Analysis of blood donor deferral in Japan: characteristics and reasons

Background and objectives: To ensure an adequate and safe blood supply, it is crucial to select suitable donors according to stringent eligibility criteria. This study aims to evaluate donor deferral rates, causes of deferral, and characteristics of deferred Japanese donors.

Materials and methods: Computerized records of blood centers in Miyagi and Fukushima Prefectures from March 2010 through March 2011 were retrospectively analyzed.

Results: Among 231,361 individuals presenting during this period, 186,513 had complete data. Of these 160,763 (86%) attempted donation and 25,750 (14%) were deferred. The overall proportion of deferrals was higher among those less than 20 years old (24% vs 13%, P<0.0001), female (26% vs 7%, P<0.0001), and first-time donors (28% vs 12%, P<0.0001). Factors that were significantly associated with deferral status were female sex [Odds ratio (OR)=4.40], first-time donation attempt (OR=2.42), and donation at Fukushima blood centers (OR=0.57). Main reasons for temporary deferral were low hemoglobin and questionnaire-based interview decisions.

Conclusions: First-time and female were more frequently deferred whereas those presented at Fukushima blood centers were less frequently deferred. Low hemoglobin was the major contributor for female donors. Strategies to minimize deferral are needed to ensure an adequate and safe blood supply.