Background Various observations have suggested that the course of COVID-19 might be less favourable in patients with inflammatory rheumatic and musculoskeletal diseases receiving rituximab compared with those not receiving rituximab. We aimed to investigate whether treatment with rituximab is associated with severe COVID-19 outcomes in patients with inflammatory rheumatic and musculoskeletal diseases.Methods In this cohort study, we analysed data from the French RMD COVID-19 cohort, which included patients aged 18 years or older with inflammatory rheumatic and musculoskeletal diseases and highly suspected or confirmed COVID-19. The primary endpoint was the severity of COVID-19 in patients treated with rituximab (rituximab group) compared with patients who did not receive rituximab (no rituximab group). Severe disease was defined as that requiring admission to an intensive care unit or leading to death. Secondary objectives were to analyse deaths and duration of hospital stay. The inverse probability of treatment weighting propensity score method was used to adjust for potential confounding factors (age, sex, arterial hypertension, diabetes, smoking status, body-mass index, interstitial lung disease, cardiovascular diseases, cancer, corticosteroid use, chronic renal failure, and the underlying disease [rheumatoid arthritis vs others]). Odds ratios and hazard ratios and their 95% CIs were calculated as effect size, by dividing the two population mean differences by their SD. This study is registered with ClinicalTrials.gov, NCT04353609.

Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research. Patient consent for publication Not required. Ethics approvalThe study was approved by the institutional review board (IRB-MTP_2020_04_202000446).Provenance and peer review Not commissioned; internally peer reviewed. This article is made freely available for use in accordance with BMJ's website terms and conditions for the duration of the covid-19 pandemic or until otherwise determined by BMJ. You may use, download and print the article for any lawful, non-commercial purpose (including text and data mining) provided that all copyright notices and trade marks are retained.

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Objectives: Giant cell arteritis (GCA) is associated with severe outcomes such as infections and cardiovascular diseases. We describe here the impact of GCA patients’ characteristics and treatment exposure on the occurrence of severe outcomes. Methods: Data were collected retrospectively from real-world GCA patients with a minimum of six-months follow-up. We recorded severe outcomes and treatment exposure. In the survival analysis, we studied the predictive factors of severe outcomes occurrence, including treatment exposure (major glucocorticoids (GCs) exposure (>10 g of the cumulative dose) and tocilizumab (TCZ) exposure), as time-dependent covariates. Results: Among the 77 included patients, 26% were overweight (BMI ≥ 25 kg/m2). The mean cumulative dose of GCs was 7977 ± 4585 mg, 18 patients (23%) had a major GCs exposure, and 40 (52%) received TCZ. Over the 48-month mean follow-up period, 114 severe outcomes occurred in 77% of the patients: infections—29%, cardiovascular diseases—18%, hypertension—15%, fractural osteoporosis—8%, and deaths—6%. Baseline diabetes and overweight were predictive factors of severe outcomes onset (HR, 2.41 [1.05–5.55], p = 0.039; HR, 2.08 [1.14–3.81], p = 0.018, respectively) independently of age, sex, hypertension, and treatment exposure. Conclusion: Diabetic and overweight GCA patients constitute an at-risk group requiring tailored treatment, including vaccination. The effect of TCZ exposure on the reduction of severe outcomes was not proved here.