The benefits of point-of-care diabetes testing
Posted on 5 November 2019
Point-of-care diabetes testing (HbA1c) is becoming a popular method for office-based monitoring of glucose control.
Diabetes is a serious disease that needs to be managed strictly and carefully. Part of any person with diabetes’ management strategy involves regular testing of blood sugar levels to ensure they are within the normal range – these tests help diabetics avoid life-threatening complications that arise from blood glucose levels that are too low or too high.
For people with either type 1 or type 2 diabetes, blood glucose tests are a quick and simple way to gauge whether their specific management plan is working, explains Dr Elmo Pretorius, a specialist physician and endocrinologist at Mediclinic Vergelegen.
One test is particularly useful for both diabetes patients and their doctors. “Measuring glycated haemoglobin, (HbA1c), allows us to see how well a patient on treatment is controlled by this estimate of average glucose” says Dr Pretorius, “as it gives us an overview of how their blood glucose levels have changed (for better or worse) over the past few months, which allows us to see whether our treatment plan works.”
This test has been around for decades – but a new trend is emerging that makes effective diabetes management that much more accessible for patients across South Africa.
An HbA1c test can be conducted in a doctor’s rooms, but the blood sample then needs to be analysed, and in many hospital settings, this analysis can take days to be completed. “My practice is situated directly above a lab, so my patients have those results within the same day of testing,” he says. “But for those outside SA’s metropoles, especially in remote or rural areas, you could wait days or weeks for results.”
This is where point-of-care HbA1c testing comes in.
Generally speaking, point-of-care testing refers to any form of laboratory test conducted in the presence of a healthcare professional. Testing in this setting allows for quick and accurate results, which in turn encourages greater and more immediate dialogue between patient and doctor.
“The problem is access – if we have to test someone, wait for results, then advise them accordingly on how to adjust their course of treatment, that is time-consuming and frustrating,” Dr Pretorius says. “In the case of diabetes, a delay like that can have disastrous and even life-threatening implications.”
To understand how HbA1c testing works, Dr Pretorius explains that a red blood cell typically lives within the body for two to three months. “Haemoglobin is a protein within red blood cells that carries oxygen to cells and joins with glucose in the bloodstream,” he says. “When that happens, we say the haemoglobin is glycated, and that’s what this test looks for.”
A red blood cell typically contains approximately 270 million haemoglobin molecules. “The HbA1c test gives us a result as a percentage: if it’s higher than 6.5%, or 48 mmol/mol, that’s cause for concern. But this is an average, over the course of a blood cell’s lifespan – so even if your glucose level is normal today, this test shows us how well a patient has been able to control his or her blood sugar level over the past few months.”
A recent study in the Journal of Diabetes Science and Technology, which examined data collected from 1999 to 2016, showed that HbA1c at the point of care improves clinical outcomes, facilitates patient education and motivation and may, in future, help detect cases of prediabetes and diabetes earlier, potentially preventing diabetes-associated complications.
In rural areas, where doctors often see patients in rooms or clinics far removed from equipped blood laboratories, an accurate point-of-care HbA1c test device could save lives. “Many diabetics benefit from at-home, finger-prick blood glucose tests, but point-of-care HbA1c testing devices are specifically for use under a doctor’s supervision,” says Dr Pretorius. “If they are used correctly they are a great innovation.”