Background and hypothesis. The increased anxiety owing to the COVID 19 pandemic has been suggested to contribute to unhealthy lifestyles and depression in patients undergoing haemodialysis (HD). Therefore, this study aimed to evaluate the degree of fear of COVID 19 after vaccination dissemination and the independent impact of high order health literacy (HL) on fear, which have not been adequately investigated. Methods. This multicentre cross sectional study, conducted in 2022, after the widespread availability of the COVID 19 vaccination in Japan, included adults undergoing in centre HD. Multidimensional HL was measured using the 14-item Functional, Communicative, and Critical Health Literacy Scale. Fear of COVID 19 was measured using the 7 item Japanese version of the Fear of COVID 19 Scale. COVID-19 fear scores in patients with HD were compared with scores of adults in April 2020 (the beginning of the pandemic) using an unpaired t test. The association between multidimensional HL and COVID 19 fear scores was estimated using a multivariable adjusted general linear model. Results. A total of 446 patients were analysed, of whom 431 (97%) and nine (2%) received three and two doses of vaccination, respectively. Their COVID 19 fear scores were significantly lower than those of the general population at the beginning of the pandemic (p < 0.001; mean difference -4.4 [95% confidence interval (CI): -5.1 to -3.7]; standardised effect size [ES] 0.77). Higher functional HL was associated with less fear (per 1-pt higher: -2.8 [95% CI: -1.7 to -0.3]; standardised ES -0.51), whereas higher critical HL was associated with greater fear (per 1-pt higher: 3.2 [95% CI: 0.7 to 3.0]; standardised ES 0.80). Communicative HL was not associated with fear. Conclusion. Patients fear of low functional HL, despite widespread vaccination, can be reduced by providing health information in an easy to understand manner. Thus, the fear of sceptics owing to excessive critical HL and honest explanations by healthcare providers may be important.

The authors have declared no competing interest.

This study was supported by JSPS KAKENHI (grant numbers JP19KT0021 and JP24K14750).

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This study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board of Fukushima Medical University (approval number: ippan2021-292).

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All data produced in the present study are available upon reasonable request to the authors