Red blood cell variance from liver disease alters HbA1c readings
When treating adults with diabetes and liver disease who are being evaluated for transplant, HbA1c should not be used to determine blood glucose level, according to findings published in Diabetic Medicine.
“Whilst the WHO bulletin lists medical conditions and drugs that may affect HbA1c, it provides no references to quantitative evidence,” Susan Manley, PhD, of the Institute of Translational Medicine at University Hospitals Birmingham NHS Foundation Trust in Birmingham, U.K., and colleagues wrote. “Evidence is accumulating that various coexisting conditions affect HbA1c and result in misdiagnosis or mismanagement of diabetes.”
Manley and colleagues compared HbA1c levels and red blood cell morphology in 125 adults with diabetes and no liver disease who were recruited from Queen Elizabeth Hospital in Birmingham in the U.K. from 2007 to 2009 (mean age, 60 years; 31% women) and 29 adults with diabetes and liver disease who were being considered for liver transplantation at Queen Elizabeth Hospital from 2008 to 2012 (mean age, 55 years; 28% women). Liver diseases that were present included nonalcoholic fatty liver disease, hepatitis C, alcoholic liver disease, hereditary hemochromatosis, polycystic liver and kidneys and cryptogenic/noncirrhotic portal hypertension.
The researchers found that those with diabetes and liver disease had lower HbA1c levels (41 mmol/mol; 95% CI, 32-56) compared with those with diabetes and no liver disease (61 mmol/mol; 95% CI, 52-70). Adults with liver disease had lower red blood cell counts (P < .001), decreased hemoglobin (P < .001) and hematocrit (P < .001), and greater red blood cell distribution width (P < .001), red blood cell volume (P = .001) and red blood cell hemoglobin (P = .028) compared with those without liver disease.
“This probably reflects a shorter red blood cell half-life and less exposure of hemoglobin to glucose. ... This effect on HbA1c in people with cirrhotic liver disease will cause misdiagnosis of diabetes and inappropriate clinical care,” the researchers wrote. “Monitoring glycemia during the post-liver-transplant period is also an issue, as it is well-known that posttransplant anemia renders HbA1c unsuitable for clinical interpretation for [approximately] 6 months.” – by Phil Neuffer
Disclosures: The authors report no relevant financial disclosures.