Range of blood sugar levels for diagnosing Diabetes Mellitus is: Fasting-126 mg per deciliter and Post Prandial (PP) (After meal)-200 mg per deciliter (100 ml). Normal range of blood sugar is: 100 mg per deciliter for fasting sample and 140 mg per deciliter for an after meal sample. The readings falling in-between the aforementioned values i.e. between 100 & 126 fasting and between 140 and 200 after meal denote a grey area called “Pre Diabetes” or “Impaired Glucose Tolerance” (IGT). People having IGT are at a greater risk of not only developing Diabetes in the future, but are also at a higher risk of developing heart disease. More about it later.
As long as blood sugar levels remain below 250 mg %, (say, 150 mg % fasting and 250 mg% PP), the patient is NOT likely to feel any symptoms of Diabetes Mellitus, which are: increased urine output, increased thirst, slow healing or non healing of wounds, progressive weight loss in the face of ravenous appetite & excessive eating, persistent feeling of weakness etc. Under these circumstances, Diabetes becomes a “silent killer” insidiously continuing to cause damage inside the body, with all outward appearances being normal.
Often, it is symptoms of Diabetes which bring a patient to a doctor and invariably, blood sugar levels of symptomatic patients are above 200 mg % fasting. With the help of medical intervention, in a few days blood sugar level comes down to the aforementioned “silent killer” range and symptoms by & large disappear. Patient feels quite happy and is lost to follow-up, ignoring the medical advice to further bring down blood sugar levels to at least ‘near normal’. An unfortunate fact is that this so called ‘mild diabetes’ damages small arteries throughout the body (microangiopathy), progressively cutting off blood supply to various organs, leading to permanent, irreversible damage leading to total destruction of these organs. Brunt of this damage is borne by such organs of the body which have an extraordinarily rich blood supply- i.e. heart, eyes, kidneys and brain (so called ‘target organs’) and the resulting damage is called ‘target organ damage’, (TOD), (as if rest of the body is not getting affected at all-fact is that entire body undergoes this damage, leading to acceleration of the ageing process). I repeat for effect: TOD is not reversible with any available treatment and no such treatment is likely in the coming many decades. As if this was not bad enough, another disturbing fact has been revealed by research findings: - microangiopathic damage does not bear a linear relationship with severity of Diabetes. Therefore, whether your diabetes is severe or mild, damage to small arteries continues more or less at the same rate. So much so, that this expression “mild diabetes” is an anathema to medical professionals, to the extent that if a medical student happens to mention it during his viva-voce examination, God only can help him!
By mid 80’s, another observation was made by experts: that even if blood sugar levels are consistently maintained within normal range, Target Organ Damage still takes place at a significantly higher level than in normal population. Further investigation revealed that in such patients, though blood sugar test reports were all normal, but Glycosylated Hemoglobin (HbA1c) was invariably higher than normal. HbA1c is a blood test, which reveals average blood sugar over the past four months. The inference is obvious: normally done blood sugar test reveals blood sugar level at a given point of time. But blood sugar fluctuates within a wide range throughout the day. Accordingly, in these patients, blood sugar was deemed to have remained above normal range for a major part of the day. HbA1c is expressed as a percentage and its normal range is between 4% and 6.2%. To find out the correlation of HbA1c with Target Organ Damage, a research study called UKPDS (United Kingdom Prospective Diabetes Study) which is by now quite famous was organized in England. In this study, more than 10,000 diabetics were enrolled in 1986 and they were treated and observed for ten years. The results, which came out in 1996, were very surprising: It was found that if HbA1c is more than 7%, TOD incidence rises very sharply. In the form of an arm of UKPDS research trial, an attempt was made to bring down HbA1c even below 7%, but it resulted in an unacceptably high incidence of hypoglycemia (when blood sugar level goes too low). Therefore it was decided by experts that practitioners should strike a balance by aiming to bring HbA1c level down to 7% and no further down, in the bargain risking some TOD in the long run, but keeping hypoglycemia at bay. Certain amount of TOD is still expected to take place, but it was considered unavoidable.
Since 1996, newer forms of medications have become available with the help of which; if the treating physician and the patient are determined and are ready to put in hard work and adequate resources; it is possible to bring down HbA1c even below 6%, eliminating the possibility of TOD altogether. The first & foremost requirement for achieving this miracle is a strong desire; firstly in the mind of the patient and secondly in the mind of the treating physician; to achieve this goal.
Now coming back to IGT; which was mentioned in the first paragraph above. Leave aside ‘mild’ Diabetes, TOD starts taking place during IGT itself. It is on record that 42% of TOD takes place before IGT becomes frank Diabetes, which generally takes five years or so. Maximum TOD during IGT takes place in the heart. Second, in order of frequency, sufferers are the kidneys. Diabetes induced kidney failure is not unknown during IGT. Experts are recommending that full fledged treatment of Diabetes Mellitus should be started in all earnestness at IGT stage itself. By now it should be quite clear to you as to why ‘mild’ Diabetes is more deadly than ‘severe’ Diabetes. To drive the point home more forcefully, I would like to mention here that ‘severe’ Diabetes is like an enemy who strikes openly, giving you a chance to defend yourself, whereas ‘mild’ Diabetes is like a guerilla fighter or like white-ants or termites, which cause total destruction silently. If you want proof (there is abundant proof available in medical literature; but nothing is like seeing for yourself), go to any Dialysis unit (Dialysis is done for kidney failure, as a temporary arrangement while the patient waits for kidney transplant operation) of any hospital and speak to patients there. You will find that more than two thirds of them shall be diabetics and a majority of them shall have been on treatment for diabetes for many years, with a fairly good control of blood sugar, but diabetes still destroyed their kidneys. But there will not be a single such patient whose blood sugar was being monitored using HbA1c as a parameter. Tragically most of them even do not know that Diabetes was the culprit! They think that kidney failure is another affliction which struck them, in addition to diabetes and a few other unrelated things like heart disease and hypertension etc. That; in most cases, all these are different manifestations of a common root cause is something they find really difficult to come to terms with, when informed!
Unfortunately, even in developed countries; forget about developing countries like ours; the aforementioned eye-opening and path-breaking research findings are not being put to good use. Even in USA, the percentage of Diabetics, whose HbA1c is being monitored; forget about achieving the targets; is abysmally low. Why? Even I do not have a clear answer, but I guess the reason is something like this: traditionally down the centuries, medical profession has been orientated towards relief from symptoms arising from various diseases and towards curing the diseases which produced those symptoms. Accordingly, physicians are identified as ‘healers’. But how can you heal a person of a disease which has not arisen as yet? After all, so called ‘mild’ Diabetes is not a disease in traditional sense of the word, as it is not giving the patient any symptoms. It is a clinical condition which can only be detected with the help of a blood test. It takes the form of a disease when TOD has taken place and due to that the patient starts getting symptoms; list of which is too huge to enumerate here; depending upon the organ involved. Therefore, sensitizing a diabetic to the possibility of TOD is an enormously difficult task. In rich western societies, they have many more resources than us; in the form of formally trained paramedical staff like Diabetes Counselors, Dieticians, and Exercise Instructors etc, all supported by adequate infrastructure and educational tools like audio-visual aids etc. (though end results still are dismal, sadly). But here in our country, your friendly neighborhood physician/ family physician is the all-in-one in most of the cases. Super-specialist doctors, in the field of Diabetes are too few, and their work load is so high and paramedical support so little, that they cannot spare enough time to enter into a detailed discussion on the subject with the patient and convince him regarding hidden dangers. A solution to the problem is that rather than we doctors chasing people to achieve HbA1c level of below 6%, the equation should be turned other way round, i.e. patients should specifically demand the end goal from us (for phonetic convenience of vernacularly orientated tongues, it is okay to call it GULUCOSE HB). For this they have to be ready to work hard to achieve the goal and their dedication to the cause should be complete. We, the medical professionals, shall be too happy to deliver.