Practices and predictors of 2009 H1N1 vaccination in cancer patients: a nationwide survey in Korea

BACKGROUND Because patients with cancer are considered to be at high-risk for influenza infection and related complications, annual vaccination is recommended. The emergence of the novel H1N1 influenza virus in 2009 complicated the medical care of patients with cancer. The present study examined H1N1 vaccination practices among patients with cancer during the pandemic season and investigated factors related to the vaccination. METHODS A national multicenter cross-sectional survey of patient-doctor dyads was performed; A total of 97 oncologists (response rates of invited participants, 87.4%) and 495 patients (response rates of recruited participants, 86.5%) were included. Patients with cancer provided information concerning vaccination practices and reasons for/against it. Oncologists answered questions about their recommendations and knowledge of H1N1 vaccination. Mixed logistic regression was used to identify patient-level and physician-level predictors of H1N1 vaccination. RESULTS Only 34.1% of the patients had received H1N1 vaccination, and 53.5% had not considered the need for vaccination. The H1N1 vaccine was proactively recommended by physicians in only a small fraction of patients (8.3%). Increasing age, higher educational status, longer time since the cancer diagnosis, comorbidities, and greater knowledge of H1N1 vaccination among oncologists were significant predictors of patients being vaccinated. CONCLUSIONS The present results showed low levels of utilization and poor interaction between patients and physicians with regard to the need for vaccination. In addition, the oncologist's level of knowledge affected the adoption of preventive services. Intervention strategies are needed to maximize the rapid adoption of preventive methods to confront future pandemic threats in the cancer patient population.