Prevalence of haemoglobinopathies in the diabetic population served by Connolly Hospital

Introduction: Small shifts in glycaemic control are associated with significant effects on clinical complications in patients with diabetes. Measurement of glycosylated haemoglobin, called HbA1c, is well established as the gold standard for measurement of long-term glycaemic control. However, variations in haemoglobin may alter the validity of HbA1c.

Aim: To determine the percentage of HbA1c tests performed on patients with haemoglobinopathies at Connolly Hospital, with consideration of the possible need for fructosamine measurement in those patients.

Methods: A retrospective chart review covering all patients tested for HbA1c at Connolly Hospital between January 1, 2014, and July 1, 2014.

Results: Some 28 patients out of a total of 3,920 (0.71%) were automatically flagged in laboratory records as demonstrating abnormal haemoglobins upon HbA1c measurement, with 36 HbA1c tests in total (including repeats on individuals) run on these patients over the study period. Nine (four female, five male) had previous records of specific haemoglobin screening tests, all of which were consistent with sickle cell trait.

Conclusion: The number of patients having HbA1c tested at Connolly Hospital who have haemoglobinopathies warrants interpreting their HbA1c results with caution. It is worth considering the need to perform fructosamine measurements regularly in house as an alternative.