Sat 28 Sep 2013
« Back to News
A study presented at the American Society for Clinical Pathology (ASCP) 2013 Annual Meeting this month showed that of the less than 20% of patients with diabetes who meet the nationally recommended frequency for glycated haemoglobin (HbA1c) testing, more than a third are not prescribed treatment changes when their levels increase significantly. The recommendations for frequency of HbA1c testing in the US are the same as in Australia; people with diabetes should have an HbA1c test every 6 months if their plasma glucose levels are within target range, and every 3 months if they are not achieving glycaemic control or if their therapy has changed. The goal for most people with diabetes will be in the 6.5–7% (48–53mmol/mol) range however this may need to be higher for children and the old and frail. Your doctor will advise.
An Australian NHMRC (National Health & Medical Research Council) report in 2003, found using Medicare data, that around 25 per cent of people with diabetes were having their HbA1c measured as often as recommended. A subsequent report reviewed data from 2004 to 2007 and found a large variation in reports from various sources with proportions meeting the recommended frequency ranging from 25 to 80 percent depending on the group of diabetics studied.
The American researchers analysed data from the 737 patients who underwent HbA1c testing at the recommended frequency. They used reference change value — the change in HbA1c level between 2 tests — to assess the statistical significance of differences in serial laboratory results from individual patients, and determined that a change in HbA1c of 0.6% or more in their population was statistically significant. They then decided that they should add this information to their HbA1c reports to inform referring doctors that they might need to consider diabetes management changes in particular patients.
However Dr. Daniel Einhorn medical director of the Scripps Whittier Diabetes Institute in San Diego and President of the American College of Endocrinology commenting on the study, stressed that a statistically significant change in HbA1c does not necessarily mean it is clinically meaningful. Even when it is, a clinician must consider many variables when deciding whether to change a patient's treatment, he said.
"The decision to add a drug or more education time is not without consequence, whether it is cost or potential side effects," he said.