Exhaled Carbon Monoxide and Red Blood Cell Turnover

Status unconfirmed

Conditions studied: Diabetes Mellitus, Healthy

In brief

Hemoglobin A1C (HbA1c) is the cornerstone of blood sugar monitoring. As HbA1c is formed by the covalent reaction of glucose with hemoglobin throughout the lifespan of the red blood cell (RBC), it is used as a surrogate marker for integrated mean blood glucose over time. The HbA1c value therefore is dependent on the average amount of time the RBC spends in the circulation (mean RBC age or MRBC). However, our previous studies measuring red cell lifespan using either an age cohort label (ex vivo labeling with biotin) or a population label (stable isotope) have demonstrated, contrary to established dogma, that the MRBC varies substantially among individuals and is sufficiently variable to affect HA1c interpretation in a significant percentage of individuals with diabetes. Although the stable isotope method is suitable for clinical studies, it has limited potential for application to large population of subjects. A potential alternative to the stable isotope approach that could be applied routinely to the average patient in the clinic is measurement of exhaled carbon monoxide (eCO) concentration, a reflection of RBC heme turnover. In general, the primary advantage of applying exhaled breath analyses to human clinical diagnostics and therapeutic monitoring is that this technique is noninvasive, safe, simple, and provides near-real time measurements. The purpose of this observational study is to optimize the collection of eCO in a normal control population followed by measurement in a cohort of subjects previously assessed by either the SI or biotin methods for comparison.

Key facts

Study ID

NCT03288233

Run by

University of Cincinnati

People needed

30

Starts

2015-04-01

Expected to finish

2018-08-01

Last updated by the study team

2017-09-20

Who can join

Age: 18 and older, up to 75. Sex: any. Healthy volunteers: accepted.

You may qualify if…

• Subjects will be between age 18 and 75 years, non-pregnant, with a goal of equal gender and race (Caucasian vs. African-American) distribution

You may not qualify if…

• known hemoglobinopathy or RBC disorder
• positive pregnancy test (in women of child-bearing potential or are breast feeding or planning pregnancy during the course of the study;
• baseline serum creatinine >1.5 mg/dl
• CBC outside the normal range
• history of GI blood loss or coagulopathy
• urine microalbumin >100 mcg/mg creatinine (spot collection);
• transaminases >3 X the upper limit of normal
• presence of serum antibodies to biotinylated proteins (which could interfere with the biotin RBC labeling protocol)
• greater than or equal to NYHA stage 3 heart failure;
• active infection;
• known rheumatologic disease
• uncontrolled hypo-or hyperthyroidism or an underlying illness known to be associated with either body wasting or changes in serum proteins
• lung transplantation, irradiation, recent surgery, recent intensive care admission, asthma, COPD, cystic fibrosis, smoking, recent hematoma, uncontrolled hypo- or hyperthyroidism or an underlying illness known to be associated with either body wasting or changes in serum proteins (e.g. certain malignancies including multiple myeloma or tuberculosis).

Where it is running

• University of Cincinnati — Cincinnati, Ohio, United States (enrolling)

Full record on ClinicalTrials.gov

Trial information comes from ClinicalTrials.gov and is refreshed daily. TrialsForMe does not provide medical care and does not run the studies it lists.