shared decision-making and further research recommended
Amanda E. Nelson, MD, associate professor of medicine in the division of rheumatology, allergy, and immunology at the University of North Carolina at Chapel Hill, said: “The lack of randomization introduces potential biases around why certain therapies (CS injection, HA injection, or neither) were selected over others (such as disease severity, preference, comorbid conditions, other contraindications, etc), thus making interpretation of the findings challenging.
“The causal relationship remains in question, and questions around the efficacy of intra-articular HA in particular, and the ideal settings for intra-articular therapy in general, persist,” noted Dr. Nelson, who was also not involved in the studies. “Thus, shared decision-making between patients and their providers is essential when considering these options.”
C. Kent Kwoh, MD, professor of medicine and medical imaging at the University of Arizona and director of the University of Arizona Arthritis Center, both in Tucson, said in an interview that these types of studies are important because CS injections are common treatments for knee OA, they are recommended in treatment guidelines, and other good options are lacking.
But he pointed out that the results of these two studies need to be interpreted with caution and should not be used to decide the course of treatment.
“These data are hypothesis generating. They suggest association, but they do not show causation,” said Dr. Kwoh, who was also not involved in the studies. “Both studies are secondary analyses of data collected from the OAI, which was not specifically designed to answer the questions these studies are posing.
“The OAI was not a treatment study, and participants were seen only once a year or so. They may have had joint injections anytime from only days to around 1 year before their visit, and their levels of activity or pain just prior to or just after their joint injections were not reported,” Dr. Kwoh explained.
The reasons why patients did or did not receive a specific joint injection – including their socioeconomic status, race, access to insurance, and other confounding factors – were not assessed and may have affected the results, he added.
The fact that both studies used the same data and came to the same conclusions gives the conclusions some strength, he said, but “the gold standard to understanding causation would be a randomized, controlled trial.”
Mr. Darbandi’s research received grant support from Boeing, His c-authors, as well as all experts not involved in the studies, reported no relevant financial relationshiips. Dr. Bharadwaj did not provide conflict-of-interest and funding details. Dr. Kwoh reported membership on panels that have developed guidelines for the management of knee OA.
A version of this article first appeared on Medscape.com.