January 14, 2021
2 min read
Disclosures: Curtis reports grants and personal fees from Abbvie, Amgen, Bristol Myers Squibb, Corrona, Eli Lilly & Co., Jannsen, Myriad, Pfizer, Regeneron, Roche and UCB. Please see the study for all other authors’ relevant financial disclosures.
The adjusted multibiomarker disease activity test for rheumatoid arthritis is prognostic for radio progression, and is a stronger predictor than conventional risk factors, according to data published in Arthritis Research & Therapy.
“The multibiomarker disease activity (MBDA) blood test measures 12 serum biomarkers, including CRP, to generate a score on a scale of 1-100 that represents the level of disease activity in adult patients with RA,” Jeffrey R. Curtis, MD, MS, MPH, of the University of Alabama at Birmingham, and colleagues wrote. “The MBDA score has categories of low (<30), moderate (30-44), and high (>44) disease activity. Change in MBDA score correlates with change in clinical disease activity.”
“When assessing change from a moderate or high MBDA score to a later score, the minimally important difference is 8 points,” they added. “In 2019, the MBDA score was the subject of a systematic review and meta-analysis, and the American College of Rheumatology disease activity measures working group concluded that the MBDA score was one of 11 RA disease activity measures that fulfilled the minimum standard for regular use.”
According to Curtis and colleagues, a newer version of the MBDA score, adjusted for age, sex, and adiposity, has been validated in two cohorts — OPERA and BRASS — for predicting the risk for radiographic progression in RA. To extend these findings and further validate the adjusted MBDA score as a predictor of radiographic progression risk, as well as compare it to other risk factors, the researchers analyzed a total of four cohorts. These included the previous BRASS and OPERA cohorts in addition to the Leiden registry and the SWEFOT study. In all, the cohorts include 953 patients receiving non-biologic and biologic disease-modifying antirheumatic drugs.
Jeffrey R. Curtis
Curtis and colleagues used linear and logistic regression to examine the associations of annual radiographic progress with the adjusted MBDA score, as well as with seropositivity and clinical measures. Specifically, the researchers validated the adjusted MBDA score in the Leiden and SWEFOT cohorts, and compared the score against other measures in all four cohorts. They then used the adjusted MBDA score to develop curves for predicting risk for radio progression.
According to the researchers, both univariable and bivariable analyses validated the adjusted MBDA score and found it to be “the strongest, independent predicator of radiographic progression,” compared with seropositivity, baseline radiographic progression, DAS28-CRP, CRP swollen joint count, or the Clinical Disease Activity Index (CDAI). In addition, neither the DAS28-CRP, CDAI, swollen joint count, nor CRP measures added significant information to the adjusted MBDA score as a predictor, while the frequency of radiographic progression agreed with the adjusted MBDA score even when it was discordant with the other measures.
The researchers also found that the rate of progression increased from less than2% in the low adjusted MBDA category to 16% in the high category. Additionally, a modeled risk curve demonstrated that risk increased continuously, topping 40% for the highest adjusted MBDA scores.
“We have validated the adjusted MBDA score and performed the largest combined analysis to date of it as a prognostic test for radiographic progression in RA,” Curtis and colleagues wrote. “The adjusted MBDA score was a stronger predictor of radiographic progression than DAS28-CRP, CRP, SJC, and CDAI, and its prognostic ability was not improved by any of these other measures, including when it was discordant with them.”
“A risk curve was generated to show that the risk of rapid radiographic progression approached zero when the adjusted MBDA score was low, and it increased continuously with the adjusted MBDA score, such that risk exceeded 40% and included the most severe cases of progression when the adjusted MBDA score was very high,” they added. “The results of this study validate the adjusted MBDA score as an objective, independent measure of disease activity that, without requiring information from clinical assessment, can stratify RA patients according to their risk for developing new joint damage.”