Prevalence and determinants of completing primary COVID-19 vaccination series among cancer patients in China: a multicentre cross-sectional survey (Preprint)

BACKGROUND Cancer patients have higher risk of contracting COVID-19 and are more vulnerable to severe consequences of COVID-19 infection. COVID-19 vaccination is effective for cancer patients without safety concerns. However, COVID-19 vaccination hesitancy is common among cancer patients. OBJECTIVE This study investigated the prevalence of completing primary COVID-19 vaccination series among cancer patients in China. We examined the effects of sociodemographic data, characteristics of cancer and treatment, and factors at individual level (perceptions) and interpersonal level (media influence). METHODS A multicentre cross-sectional study was conducted in four Chinese cities (Changzhi, Hohhot, Urumqi, and Shenzhen) in different geographic regions between May and June 2022. Medical staff of the collaborative hospitals invited all cancer inpatients aged 18 years or above without lymphoma or leukaemia to complete a face-to-face survey. A total of 893 provided written informed consent and completed the study. Logistic regression models were fitted. RESULTS Among the participants, 58.8% completed the primary COVID-19 vaccination series. Among vaccinated participants, 13.8% reported some side effects. The most common side effect was pain in the injection site (9.3%); no severe side effects were reported. After adjusting for significant background characteristics, perceived higher risk of COVID-19 infection comparing to people without cancers (adjusted odds ratios [AOR]: 0.46, 95%CI: 0.24, 0.88), perceived a high chance of having severe consequences of COVID-19 infection (AOR: 0.68, 95%CI: 0.51, 0.91), and concerns about interactions between COVID-19 vaccination and cancers/cancer treatments (AOR: 0.97, 95%CI: 0.94, 0.99) were associated with lower completion of primary vaccination series. Being suggested by significant others (AOR: 1.32, 95%CI: 1.23, 1.41) and perceived higher self-efficacy to receive COVID-19 vaccination (AOR: 1.48, 95%CI: 1.31, 1.67) were positively associated with the dependent variable. CONCLUSIONS Completion rate of primary COVID-19 vaccination series was low among Chinese cancer patients. Given the large population size and their vulnerability, there is an urgent need to increase COVID-19 vaccination coverage in this group. Removing concerns about interactions between COVID-19 vaccination and cancers/cancer treatments, using fear appeal approach, involving significant others, and facilitating patients to make a plan to receive COVID-19 vaccination might be useful strategies.