07258-SickleCell-Booklet.indd i 07258-SickleCell-Booklet.indd i 

or Southeast Asian 

Heritage 

Important 

Informatio

about Diab

Blood Test

U.S. Department 

of Health and 

Human Services 

NATIO

OF H
07258-SickleCell-Booklet.indd ii 07258-SickleCell-Booklet.indd ii 
07258-SickleCell-Booklet.indd iii 07258-SickleCell-Booklet.indd iii 

NATIONAL DIABETES INFORMATION CLEA

For People of African, 

Mediterranean, or 

Southeast Asian Herita

Important 

Information 

about Diabe

Blood Tests 

U.S. Department 

of Health and NATIO

Human Services OF HE
07258-SickleCell-Booklet.indd iv 07258-SickleCell-Booklet.indd iv 

What are some common hemoglobin varia

What is the A1C test? ................................

How do hemoglobin variants affect the A

and my diabetes care?................................

How will I know whether I have a hemog

variant?........................................................

Where can my doctor find more informati

hemoglobin variants and the A1C test? ...

How can I know if my diabetes is well-con

if I have a hemoglobin variant?.................

Points to Remember 

For More Information about Sickle Cell 

..................................

Pronunciation Guide..................................

For More Information about Diabetes ....

and Other Blood Conditions.....................
07258-SickleCell-Booklet.indd 1 07258-SickleCell-Booklet.indd 1 

 

hemoglobin* in your red blood cells that a

your diabetes care. Hemoglobin in red bl

gives blood its red color and carries oxyge

your lungs to all parts of your body. Some 

hemoglobin can cause false results for a d

blood test called the A1C test. If the A1C 

a false result, your doctor may think your 

glucose level is higher or lower than it rea

If you are of African, Mediterranean, or Southe

heritage, you could have a variant form of hemo

your red blood cells that affects your diabetes c

*See page 7 for tips on how to say the wo

bold type. 
07258-SickleCell-Booklet.indd 2 07258-SickleCell-Booklet.indd 2 

Most people have only one kind of hemog

called hemoglobin A. Some people have b

hemoglobin A and another kind such as h

S, C, or E. These less common forms of h

are called hemoglobin variants. You can 

hemoglobin variant but not know it becau

might not have any symptoms of blood dis

Having a variant without symptoms of the 

is also called having the trait or being a ca

Many people have heard of sickle cell tra

occurs most often in people of African he

Again, having the trait means you inherit

for a hemoglobin variant from one paren

carry information about which characteri

passed down from parents to children. P

with sickle cell trait usually have no symp

(Inheriting genes from both parents for th

hemoglobin “S,” however, results in sickl

disease, which is painful. You would kno

had sickle cell disease.) 

People of Mediterranean or Southeast A

heritage also can inherit hemoglobin vari

Some of these variants cause no symptom

cause some health problems. Variant hem

does not increase your risk for diabetes. 

2 
07258-SickleCell-Booklet.indd 3 07258-SickleCell-Booklet.indd 3 

The A1C blood test, also called the hemo

A1C test or glycohemoglobin, provides in

about your average blood glucose levels f

past 2 to 3 months. People with diabetes 

have the A1C test at least twice a year. Y

doctor uses the results of your A1C tests 

see whether you need changes in your dia

medicine, meal plan, or physical activity r

keep your diabetes under control. 

How do hemoglobin variants a

the A1C test and my diabetes c

A variant form of hemoglobin in your blo

give you false A1C test results. If your te

is falsely high, your doctor might change y

diabetes medicine or make other changes 

you take care of your diabetes. These cha

could cause low blood glucose, or hypogly

If your test result is falsely low, your doct

make changes in your treatment that cou

your blood glucose to stay too high, incre

risk for diabetes problems in your eyes, n

kidneys. Not all A1C tests are affected by 

hemoglobin. Your doctor can take steps 

sure you get accurate results from your A
07258-SickleCell-Booklet.indd 4 07258-SickleCell-Booklet.indd 4 

g

Many people with hemoglobin variants h

symptoms. You might be at risk for havin

hemoglobin variant if
 

• you are of African, Mediterranean, or S

Asian heritage 

• members of your family have sickle cel

sickle cell anemia 

• the results of your self blood glucose m

don’t match the results of your A1C tes

• your A1C result is different than expec

• your A1C result is high—more than 15 

• your most recent A1C result is very diff

from your last A1C result 

Laboratory tests can confirm whether you 

hemoglobin variant. 

4 
07258-SickleCell-Booklet.indd 5 07258-SickleCell-Booklet.indd 5 

g

variants and the A1C test? 

The fact sheet Sickle Cell Trait and Other 

Hemoglobinopathies and Diabetes: Impor

Information for Physicians provides inform

online at www.diabetes.niddk.nih.gov/dm/p

hemovari-A1C. Or your doctor can reque

copy by calling the National Diabetes Inf

Clearinghouse at 1–800–860–8747. 

How can I know if my diabetes 

well-controlled if I have a hemo

variant? 

Some A1C tests give accurate results in p

a hemoglobin variant. Your doctor can a

for your A1C test to be done at a laborato

gives accurate results for people with a he

variant. Your daily blood glucose tests ca

show how well-controlled your diabetes is

blood glucose test gives information at on

point in time. 
07258-SickleCell-Booklet.indd 6 07258-SickleCell-Booklet.indd 6 

 If you are of African, Mediterranean, o

Southeast Asian heritage, you are at ris

having a hemoglobin variant. 

• You can have a variant form of hemogl

not know it. 

• Hemoglobin variants don’t cause diabe

they can affect diabetes test results. 

• If you have a variant form of hemoglob

results of your A1C test might not be a

The results might show that your avera

glucose level is higher or lower than the 

level. 

• Your doctor needs accurate results from 

A1C test in order to plan how best to c

your diabetes. 

• Your doctor can read more about hem

variants and the A1C test in Sickle Cell 

and Other Hemoglobinopathies and Dia

Important Information for Physicians, a 

sheet available from the National Diab

Information Clearinghouse. 

6 
07258-SickleCell-Booklet.indd 7 07258-SickleCell-Booklet.indd 7 

glycohemoglobin (GLYkohHEEmohG

hemoglobin (HEE-moh-GLOH-bin)
 

hemoglobin variants (HEE-moh-GLOH-

(VAIR-ee-uhnts)
 

hypoglycemia (HY-poh-gly-SEE-mee-uh

sickle cell trait (SIH-kul) (sel) (trayt)
 
07258-SickleCell-Booklet.indd 8 07258-SickleCell-Booklet.indd 8 

National Diabetes Information Clearingh

1 Information Way 


Bethesda, MD 20892–3560 


Phone: 1–800–860–8747 


Fax: 703–738–4929
 

Email: ndic@info.niddk.nih.gov
 

Internet: www.diabetes.niddk.nih.gov 


National Diabetes Education Program 

1 Diabetes Way 

Bethesda, MD 20892–3560 

Phone: 1–800–438–5383 

Fax: 703–738–4929 

Email: ndep@mail.nih.gov 

Internet: www.ndep.nih.gov 

American Diabetes Association 

1701 North Beauregard Street 

Alexandria, VA 22311 

Phone: 1–800–DIABETES (342–2383) 

Fax: 703–549–6995 

Email: AskADA@diabetes.org 

Internet: www.diabetes.org 

8 
07258-SickleCell-Booklet.indd 9 07258-SickleCell-Booklet.indd 9 

National Heart, Lung, and Blood Institut

Health Information Center
 

P.O. Box 30105
 

Bethesda, MD 20824–0105
 

Phone: 301–592–8573
 

Fax: 240–629–3246
 

Email: nhlbiinfo@nhlbi.nih.gov
 

Internet: www.nhlbi.nih.gov
 
07258-SickleCell-Booklet.indd 10 07258-SickleCell-Booklet.indd 10 
07258-SickleCell-Booklet.indd 11 07258-SickleCell-Booklet.indd 11 

g

1 Information Way 

Bethesda, MD 20892–3560 

Phone: 1–800–860–8747 

Fax: 703–738–4929 

Email: ndic@info.niddk.nih.gov 

Internet: www.diabetes.niddk.nih.gov 

The National Diabetes Information Clearinghouse (NDIC) 

of the National Institute of Diabetes and Digestive and Kid

(NIDDK). The NIDDK is part of the National Institutes o

U.S. Department of Health and Human Services. Establish

the Clearinghouse provides information about diabetes to p

diabetes and to their families, health care professionals, and 

The NDIC answers inquiries, develops and distributes publ

and works closely with professional and patient organizatio

Government agencies to coordinate resources about diabet

Publications produced by the Clearinghouse are carefully r

by both NIDDK scientists and outside experts. This public

reviewed by Randie R. Little, Ph.D., National Glycohemog

Standardization Program, University of Missouri School of 

This publication is not copyrighted. The Clearinghouse 

users of this publication to duplicate and distribute as m

as desired. 

This booklet is also available at www.diabetes.niddk.nih.g

This publication may contain information about medication

to treat a health condition. When this publication was prep

NIDDK included the most current information available. O

new information about medication is released. For updates 

questions about any medications, please contact the U.S. F

Administration at 1–888–INFO–FDA (463–6332), a toll-fre

their website at www.fda.gov. Consult your doctor for more 
07258-SickleCell-Booklet.indd 12 07258-SickleCell-Booklet.indd 12 

U.S. DEPARTMENT OF HEALTH 

AND HUMAN SERVICES 

National Institutes of Health 

 

National Institute of Diabetes and 

Digestive and Kidney Diseases 

NIH Publication No. 08–6283 

November 2007