RESUMEN
OBJECTIVE: The objective of this study was to investigate the effect of tumor necrosis factor α inhibitor (TNFi) initiation on the use of antimicrobials among biologic-naïve patients with rheumatoid arthritis (RA). METHODS: Information on all biologic-naïve patients with RA was extracted from ICEBIO, a nationwide registry. Each patient was matched on age, sex, and calendar time to five randomly selected individuals from the general population. All filled antimicrobial and glucocorticoid prescriptions in the 2 years before and after initiation of the first TNFi were extracted from the Prescription Medicines Register. Prescriptions were quantified by using the number of filled prescriptions (NP) and defined daily doses. RESULTS: We extracted information on 359 patients with RA and 1795 comparators. During the 24 months before initiating treatment with TNFi, patients with RA received more prescriptions for antimicrobials than their matched general population comparators (mean ± SD: 2.8 ± 3.4 vs 1.6 ± 2.7; P < 0.001). The 24-month mean NP for patients with RA increased to 3.5 ± 3.9 (P < 0.001) after initiating TNFi: antibiotics, 2.6 ± 3.2 to 3.2 ± 3.5 (P < 0.001); antivirals, 0.06 ± 0.5 to 0.16 ± 0.7 (P = 0.004); and antimycotics, 0.14 ± 0.5 to 0.22 ± 0.9 (P = 0.06). The 12-month mean NP was highest in the second year after TNFi initiation (1.9 ± 2.4). No association was found between NP and glucocorticoids, age, body mass index, or pre-TNFi Disease Activity Score 28-joint count and C-reactive protein. CONCLUSION: Patients with RA on TNFi are more commonly treated for infections in the outpatient settings than previously reported. Patients are prescribed more antimicrobials in the 2 years preceding TNFi initiation than the general population, and this use further increases after initiation of TNFi. In contrast to what is reported for infections requiring hospitalization, outpatient antimicrobial use remained elevated for at least 2 years.
RESUMEN
Multiple myeloma (MM) patients have increased risk of severe coronavirus disease 2019 (COVID-19) when infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Monoclonal gammopathy of undetermined significance (MGUS), the precursor of MM has been associated with immune dysfunction which may lead to severe COVID-19. No systematic data have been published on COVID-19 in individuals with MGUS. We conducted a large population-based cohort study evaluating the risk of SARS-CoV-2 infection and severe COVID-19 among individuals with MGUS. We included 75,422 Icelanders born before 1976, who had been screened for MGUS in the Iceland Screens Treats or Prevents Multiple Myeloma study (iStopMM). Data on SARS-CoV-2 testing and COVID-19 severity were acquired from the Icelandic COVID-19 Study Group. Using a test-negative study design, we included 32,047 iStopMM participants who had been tested for SARS-CoV-2, of whom 1754 had MGUS. Among these participants, 1100 participants, tested positive, 65 of whom had MGUS. Severe COVID-19 developed in 230 participants, including 16 with MGUS. MGUS was not associated with SARS-CoV-2 infection (Odds ratio (OR): 1.05; 95% confidence interval (CI): 0.81-1.36; p = 0.72) or severe COVID-19 (OR: 0.99; 95%CI: 0.52-1.91; p = 0.99). These findings indicate that MGUS does not affect the susceptibility to SARS-CoV-2 or the severity of COVID-19.