AVAILABILITY OF BIOLOGIC SAMPLES FROM DIABETIC STUDY POPULATION

Release Date:  July 13, 1999

National Institute of Diabetes and Digestive and Kidney Diseases

PURPOSE
The National Institute of Diabetes and Digestive and Kidney 
Diseases (NIDDK) announces that a portion (1/3) of all 
stored non-renewable samples (plasma, serum, urine) from 
subjects enrolled in the Diabetes Control and Complications 
Trial (DCCT) is available for use by the scientific 
community to address questions for which these samples are 
uniquely invaluable.  The DCCT was a randomized, controlled 
clinical trial conducted at 29 centers in the U.S. and 
Canada.  A total of 1,441 patients between the ages of 13 
and 39 years with insulin-dependent diabetes for 1-15 years 
were recruited during 1983 through 1989.   Approximately 
half of these subjects had no retinopathy and half had mild 
retinopathy.  Patients were randomly assigned to 
conventional or intensive diabetes treatment and followed 
for a mean of 6.5 years for the appearance and progression 
of retinopathy and other complications.  The DCCT 
demonstrated that intensive treatment reduced the risks of 
development or progression of retinopathy, nephropathy, and 
neuropathy by 35-75 percent, depending on the outcome 
measured.  

During the course of the study, blood (plasma and serum) 
and urine samples were obtained at baseline and annually 
for up to 10 years.  The final DCCT sample was obtained at 
the time of study closeout.  These samples were stored 
frozen at –70 degrees centigrade in aliquots at the central 
laboratory at the University of Minnesota.  For each 
available subject at baseline and yearly intervals 
thereafter, the NIDDK is prepared to release up to 4.5 ml 
urine, 1 ml serum, and 1 ml plasma per requestor.  The 
NIDDK will support the costs of aliquotting and 
distributing these samples from the central laboratory for 
highly meritorious approved projects.  This does not 
include DNA or lymphocyte samples.  Associated demographic 
and clinical data on patients, including retinopathy, 
nephropathy, and neuropathy status, can be made available 
from the Biostatistics Center at George Washington 
University. 

APPLICATIONS
To request samples from the DCCT, investigators must 
describe the rationale for the study, the analysis 
proposed, and specific requirements for the samples and 
associated data.  Proposals should be 6-10 pages exclusive 
of tables, figures, and references.  

The investigator must justify the requirement for these 
unique and non-renewable samples.  That is, the request 
must state why the research is dependent specifically on 
the samples from the DCCT and why other sources are 
insufficient for addressing the research objective.  
Proposals to use the DCCT specimens as samples of 
convenience from patients with type 1 diabetes will not be 
considered, such as studies necessary for laboratory assay 
development or validation.  In addition, the investigator 
should address how the proposed study specifically relates 
to the scientific objectives and/or conclusions of the 
DCCT.  The NIDDK’s primary interest is in studies that will 
shed light on the mechanisms underlying the observed DCCT 
treatment effects or novel pathways related to the 
development of diabetic complications, the occurrence of 
hypoglycemia, and weight gain, among other DCCT findings.  
Data on stability of substances to be assayed in the 
proposed studies should be provided, as well as preliminary 
animal and human data that support the hypotheses.  The 
requestor should also address what other data from the DCCT 
database are required in order to test their proposed 
hypothesis.  Specific justification is needed for 
requesting samples that were drawn at DCCT baseline and at 
DCCT closeout since these samples are particularly precious 
and irreplaceable.  For example, the investigator should 
consider whether the proposed study can be accomplished 
just as well with the annual samples obtained one year 
after baseline or prior to DCCT closeout.  

Applicants must also indicate what research funding is 
available or will be sought to conduct the investigation.  
Samples will be provided at no cost.  If required, 
investigators will be expected to pay costs associated with 
data analysis for the retrieval of relevant individual 
subject data, but not the costs of sample retrieval.  The 
deadline for requests is December 31, 1999.

EVALUATION
Requests to utilize samples will be evaluated by a 
committee organized by the NIDDK to include members of the 
Diabetes Control and Complications Trial/Epidemiology of 
Diabetes Interventions and Complications (DCCT/EDIC) study 
group, the DCCT/EDIC Data Coordinating Center, DCCT/EDIC 
Central Biochemistry Laboratory, NIDDK staff, and external 
reviewers.  The DCCT/EDIC study group is presently 
following over 90% of the subjects from the DCCT cohort for 
macrovascular and microvascular endpoints.  Requests will 
be rated based on the importance of the scientific question 
being posed and how it relates to DCCT and EDIC scientific 
objectives, the unique requirement for these particular 
samples, the quality and thoroughness of the proposal in 
outlining the specific hypotheses and methods, and the 
amount of sample required.  Consideration will also be 
given to the willingness of the investigator to share the 
samples with other investigators, thereby maximizing the 
number of investigators using the samples.

ACTION
Investigators will be advised of committee recommendations 
in a letter approving or disapproving the release of 
samples for the proposed investigation.  Release of samples 
will be contingent on documentation that resources are 
available for the proposed project.  If funding for the 
research project is being sought, samples will be released 
to the investigator only after funding has been obtained.  
Approval will be effective for a one-year period. 
Documentation that sufficient funds are available to carry 
out the work proposed using these samples, and that funds 
are available to cover any costs associated with patient 
data retrieval, must be provided within one year after 
approval is received.  Later requests for additional 
samples will be reviewed and evaluated on their own merits.

Please direct requests to:
Catherine C. Cowie, PhD
Director, Type 1 Diabetes Clinical Trials Program
National Institute of Diabetes and Digestive and Kidney 
Diseases
45 Center Drive, Room 5AN24A
Bethesda, MD  20892-6600
Telephone:  (301) 594-8804
FAX:  (301) 480-3503
Email:  cc68v@nih.gov

References:
The Diabetes Control and Complications Trial Research 
Group.  The effect of intensive treatment of diabetes on 
the development and progression of long-term complications 
in insulin-dependent diabetes mellitus.  NEJM 1993;329:977-
986.

The Diabetes Control and Complications Trial Research 
Group.  The Diabetes Control and Complications Trial 
(DCCT):  design and methodologic considerations for the 
feasibility phase.  Diabetes 1986;35:530-45.

The Diabetes Control and Complications Trial Research 
Group.  Diabetes Control and Complications Trial (DCCT): 
results of feasibility study.  Diabetes Care 1987;10:1-19.

The Diabetes Control and Complications Trial Research 
Group.  Diabetes Control and Complications Trial (DCCT):  
update.  Diabetes Care 1990;13:427-33.

The Diabetes Control and Complications Trial Research 
Group.  Feasibility of centralized measurements of glycated 
hemoglobin in the DCCT:  a multicenter study. Clin Chem 
1987;33:2267-71.

The Diabetes Control and Complications Trial Research 
Group.  DCCT data tape archives.  Springfield, VA:  
Department of Commerce, National Technical Information 
Service, 1996.  (Publication no. 96-501895)

The Diabetes Control and Complications Trial Research 
Group.  DCCT protocol.  Springfield, Va.:  Department of 
Commerce, National Technical Information Service, 1988.  
(Publication no.  88-116462-AS).

The Diabetes Control and Complications Trial Research 
Group.  DCCT manual of operations.  Springfield, Va.:  
Department of Commerce, National Technical Information 
Service, 1993.  (Publication no. 93-183382.)

Epidemiology of Diabetes Interventions and Complications 
(EDIC) Research Group.  Epidemiology of Diabetes 
Interventions and Complications (EDIC):  Design, 
implementation, and preliminary results of a long-term 
follow-up of the Diabetes Control and Complications Trial 
cohort.  Diabetes Care 1999;22:99-111.


Return to Volume Index

Return to NIH Guide Main Index


Office of Extramural Research (OER) - Home Page Office of Extramural
Research (OER)
  National Institutes of Health (NIH) - Home Page National Institutes of Health (NIH)
9000 Rockville Pike
Bethesda, Maryland 20892
  Department of Health and Human Services (HHS) - Home Page Department of Health
and Human Services (HHS)
  USA.gov - Government Made Easy


Note: For help accessing PDF, RTF, MS Word, Excel, PowerPoint, Audio or Video files, see Help Downloading Files.