New Results from a Multi-Center, Prospective Study of

Blood Donor Iron StatusREDS-II Donor Iron Status Evaluation (RISE)

Ritchard G. Cable

for the National Heart, Lung, and Blood InstituteRetrovirus Epidemiology Donor Study-II (REDS-II)

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Objectives of Today’s Presentation

• Briefly review iron depletion in whole blood donors• Review RISE Study design and Objectives• Present current data from and future analysis plans for the RISE study• Assess fingerstick measurement as a proxy for venous hemoglobin• Review data from July 2010 BPAC meeting on proposed changes in donor hemoglobin/frequency• Discuss implications for blood center practice

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REDS-II Blood Centers

American Red Cross Blood Services, New England RegionR. Cable, J. Rios and R. Benjamin

American Red Cross Blood Services, Southern Region/Department of Pathology and Laboratory Medicine, Emory University School of Medicine

J.D. Roback

Hoxworth Blood Center, University of Cincinnati Academic Health CenterR.A. Sacher, S.L. Wilkinson and P.M. Carey

Blood Centers of the Pacific, University of California San Francisco, Blood Systems Research InstituteE.L. Murphy, B. Custer and N. Hirschler

The Institute for Transfusion MedicineD. Triulzi, R. Kakaiya and J. Kiss

Blood Center of WisconsinJ.L. Gottschall and A.E. Mast

Coordinating Center: Westat, IncJ. Schulman and M. King

National Heart, Lung, and Blood Institute, NIHS.A. Glynn, T. Mondoro, and E. Wagner

Central Laboratory: Blood Systems Research InstituteM.P. Busch and P. Norris

Acknowledgements

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• Many studies have shown iron depletion (low ferritin) in blood donors.• Observational, cross sectional studies have shown

– Expected sex differences.– Lower ferritin levels in regular donors, related to donation

intensity.– Finch CA, et al. Blood 1977; 50:441-447 – Simon TL, et al. JAMA 1981; 245:2038-2043

– Deferred donors drop out and are not represented as repeat donors.

• Comprehensive Longitudinal (Cohort) studies are not available.

Previous Studies - Blood Donor Iron Status

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RISE Study Design

Two cohorts of blood donors were recruited and enrolled in the RISE study:

– A first time and reactivated donor cohort, with no whole blood/red cell donations in the previous two years.

– A frequent donor cohort, with ≥2 (F) or ≥ 3 (M) donations in the past year.

Enrolled donors agreed to donate frequently for the 15-24 month study period.

Iron status and related variables were evaluated at baseline and at the end of the study. In addition donation outcomes were recorded for all visits, and additional iron measures were performed on interim visits of:

- First time/Reactivated donors.- Donors with hemoglobin deferrals.- Selected female repeat donors.

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RISE Enrollment

Cohorts StudyTargets

TotalEnrolled

First-time/Reactivated

(no red cell donations past 2

years)

Male 420 407

Female 420 481

Total 840 888

Frequent Male 750 769

Female 750 768

Total 1500 1537

Total 2340 2425

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RISE Baseline Enrollment Data Collection

Hematologic and iron status markers

Iron protein polymorphisms

Donor Questionnaire Data:– Donation History: Lifetime; Past 1,2 years– Smoking: Lifetime, recent– Dietary Iron Consumption– Use of multivitamin/multiminerals and iron supplements– Aspirin use– For women only: Menstrual status/nature of periods;

Detailed pregnancy history

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• Ferritin – Reflects body iron stores – Loss of iron initially leads to a decrease in ferritin (down to ~30 ng/mL).

• Log (sTfR/ferritin) – A specific measure of red cell iron deficit. With further reduction in body iron, ferritin is progressively reduced (down to <12 ng/mL), the red cell elaborates transferrin receptor into the serum (sTfR).

•With further iron loss, red cell hemoglobinization is impaired (change in RBC/reticulocyte indices).

• Iron deficiency anemia - Recognized only when the hemoglobin level drops (usually measured against population norms). Donor deferral occurs at some point, depending on the initial hemoglobin level.

Measures of Donor Iron Used in RISE

9RISE Definitions: Absent Iron Stores (AIS) and Iron Deficient Erythropoiesis (IDE)

Absent iron stores (AIS) is defined as plasma ferritin < 12 ng/mL.

- This is a relatively specific finding, correlating in other studies with absent bone marrow iron stores.

Iron deficient erythropoiesis (IDE) is defined as log(sTfR/ferritin) above the 97.5th percentile for first time/reactivated male donors (negligible risk of IDE).

- This has been shown to best correlate with other measures of IDE.

- For the RISE data set this correlates with log(sTfR/ferritin) ≥ 2.07.

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10Donors with Absent Iron Stores (AIS) and/or Iron Deficient Erythropoiesis (IDE) at Enrollment

Gender Donor Status

AIS% ferritin <12 µg/L

IDE % Log (sTfR/F)

≥ 2.07

Females FT/RA 6.5 24.6

Fqnt 27.0 66.1

Males FT/RA 0 2.5

Fqnt 16.4 48.7

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11Effect of Previous 12 month RBC Donation Frequency on Plasma Ferritin at Enrollment

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12Adjusted Odds Ratios for AIS and IDE at Enrollment by 2 Year Red Cell Donation Frequency

Number of RBC units in 24 months prior to enrollment

AISFerritin<12

Adjusted ORs (95% CI)

IDELog (R/F) ≥ 2.07

Adjusted ORs (95% CI)

p value <0.001 <0.001

FT: 0 donations 1.0 1.0

RA: 0 Donations 0.5 (0.2-1.2) 1.5 (0.9-2.4)

R: ≤ 4 donations 5.3 (2.8-10.1) 14.0 (8.6-22.7)

R: 5-6 donations 12.5 (6.4-24.6) 24.0 (14.3-40.5)

R: 7-9 donations 13.5 (6.8-26.6) 32.3 (19.2-54.5)

R: 10+ donations 18.9 (9.0-39.6) 50.5 (28.4-89.9)

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*Adjusted for Gender, Age, Blood Center, Weight, Smoking, Fe+ supplementation, HFE, Menstrual status, Pregnancy

13Adjusted Odds Ratios for AIS and IDE at Enrollment by Age

Age(in yrs)

AISFerritin<12

Adjusted* ORs (95% CI)

IDELog (R/F) ≥ 2.07

Adjusted* ORs (95% CI)

Male Female Male Female

p value 0.31 <0.0001 0.01 <0.0001

<20 0.4 (0.0-3.3) 3.1 (1.0-9.6) 1.1 (0.7-5.9) 4.9 (1.9-12.5)

20-29 1.8 (0.8-4.2) 3.9 (2.0-7.6) 2.3 (1.2-4.3) 3.1 (1.8-5.4)

30-39 1.5 (0.7-3.2) 1.6 (0.9-3.0) 1.7 (1.0-2.9) 1.7 (1.0-2.8)

40-49 1.0 1.0 1.0 1.0

50-59 1.6 (0.9-2.9) 1.0 (0.6-1.7) 1.4 (0.9-2.2) 0.8 (0.5-1.2)

60+ 0.9 (0.5-1.9) 0.7 (0.3-1.3) 1.2(0.8-2.0) 0.8 (0.5-1.4)

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*Adjusted for Previous RBC donations, Gender, Blood Center, Weight, Smoking, Fe+ supplementation, HFE, Menstrual status, Pregnancy

14Other Significant Enrollment Variables (other than gender) in the Adjusted Models for AIS and IDE

• Weight: Reduced odds of AIS and IDE in the heaviest donors.

• Smoking: Past and current smokers have lower odds for IDE than do donors who never smoked.

• Self-prescribed iron supplement: Donors taking iron supplements (with or without multivitamins) are slightly less likely to have AIS, OR = 0.7.

• HFE genotype: Donors homozygous or mixed heterozygous for C282Y and/or H63D are less likely to have IDE.

• Pre-menopausal or ever pregnant status: Women with either status are more likely to have IDE.

• Center

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15RISE Longitudinal Study – Frequency of Return by Cohort

FT/RAFemales

FT/RAMales

FrequentFemales

Frequent Males

Enrolled at Baseline

481 407 769 768

Donors w/ no follow-up visits

102 (21.2%)

119 (29.2%)

30 (3.9%)

19 (2.5%)

Donors w/ one or more follow-up visits

379 (78.8%)

288 (70.8%)

739 (96.1%)

749 (97.5%)

Average return visits*

2.6 2.9 4.4 5.2

Average time in study*

429 days 440 days 516 days 524 days

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* For donors with one or more return visits

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12,695 total RISE donor visits• 2,425 Enrollment Visits (no deferrals)

10,270 follow-up visits• 8956 Donations• 945 Hemoglobin Deferrals (84% Female, 16%

Male)• 268 Other Deferrals • 101 Sample Only Visits

RISE Longitudinal Study –Visits/Data Points of RISE donors

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Statistical Methods - Modeling

• Repeated measures logistic regression models were developed to predict AIS and IDE at all visits

• Similar models were developed to predict hemoglobin deferral at any return visit.

– Enrollment visits not included in model since only accepted donors were enrolled

• These models account for multiple measurements on the same donor.

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18Variables Included in the Model Predicting Hemoglobin Deferral at any Return Visit

Variables significant in the adjusted model:• Female Gender• Black Race• Younger Age in Women, not Men• Blood Center• Time since last RBC donation

Variables not significant:• Iron supplements• Weight• Smoking• Menstrual status• HFE status• Previous donation a WB or double red cell •Number of RBC units in previous 24 months

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Adjusted Odds Ratio 95% CI

Black vs. White 2.1 1.3-3.5

Hispanic vs. White 1.6 1.0-2.7

Asian vs. White 1.2 0.7-2.3

Other vs. White 1.7 0.9-3.5

Female vs. Male 6.3 3.8-10.5

Age Male Female

<30 vs. 40-49 0.9 0.2-3.2 1.7 1.2-2.4

30-39 vs. 40-49 0.9 0.3-2.9 1.1 0.8-1.5

50-59 vs. 40-49 1.9 0.9-4.0 0.9 0.7-1.3

60+ vs. 40-49 1.6 0.8-3.5 0.7 0.5-1.1

Demographic Variables Predicting Hemoglobin Deferral

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Effect of Donation Interval on Hemoglobin Deferral: Adjusted ORs (vs. ≥ 26 weeks)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

8 9 10 11 12 13 14 15 16 17 18 19 20-25

Weeks since last RBC donation

Odd

s Ra

tio

(95%

CI)

• Mean ORs for all donations are represented by Gray squares and CI bars.• Blue diamonds represent mean ORs for female donations only.• Insufficient male deferrals to analyze by week

21Variables Included in the Models Predicting AIS and IDE at any Visit

Significant Variables:

• Female Gender and Younger Age in Women• Time since last RBC donation• Number of RBC units in previous 24 months• Smoking• Taking Iron• Blood Center

Variables minimally or not significant:

• Race• Weight• Menstrual status• Previous donation a WB or double red cell • HFE status

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Significant Variables Predicting AIS22

Adjusted Odds Ratio 95% CI

RBCs donated in last 2 yrs

<4 donations vs none 2.5 1.6 - 3.9

4-6 donations vs none 9.2 5.6-15.0

7-9 donations vs none 6.4 4.0-10.1

10+ donations vs none 8.6 5.3-14.0

Iron Supplements

Takes supplemental iron vs. None

0.6 0.5-0.7

Smoking

Current vs. Never 0.6 0.4-0.9

Past vs. Never 0.8 0.6-1.0

Gender

Female vs. Male 2.9 1.9-4.7

Effect of Donation Interval on Iron Stores (AIS): Adjusted ORs (vs ≥ 26 weeks)

• Mean ORs for all donations are represented by Gray squares and CI bars.• Blue diamonds represent mean ORs for female donations only.• Insufficient male AIS to analyze by week

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8 9 10 11 12 13 14 15 16 17 18 19 20-25

Weeks since last RBC donation

Odd

s Ra

tio

(95%

CI)

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Summary of Hemoglobin Deferral and AIS Models

• The most significant predictors of hemoglobin deferral were: – Fewer weeks since last RBC donation

▪ But not number of RBC donations in the last two years – Black race– Female Gender– Younger age in women– Blood Center

• Significant predictors of severe iron depletion (AIS) were similar, except for race. Other predictors of AIS were:

– RBC Donations in the last two years– Smoking and iron supplements had a protective effect

• Hemoglobin deferral was more likely if a donor attempted to donate within 14 weeks of his/her last donation and AIS more likely within 19-20 weeks.

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Assessment of Fingerstick Hemoglobin

• Nearly all blood donor qualification schemes depend on capillary sampling of the donor’s finger.

•Earstick sampling produces values that are higher than venous values. Fingerstick sampling more closely approximates venous hemoglobin.

– Woods et al. Transfusion 2001

•The RISE study determined fingerstick Hgb/Hct in routine blood center practice along with simultaneous venous hemoglobin, allowing comprehensive assessment of the accuracy of fingersticks.

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Donor Qualification Methods at REDS-II Centers

Blood Center

Hemoglobin or Hematocrit Device

A Hematocrit Hematastat

B Hematocrit Hematastat

C Hematocrit Hematastat

D Hematocrit UltraCrit

E Hemoglobin HemoCue B

F HemoglobinHemoCue Donor

Checker

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27Fingerstick/Venous Hemoglobin Values in 2425 RISE Donors, by Gender and Iron Status

Females with AIS (n=239)

FSFS

FS

FS

V

V V

V

Females with No AIS (n=1011)

Males with AIS (n=126)

Males with No AIS (n=1049)

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11

12

13

14

15

16

17

18

19

20

Hem

og

lob

in g

/dL

FS and Venous Groups

28Frequency of Donors Passing FS Qualification Method but with Venous Hgb < 12.5 g/dL

Iron Status Female Male

AISFerritin < 12 ng/mL

46.4%(n=239)

25.4%(n=126)

No AISFerritin ≥ 12 ng/mL

18.4%(n=1011)

1.8%(n=1049)

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Conclusion - Fingerstick/Venous Analysis

• FS Hgb or Hct is a reasonable estimate of venous Hgb for male donors without iron depletion.

• However in females and all donors with absent iron stores, FS overestimates venous Hgb values.

• This is a significant limitation of fingerstick testing which should be considered in setting hemoglobin requirements.

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Four Questions posed by FDA

What would be the impact of changing the minimum predonation Hemoglobin from 12.5 g/dL…

1. …to 13.0 g/dL for men? …to 13.5 g/dL for men?

2. …to 12.0 g/dL for women?

What would be the impact of changing the interdonation interval from 8 weeks (about 6-7 times per year) …..

3. ….to 12 weeks (about 4-5 times per year) for men?4. ….to 16 weeks (about 3-4 times per year) for

women?

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ARC Balance Sheet

Minimum Hemoglobin

Current Proposed Difference in Donations

Percent Gain or

Loss

Men12.5

13.0 - 146,790 - 4%

13.5 - 386,781 - 10%

Women 12.0 +198,200 + 5%

Donation Interval (Frequency)

Men

~ 6 -7

~4-5 (4.33) - 157,378 - 5%

Women ~ 3-4(3.25)

- 261,494 - 7%

This and previous slide courtesy of Anne Eder, American Red Cross

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Some Other Options to Manage Donor Iron

• Monitor donor Iron stores (ferritin?) and alter donation requirements for donors with significant iron depletion

– All donors– Donors at high risk of iron depletion– Implement monitoring programs as a condition of

frequent donation?

• Increase donor iron intake with iron supplements– Blood Center provided versus donor acquired pills– All donors or donors at greater risk– Implement Iron programs as a condition of frequent

donation?

33Planned or In-progress RISE Analyses Related to Laboratory Measures

Identify optimal laboratory measures that predict the development of iron depletion and hemoglobin deferral.

– Examine within donor and between donor correlation among selected laboratory measures of iron stores.

– Develop models to assess the utility of ferritin, sTfR, as well as newer iron measures (hepcidin, and selected red cell/reticulocyte indices) to predict iron depletion and hemoglobin deferral at subsequent visits.

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34Further Actions - Evaluating the Impact of Various Donation Guidelines

• Utilize information from RISE and other REDS-II analyses to project the impact of various blood donation guidelines on the iron status of blood donors, potential for hemoglobin deferral, and the adequacy of the blood supply.

• Engage policy makers in understanding and utilizing REDS-II, RISE and other available data to develop future donor management strategies and eligibility guidelines.

• AABB Committee

• FDA workshop in Fall 2011

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