Variation in treatment of children hospitalized with new-onset systemic juvenile idiopathic arthritis in the United States

When to stop medication in juvenile idiopathic arthritis

PURPOSE OF REVIEW

Disease-modifying antirheumatic drugs (DMARDs) have dramatically improved patient outcomes in juvenile idiopathic arthritis (JIA). However, these medications may also result in physical, psychologic, and economic burden, which must be balanced with risk of flare off treatment. Although some children remain in remission after medication discontinuation, evidence is sparse for if, when, and how medications should be de-escalated once achieving clinically inactive disease (CID). We review the data on medication discontinuation and the role of serologic and imaging biomarkers in JIA.

RECENT FINDINGS

The literature uniformly supports early biologic DMARD initiation, although the optimal timing and strategy for medication withdrawal in patients with sustained CID remains unclear. In this review, we present the current data on flare frequency and time to flare, clinical factors associated with flare, and recapture data for each JIA category. We also summarize the current knowledge on the role of imaging and serologic biomarkers in guiding these treatment decisions.

SUMMARY

JIA is a heterogenous disease for which prospective clinical trials are needed to address the question of when, how, and in whom to withdraw medication. Research investigating the roles of serologic and imaging biomarkers may help improve the ability to ascertain which children can successfully de-escalate medications.

Researchers in rheumatology should avoid categorization of continuous predictor variables

BACKGROUND

Rheumatology researchers often categorize continuous predictor variables. We aimed to show how this practice may alter results from observational studies in rheumatology.

METHODS

We conducted and compared the results of two analyses of the association between our predictor variable (percentage change in body mass index [BMI] from baseline to four years) and two outcome variable domains of structure and pain in knee and hip osteoarthritis. These two outcome variable domains covered 26 different outcomes for knee and hip combined. In the first analysis (categorical analysis), percentage change in BMI was categorized as ≥ 5% decrease in BMI, < 5% change in BMI, and ≥ 5% increase in BMI, while in the second analysis (continuous analysis), it was left as a continuous variable. In both analyses (categorical and continuous), we used generalized estimating equations with a logistic link function to investigate the association between the percentage change in BMI and the outcomes.

RESULTS

For eight of the 26 investigated outcomes (31%), the results from the categorical analyses were different from the results from the continuous analyses. These differences were of three types: 1) for six of these eight outcomes, while the continuous analyses revealed associations in both directions (i.e., a decrease in BMI had one effect, while an increase in BMI had the opposite effect), the categorical analyses showed associations only in one direction of BMI change, not both; 2) for another one of these eight outcomes, the categorical analyses suggested an association with change in BMI, while this association was not shown in the continuous analyses (this is potentially a false positive association); 3) for the last of the eight outcomes, the continuous analyses suggested an association of change in BMI, while this association was not shown in the categorical analyses (this is potentially a false negative association).

CONCLUSIONS

Categorization of continuous predictor variables alters the results of analyses and could lead to different conclusions; therefore, researchers in rheumatology should avoid it.

Effect of first-line biologic initiation on glucocorticoid exposure in children hospitalized with new-onset systemic juvenile idiopathic arthritis: emulation of a pragmatic trial using observational data

BACKGROUND

Glucocorticoid exposure is a significant driver of morbidity in children with systemic juvenile idiopathic arthritis (sJIA). We determined the effect of early initiation of biologic therapy (IL-1 or IL-6 inhibition) on glucocorticoid exposure in hospitalized patients with new-onset sJIA.

METHODS

We emulated a pragmatic sequence of trials ("pseudo-trials") of biologic initiation in children (≤ 18 years) hospitalized with new-onset sJIA utilizing retrospective data from an administrative database from 52 tertiary care children's hospitals from 2008 to 2019. Eligibility window, treatment assignment and start of follow-up between biologic and non-biologic study arms were aligned for each pseudo-trial. Patients in the source population could meet eligibility criteria at several timepoints. Mixed-effects logistic regression was used to determine the effect of biologic initiation on in-hospital glucocorticoid exposure.

RESULTS

Four hundred sixty-eight children met eligibility criteria, of which 19% received biologic therapy without preceding or concomitant initiation of immunomodulatory medications. This proportion significantly increased over time during the study period (p <  0.01). 1451 trial subjects were included across 4 pseudo-trials with 71 assigned to the biologic arm and 1380 assigned to the non-biologic arm. After adjustment, there was a trend toward decreased odds of glucocorticoid initiation in the biologic arm compared to the non-biologic arm (OR 0.39, 95% CI [0.13, 1.15]).

CONCLUSION

Biologic initiation in children hospitalized with new-onset sJIA significantly increased over time and may be associated with reduced glucocorticoid exposure. The increasing use of first-line biologic therapy may lead to clinically relevant reductions in treatment-related adverse effects of glucocorticoid-reliant therapeutic approaches.