Adherence to Vaccines in Adult Patients with Immune-Mediated Inflammatory Diseases: A Two-Year Prospective Portuguese Cohort Study

Background: Patients with immune-mediated inflammatory diseases (IMIDs) treated with immunomodulatory therapy present an increased susceptibility to infections. Vaccination is a crucial element in the management of IMID patients; however, rates remain suboptimal. This study intended to clarify the adherence to prescribed vaccines. Materials and methods: This prospective cohort study included 262 consecutive adults with inflammatory bowel disease and rheumatological diseases who underwent an infectious diseases evaluation before initiating or switching immunosuppressive/biological therapy. Vaccine prescription and adherence were assessed during an infectious diseases (ID) consultation using a real-world multidisciplinary clinical project. Results: At baseline, less than 5% had all their vaccines up-to-date. More than 650 vaccines were prescribed to 250 (95.4%) patients. The most prescribed were pneumococcal and influenza vaccines, followed by hepatitis A and B vaccines. Adherence to each of the vaccines ranged from 69.1–87.3%. Complete adherence to vaccines occurred in 151 (60.4%) patients, while 190 (76%) got at least two-thirds of them. Twenty patients (8%) did not adhere to any of the vaccines. No significant differences were found in the adherence rates of patients with different sociodemographic and health-related determinants. Conclusions: ID physicians can play a role in the process of increasing vaccine prescription and adherence. However, more data on patients’ beliefs and vaccine hesitancy, along with mobilization of all health care professionals and adequate local interventions, shall be considered to improve vaccine adherence.