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Challenges in evaluating and changing donor criteria Dr. Mindy Goldman Transfusion Medicine Residents April 30, 2008
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2 Plan Importance of donor criteria Current donor screening and deferrals Factors affecting donor responses Evolution of donor criteria Assessment of questionnaire, criteria
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3 RECIPIENT SAFETY DONOR CRITERIA BLOOD AVAILABILITY DONOR SATISFACTION DONOR SAFETY OPERATIONAL EFFICIENCY PUBLIC PERCEPTION
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4 Donor screening Donor vital signs Donor hemoglobin (Hgb) Donor assessment questionnaire (DAQ) – Questions 1-13 self-administered – Questions 14-29 administered by staff – 87 items queried – Identical for 1 st time, repeat donors
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5 Donor deferrals ~ 15% of donors deferred on clinic
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6 Indefinite deferrals 4% of deferrals are indefinite
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7 Indefinite deferral, HIV or hepatitis risk First time donors, 1990-2005
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8 Prevalence of HCV per 100,000 donations 1990-2005
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9 Factors affecting donor responses Donor characteristics – Language comprehension – Memory – Motivation
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10 Factors affecting donor responses Mode of administration – Self-administration – Face-to-face interview – Computer administered – Privacy Formulation and order of questions
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11 Components of response Comprehension Retrieval Judgement Selecting and reporting answers
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12 Evolution of donor criteria Developed over time as new knowledge, threats emerged Many FDA, Health Canada requirements Little validation that question formulation elicits appropriate information Differences across jurisdictions demonstrates not based on scientific data
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13 Donor selection vs testing 100% 10% 0123 Laboratory Test Utility of donor selection
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14 Methods of assessment of criteria Impossible to do a randomized, controlled trial Difficult to isolate the effect of an individual criteria Difficult to choose appropriate outcome measure Difficult to prove that there will be “zero risk increase” for recipients or donors with a given change in criteria
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15 Methods of assessment, donor questionnaire Surveys of undeclared, reportable risks Operational outcome measures – Post-donation information Cognitive research methods – Degree of correlation, alternative wording – Qualitative methods such as focus groups
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16 Methods of assessment, donor questionnaire Evaluation of donor recall of items queried DAQ in various formulations and modes of administration – Self-administered – Audiovisual computer-assisted format
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17 Assessment of changes, recipient safety Rates of transmission of HIV, hepatitis are too low to measure changes, risk modelling can be done Perform TD testing in deferred donors Assess risk factors, TD positive donors Perform donor surveys to estimate anticipated donor loss/gain Follow TD marker rates after making a change Experience in other countries
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18 Recipient safety criteria Some successful changes – Removal of the question about fever and headache in the week before donation for WNV – Shortening of deferral period from 12 to 6 months for tattoo, piercing, needle-stick injury
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19 Recipient safety criteria Some challenges – Question and deferral for having sex with someone whose sexual background you don’t know – Intranasal cocaine use – Indefinite deferral for men who have sex with men, even once since 1977
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20 History of deferral criteria, MSM Implemented in Canada in the mid-1980s By 1989, listed on the donor health assessment questionnaire Requirement by FDA, Health Canada, Canadian Standards for Blood and Blood Components FDA Blood Products Advisory Committee held workshops in 2000 & 2005 to reassess criteria
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21 History of deferral criteria, MSM Although FDA has not changed their requirement, AABB and US blood suppliers (ABC, ARC) have supported a change to a 12 month deferral period Neither AABB, ABC, or ARC has supported removal or modification of the deferral criteria other than a change to a shorter deferral period
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22 History of deferral criteria, MSM In Canada, 2001 joint CBS/Héma-Québec Consensus Conference on Optimizing the Donor Process – Current process extremely safe – No specific recommendations for changes for the MSM criteria – Advocated continued reassessment of the value of screening questions, based on evolving data
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23 Challenges in maintaining the current criteria Time period “since 1977” is effectively becoming a life-time deferral Advances have been made in the 2 other components of blood safety; testing and Good Manufacturing Practices Direct donor loss of individuals deferred by the criteria Indirect donor loss of individuals not directly affected, but feel criteria is discriminatory
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24 Challenges in maintaining the current criteria Perceived misalignment with deferral periods for other risk categories Potential view of Canadian Blood Services as unnecessarily discriminatory by the public Changes in social policy have occurred with respect to a group that has been discriminated against in the past
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25 Challenges in changing the current criteria Lack of data to support possible approaches Regulated system with very low measurable risks, Mathematical modelling based on many assumptions Extremely difficult to perform studies to obtain data
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26 Challenges in changing the current criteria Any incremental risk is borne by recipients, who have a right to the safest possible transfusion Public history of past tragedies of HIV, HCV transmission
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27 Assessment of changes, donor safety Analysis of adverse events, current criteria Adverse effects in autologous donors Experience in other countries Increase surveillance after changing criteria
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28 Donor safety criteria Some successes – Acceptance of donors on antihypertensive medications – Acceptance of donors with celiac disease – Increase in maximal age of donation for regular donors
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29 Donor safety criteria Some challenges – Hemoglobin deferral criteria for female donors – Donors pulse rate and regularity – Donors on insulin
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30 Conclusions Donor criteria play an important part in ensuring donor and recipient safety, adequacy of supply Approximately 15% of donors are deferred on the clinic, 4% of donors are deferred indefinitely Many factors affect donor responses to screening questions Evaluation of the donor questionnaire, and criteria to protect recipients or donors is challenging
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