Slowly tapering off – or remaining on – antimalarial medications can help prevent disease flare in patients with systemic lupus erythematosus (SLE) who’ve achieved clinical remission for at least a year, according to a new study that was presented at the virtual annual meeting of the American College of Rheumatology.
“Except in the setting of toxicity, cessation of antimalarial medication in patients with disease quiescence is feasible using a slow taper,” lead author Danaë Papachristos, MBBS, said during an oral abstract presentation at the online meeting. Papachristos conducted the research while a clinical and research fellow at the University of Toronto’s lupus clinic, but is now a consultant rheumatologist at the Wesley Hospital in Brisbane, Queensland, Australia.
To investigate flare in patients with SLE who were on or recently off antimalarial medications (AMs), the researchers identified 1,573 potential participants from a long-term observational cohort study at the university’s lupus clinic. From that larger group, 88 cases – patients who achieved clinical remission for at least a year and stopped taking AMs – were matched to at least one control – patients who also achieved remission and continued on medication. Most cases were also matched to a second control, bringing the total number to 173. All patients had at least 2 years of follow-up.
Flare was defined as any increase in the SLEDAI-2K score, with major flare defined as an increase of 4 or more. Patients in the case group were roughly 44 years old, compared with an average age of 46 in the control group. Both groups were almost entirely female and largely white. Reasons for withdrawal in the case group included self-cessation, disease quiescence, and retinal, mucocutaneous, or cardiac toxicities. Twenty participants in the case group reported AM toxicity, compared with four controls.
Papachristos noted in her presentation that the toxicity disparity was expected, “because controls are those who continue their medication, and most patients who have toxicity will stop their medication.”
Disease flare occurred in 61.4% of cases, compared with 45.1% of controls (P = .002), with the most common types being cutaneous and musculoskeletal flares. After multivariate analysis, the risk of flare more than doubled for those who ceased AMs (odds ratio, 2.26; 95% confidence interval, 1.24-4.11; P = .008). More than half of the cases (n = 46) restarted AMs after withdrawal, which was largely due to disease flare. Of the patients who restarted due to flare, 88% either recaptured control or improved, and the remaining 12% had further flares.
Of the 88 patients in the case group, 51 abruptly withdrew AMs while 37 tapered off. Patients who tapered had fewer flares (45.9%), compared with patients who withdrew abruptly (72.6%). After multivariate analysis, the risk of flare more than tripled for the abrupt withdrawal group (OR, 3.42; 95% CI, 1.26-9.26; P = .016). Fewer patients who tapered later restarted AMs, compared with the abrupt withdrawal group (37.8% vs. 62.7%; P = .02).
When asked about other differences in medications between the two groups, Papachristos answered: “We didn’t look into that specifically. We did look at those patients who were on prednisone and on any immunosuppression, although we didn’t look at specific therapies. Those variables were adjusted for in the analysis, and it didn’t make any difference if patients were on immunosuppression or prednisone at the point of index date.
“But we would like to look into the different forms of immunosuppression,” she added, “just to see if that made any difference.”
Withdrawing Hydroxychloroquine in Older Patients
Older patients with SLE who discontinue their use of hydroxychloroquine (HCQ) are also not at increased risk of disease flare, according to a retrospective chart review from rheumatologists Ruth Fernandez-Ruiz, MD, and Peter M. Izmirly, MD, of New York University (Arthritis Res Ther. 2020;22:191. doi: 10.1186/s13075-020-02282-0).
“We wanted to focus on older patients who may have a lower risk of flaring and a higher risk of side effects from the drug,” Fernandez-Ruiz said in an interview.
The doctors embarked on the study after noticing eye and heart toxicities in certain older patients. They matched 26 lupus patients who had been on HCQ for at least 5 years before discontinuing the drug with 32 control patients who remained on HCQ, ultimately finding that withdrawal had no effect on their risk of lupus flares within a year.
“After starting a drug, the second question most people ask, after ‘What are the side effects?’ is ‘How long do I have to be on this?’ ” Izmirly said in an interview. “These patients are having side effects associated with long-term HCQ use. And we were noticing that, after you stop the drug, despite what you’re taught, they weren’t flaring.”
Only five patients from each group – 19.2% of the withdrawal group and 15.6% of the continuation group – experienced a flare (OR, 1.28; 95% CI, 0.31-5.30; P = .73). Most of the flares were cutaneous and musculoskeletal in nature, and no severe flares occurred in either group.
“On each side, the overall flare rate was not that high, and they were all relatively mild,” Izmirly said.
The two doctors acknowledged their study’s smaller sample size, compared with the study by Papachristos and colleagues, along with the advanced age of their patient population, which limits the generalizability of their findings. “We selected patients who had a very low disease activity to begin with, and who were older,” Fernandez-Ruiz noted.
That said, they reinforced the scarcity of existing research on this subset of lupus patients, one that will only continue to grow.
“Older [patients with] lupus,” Izmirly said, are “an understudied demographic.”
One of the authors of the study presented at ACR 2020 acknowledged receiving research support and consulting fees from various pharmaceutical companies. The HCQ study was supported by a grant from the National Institute of Arthritis and Musculoskeletal and Skin Diseases; its authors declared no conflicts of interest.
SOURCE: Papachristos D et al. Arthritis Rheumatol. 2020;72(suppl 10). Abstract 0983.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.