"Type 2 Diabetes: The Genetic Trojan horse in HbA1c testing"
About: South Australia South Australia
Posted by AngusMac (as ),
I have been a type2 diabetic for 27 yrs. I was hospitalised with ketoacidosis for 7 days.
I was referred to an Endocrinologist, who told me to come back every 2 yrs. In the late 90's I began to notice high BGLs and would go to the GP, who would send me for a 12hr fasting HbA1c (A1c for short) test. Due to moving house etc I saw quite a few GPs. All told me that my A1cs were great control. When I asked for a referral back to Endocrinologist I was told I did not need one!
As I got more lethargic, I couldn’t understand why I was continuously being told that I had great control. I decided to join a 5yr research program for diabetics at a major hospital, hoping that I would get some answers. On 2 occasions I was finger pricked with an A1c meter (which I did not know existed. I was told that I wasn’t a diabetic and I was refused my appointments with the Hospital Dietitian.
At the time I taught Accreditation Standards. I eventually lost my job as I could not concentrate and was totally lethargic.
In 2008 I met a young GP who I believed was puzzled with my great A1cs results. I asked him for a referral to an Endocrinologist which he agreed to. On relating my experiences, he brought out 2 meters. I recognised the BG Meter but not the A1c meter. I remembered he explained that my 12hr fasting A1cs was in fact for Blood chemistry not A1c as this can be done at any time. It took all of 10secs to finger prick me and it seemed that he immediately saw that the readings did not relate. I was then given a Fructosamine test which verified his diagnoses that I had Variant Haemoglobin or the 'Umbrella' term Haemoglobinopathies.
I had just accepted these A1c tests on 'face value' as I had never been taught about the chemistry of A1c as HbA1c is generally referred to as the 'Gold Standard Test' in Diabetic management. In my experience (based on this test) my GPs have either put me on medication/insulin or left as is due to 'great control'.
Putting my Quality Assurance 'hat on' I back tracked to find why it was not picked up. In my opinion I believed it was not picked up because the lab report, showed on page 1--- A1c --4-0 and 4.1 and underneath a table '7% the Goal' --- less than 6 non diabetic level however on page 2 my fasting glucose was 15.5 mmols. To me it appeared that my GP had only been reading page 1 when I went for my A1c results. The GPs I have spoken to did not know of the confounder of A1c testing.
The nurses and endocrinologist I was in contact with at the hospital trial had used A1c meters in isolation and declared me a non-diabetic.
Heamoglobinopathies are rare in caucasins within Australia but are somewhat more common in people from the following ethnic backgrounds (which I fit into as a Scot with Irish ancestry):- Southern European (Greek; Italian; Maltese; Cypriot; Spanish), Middle Eastern; African; Chinese; South East Asian; Indian Sub-Continent; Pacific Islander; New Zealand Maori; South American and some Northern Western Australian and Northern Territory Indigenous communities as quoted in a letter I received from the Minister for Health in South Australia.
It is my belief that Diabetes educators, GPs and nurses etc. in the Diabetic area should be made aware of Haemoglobinopathies as I think that those who ‘fall through the net’ of A1c’s ‘exception to the rule’ could, like me, not be medicated correctly, which in my case lead to earlier complications.
From my experience I think that a diabetic is only as good as their self-management skills will allow so I would suggest other diabetics write down their results of A1c tests and then compare them with their BGLs and see if they match, then ask their GP for a Fructosamine test.