Temporal trends in glucocorticoids and hydroxychloroquine for treatment of systemic lupus erythematosus in Sweden

Abstract

Objectives: It is unknown to what extent updated treatment recommendations regarding glucocorticoids (GC) and hydroxychloroquine (HCQ) for patients with systemic lupus erythematosus (SLE) have been incorporated into clinical practice. Based on filled dispensations we examined treatment patterns the first 5 years after SLE diagnosis in Sweden, trends over time and relationship to patient characteristics.

Methods: A cohort of patients with newly diagnosed SLE between 2005 and 2021 with information on drug dispensations, hospitalizations, specialized outpatient visits and patient characteristics were identified through a linkage of Swedish population registers (n = 3891, 83% females, mean age 48.8). Treatment patterns, including accumulated exposure to GC and HCQ and combinations of treatments, were investigated in relation to year of diagnosis and patient characteristics using visualizations, logistic regression and quantile regression analysis.

Results: The proportion of SLE patients treated with GC during the first year after diagnosis was 68.3% over the study period. For the fifth year it decreased from 54.1% to 46.3%. The median decrease in 5-year cumulative GC dose attributable to calendar year was 753 mg (90% CI: 1560 mg decrease, 106 mg increase) with a more pronounced trend towards fewer patients on the highest exposure levels. The median increase in proportion of days covered with HCQ during 5 years was 28.6% (90% CI: 21.9%, 36.2%).

Conclusion: The modest reduction of GC exposure and substantial increase in HCQ coverage over time aligns with changes in recommendations for SLE management. However, treatment optimization and continued efforts to raise awareness remain essential to ensure equal care and improve clinical outcomes.

Keywords: glucocorticoids; hydroxychloroquine; systemic lupus erythematosus.

Graphical abstract showing the study results that glucocorticoid use has decreased over time but remains high, while hydroxychloroquine initiation and coverage have increased substantially over the study period.

Figure 1.

Average daily dose of glucocorticoids (GC; prednisolone equivalent; A), and hydroxychloroquine proportion of days covered (HCQ; B) during each of the first 5 years after SLE diagnosis

Figure 2.

Cumulative dose of glucocorticoid (GC; A) and hydroxychloroquine (HCQ; B), over the first 5 years after SLE diagnosis over calendar time

Figure 3.

Results from quantile regression of cumulative glucocorticoid (GC) dose (A and B), and hydroxychloroquine (HCQ) proportion of days covered (PDC; C and D), over the first 5 years after SLE diagnosis. The difference on the y-axis for each percentile of the distribution of 5-year exposure on the x-axis is the estimated difference attributable to year of diagnosis (adjusted for sex, age, educational level, country of birth, hospital where receiving the SLE diagnosis, and health care utilization). It should be interpreted in relation to the 5-year exposure distribution in the reference cohort with SLE diagnosis 2005–2008. For example, the decrease in median (50th percentile) for the 2013–2016 cohort of 753 mg (B) should be compared with the median 5-year exposure of 7500 mg in the reference cohort with diagnosis in 2005–2008. The increase in median HCQ coverage of 28.6% of days (D) should be compared with HCQ 5-year coverage of 50.2% in the reference cohort