Shorter blood donation intervals safe and achievable with reminders

By Bianca Nogrady 
Shortening the interval between blood donations is not associa­ted with negative impacts on donors’ quality of life, physical activity or cognitive function, a new UK study suggests. How­ ever, an Australian expert has noted that a more important challenge is getting existing donors to donate at even close to the current permitted frequency of blood donation. 

In a paper published in The Lancet, researchers reported the results of a two­-year trial in 45,263 whole blood donors – 22,466 men and 22,797 women. 

Men were randomly assigned either to the standard 12­-week donation interval, or to a 10­ or eight­-week interval, while women were randomised either to the standard 16-week interval, or to an interval of 14 or 12 weeks.

The protocol included a program of email, text message and telephone reminders about donation. 

Over two years, the mean amount of blood collected per female donor had increased by 0.84 units in the 12­-week group and 0.46 units in the 14­-week group compared with the 16­-week group. In men, the 8-week group donated an average of 1.69 more and the men in the 10­-week group donated 0.79 more units compared with those in the 12-week group. 

The median times between donations in women were 16.6 weeks in those in the 16­-week group, 14.3 weeks in the 14-week group, and 12.7 weeks in the 12­-week group. In men, the median times were 12.3 weeks in the 12­-week group, 10.1 weeks in the 10-week group and 8.3 weeks in the 8­-week group. 

Researchers saw no significant differences between the groups in quality of life, physical activity or cognitive function. However, they did note a moderate increase in self­ reported symptoms, such as feeling faint, tiredness, breathlessness, dizziness and restless legs, in the groups assigned to more frequent donations, particularly among men. 

There were also significantly more deferrals for low haemo­globin, and lower mean haemoglobin and ferritin con­centrations in the more frequent donation groups compared with the standard frequency groups. 

Commenting on the study, Professor David Irving, Director of Research and Development at the Australian Red Cross Blood Service, said although the outcomes in terms of quality of life weren’t such a surprise, the strongest message was the value of regular reminders.

‘We get an average of about 1.5 donations a year per donor, and about half of our donors will return more frequently than that,’ Professor Irving told Medicine Today, pointing out that the minimum interval between whole blood donations in Australia is 12 weeks. 

‘This study does show that certainly it’s safe for them to change their interval, but also the take­-home message is that a reminder system is really most likely to make people return.’ 
Lancet 2017; 

Picture credit: © Kasto/