Saturday, March 03, 2012

Blood donor questions about heterosexual sex (Musings on cultural differences in predonation screening)

Another blog that's a short snapper


Normally I would not read a research paper about blood donors in Brazil, but the following paper in January's AABB's Transfusion caught my eye:
Brazilian blood centers ask candidate blood donors about the number of sexual partners in the past 12 months. Candidates who report a number over the limit are deferred. The authors studied the implications of this practice on blood safety.
    Who can resist a paper involving sex? In a prior life as an instructor, including sex in lectures always increased student interest, e.g, discussing the so-called 'patient zero' in the AIDs tragedy, Air Canada fight attendant Gaëtan Dugas.


    In two Brazil blood centres (São Paulo and Recife), the question about sexual partners during predonation interview is: 
    • “How many sexual partners have you had in the past 12 months?” 
    In another (Belo Horizonte), the question is: 
    • “Have you had more than one sexual partner in the past 12 months? (If yes) How many?” 
    Current criteria to defer donors are more than 6, 3, and 2 heterosexual partners in the past year in São Paulo, Recife, and Belo Horizonte, respectively.


    Can you imagine blood donors in Australia, Canada, NZ, UK, or USA answering such questions about their sex life? I cannot. 


    The Brazilian study is summarized in the ABSTRACT. As would be expected, the number of recent heterosexual partners was associated with HIV positivity and overall rates of serologic markers of sexually transmitted infections. 

    Interestingly, in two centres, first-time, younger, and more educated donors were associated with more recent sexual partners (p < 0.001). 
    • Younger donors having more sex contacts seems reasonable as sexual activity tends to decrease with age, at least before Viagra. <8-) 
    • First-time donors having more sex may be related to them being younger. But researchers suggest it's also related to donors learning on subsequent donations to lie about sexual history once they know that a history of multiple sexual partners will defer them.
    • About more educated donors being associated with more recent sexual partners, that's interesting. Could it be that more educated donors are younger? (Presumably researchers controlled for that variable.) Or perhaps educated donors have increased opportunities for more sexual partners?
    Precautions
    Studies that rely on participants honestly answering questionnaires inherently have limitations. 


    When sex is involved, limitations increase exponentially. Think of surveys where men invariably report a more active sex life than women. 


    Bottom Line
    If you are a blood donor and were asked about recent sex contacts (heterosexual contacts):
    • Would you be offended at the invasion of privacy?
    • Would you answer honestly, especially if you knew that 2 or 3 or 6 or more would defer you?
    Regarding answering predonation questionnaires, are Brazilian donors any different than you?

    For Fun
    Sexy songs by Canadians? 
    As always, views are mine alone. Comments are most welcome BUT, due to excessive spam, please e-mail me personally or use the address in the newsletter notice.