Objective Poor medical adherence has been reported to be associated with several negative outcomes in systemic lupus erythematosus (SLE) patients, such as increased disease activity and damage accrual. However, the predictive factors of medical adherence have been only scarcely been evaluated overall, and particularly in Latin American populations.

Methods One hundred and twenty-four patients who were taken at least one medication, and who had at least two visits between October 2022 and September 2023, members of the Almenara Lupus Cohort were included. Medical adherence was ascertained using the Compliance Questionnaire on Rheumatology (CQR); it ranges from 0 to 100 and higher scores indicate better adherence. Potential predictive factors of medical adherence were gender, age at diagnosis, educational level (in years), socioeconomic status, disease duration, PROMIS general self-efficacy, PROMIS self-efficacy for managing chronic conditions, depressive symptoms (ascertained with the PHQ9), anxiety (ascertained with the GAD7), health-related quality of life (Physical and Mental Component Summary of the SF-36), Carlson comorbidity index, disease activity (ascertained with the SLEDAI-2K), damage (ascertained with the SLICC/ACR damage index, SDI), prednisone daily dose, antimalarial e immunosuppressive drugs use, number of drugs currently used. Generalized estimated equations were done; all potential predictive factors were ascertained at the first visit as well as the CQR; the outcome was the CQR in the subsequent visit. A multivariable model was done using a backward selection procedure with an alpha to stay in the model of 0.05.

Results 293 visits from 124 patients were included, 116 (93.5%) were women with a mean age at diagnosis of 35.2 (12.6) years. Mean CQR at baseline was 75.9 (13.6) and at the end of follow-up was 76.4 (12.4). In the multivariable model, male gender, a higher educational level, disease activity and daily prednisone dose as well as previous medical adherence are predictive of better medical adherence (table 1).

Conclusions Male gender, higher educational level, disease activity, daily prednisone dose and previous medical adherence are predictive of better medical adherence. Further studies are needed to define the best strategies to improve medical adherence in SLE patients.