(037) Switching proportion assessment in rheumatoid arthritis patients exposed to disease modifying anti-rheumatic drugs: systematic review and meta-analysis

Background: The switching proportion of disease-modifying anti-rheumatic drugs (DMARDs) in rheumatoid arthritis (RA) patients showed high variability across studies and different types of users (incident and prevalent).

Objectives: To estimate the switching proportion in DMARD users for RA and to identify variables influencing the proportion.

Methods: We performed a systematic review and meta-analysis according to the PRISMA and MOOSE guidelines (PROSPERO, CRD420191387765). We included full-length original articles in English language reporting switching proportions in retrospective studies carried out on healthcare administrative databases in RA DMARDs users, published until June 11th, 2019 (to avoid Covid-19 interferences). In the main analysis, we classified users into three groups of exposure: incident, prevalent, and mixed. In the secondary analysis, among the prevalent group, we evaluated the subgroup of switchers. We performed a meta-analysis of the Freeman-Tukey Double arcsine transformation of proportions using random-effects models and stratified analyses according to the type of drugs, duration of the grace period, and follow-up duration. The Cochran Q test was used to test heterogeneity within group and between groups. P-values lower than 0.05 were considered statistically significant.

Results: We included 27 studies. Out of 174,034 users, 165,013 were exposed to biologic DMARDs, 8,619 to conventional DMARDs and 402 to targeted synthetic DMARDs and 67,072 were incident patients, (16 studies, 59 groups, mean age 53.76 ±4.31, females 70.51%) 86,921 prevalent users (14 studies, 39 groups, mean age 49.98 ±3.57, females 93.01%) and 20,041 mixed ones (4 studies,17 groups, mean age 49.83 ±3.05, females 62.90%). The pooled switching proportion was 0.1877 [0.1547; 0.2228], 0.2322 [0.1817; 0.2868], and 0.1652 [0.1103; 0.2281], respectively. All proportions were heterogeneous (I2>95%). We observed statistically significant differences between all groups (p < 0.0001) except the grace period variable in mixed users (0.4138). In the secondary analysis, 35,040 prevalent users (4 studies, 14 groups, mean age 47.96 ±4.30, females 51.27%) and 51,881 switchers were identified (11 studies, 25 groups, mean age 49.96 ±3.80, females 83.7%). The pooled proportion of switching users was 0.1347 [0.0671; 0.2207] and 0.2891 [0.2359; 0.3454], respectively. Statistically significant differences were observed between all groups (p < 0.0001) except for the follow-up in prevalent users (0.2212) and the drug in switchers (0.0707).

Conclusions: Variables such as type of drug, grace period, and follow-up duration can affect the switching proportion for incident, prevalent, and mixed users.