Know the potential risks involving early insulin therapy
early insulin therapy for diabetes type 2 is encouraged by some physicians; but according to a study it may cause more harm then benefits. Insulin therapy controls your blood sugar temporarily on a daily basis, but it does not help your body’s own system of control to do its job.
Insulin therapy requires increasingly higher doses, and constant switching of different kinds of insulin. It does not preserve β-cells from becoming dysfunctional.
Better clinical outcomes in early diabetes have been seen with antihyperglycemic oral regimens such as Metformin and Glipizide. Other risk factors are episodes of severe hypoglycemia, increase in cardiovascular mortality, weight gain as well as the potential increased risk for specific cancers.
Excess insulin in the blood in rare cases can also lead to mitogenic activity a condition found in individuals with pseudoacromegaly a disorder in which acromegalic features develops. The complications of insulin injection are exacerbated by insulin resistance itself. For more information please read Early Insulin Therapy for Type 2 Diabetic Patients: More Cost Than Benefit
- Excess insulin in the system
In normal physiology or in persons without diabetes, β-cell insulin secretion is rapid and because insulin’s half life (how fast a drug is eliminated from the system) is ~5 min. There is a small lag time in the glucose regulatory system so insulin does not stay in the blood stream for a long time. When insulin is injected usual rapid assimilation which is found in normal individuals is canceled since subcutaneous injections are absorbed slower and without the aid of natural metabolic control. It is dependent on the type of subcutaneous injection site and other factors. This in turn creates a condition called hyperinsulinemia which simply means “too much insulin in the system at one given time” which is associated with tumor growth and other cell growth conditions throughout the body.
- Effect of insulin injections on cells
Insulin action on cells has two signaling pathways, one which regulates metabolic activity such as the absorption and use of sugars and the other to regulate cell growth, growth hormone, and other growth related functions. In a normal cell these pathways are balanced. When the cell is insulin resistant and external insulin by injections are used to overcome insulin resistance, growth activity will be over stimulated and the pathways become out of balance. Evidence suggesting this relationship come from studies in patients with pseudoacromegaly. This disorder develops acromegalic features in individuals who are markedly insulin resistant.
- Hypoglycemia and increased mortality
Until recently it was though that the prevalence of hypoglycemia associated with insulin therapy was low but recent long term clinical trials with patients treated with intense insulin regimen have shown the contrary. A recent long term clinical trial named Action to Control Cardiovascular Risk in Diabetes (ACCORD) showed a 15.9% increased for the intensive glycemic control to 5.0% to standard glycemic control. Another study Veterans Affairs Diabetes Trials (VADT) had a 21.1% for intensive insulin to 9.7% for moderate control group. Cardiovascular mortality was also greater in studies where subjects were treated with prandial insulin (insulin given before meals)
- Weight gain
Weight gain accompanies insulin treatment. The magnitude of the weight gain is influenced by these factors
- Level of the initial glycemic control
- Glycemic control achieved
- Duration of insulin therapy
- Type of insulin regimen used
- Oral agents used
In a study focused on normalizing A1c levels for 6 months of intensive multiple dose of insulin therapy, the mean weight gain was 8.7 kg. When adding oral agents it showed a 1.4% decrease in A1c and only 6.4 kg weight. The mechanism responsible for the weight gain in insulin treated patients is complex and can result in part from the decrease in glycosuria. Other forms of treatment like Metformin have shown to promote weight loss. The increase in weight is associated with a striking increase in waist circumference.
- Risk of cancer
Recently, there has been a growing concern with the association of a increase in the incidence of specific cancers and the type of therapy of type II diabetes. It has been well established that pancreatic, hepatobiliary, colon, and breast cancers occur in higher incidence in patients with type 2 diabetes than in control populations. The reasons for these associations may be multiple and may include obesity, hyperglycemia, insulin resistance, and a type of antihyperglycemic therapy. Chronic intense insulin treatment might facilitate cancerous growth.
Insulin therapy should start late in the diabetes treatment and only when no other resources to lower blood glucose levels are available. Type II diabetes is characterized by a progressive decrease in both β-cell mass and secretory function so that in most individuals absolute insulin deficiency occurs in the late states of the disease hence the need to delay treatment as much as possible. Our own insulin production has it’s unique metabolic process in the body and insulin we inject has a different action with its own set of problems which should be considered carefully weighing the benefits Vs. its adverse effects.
- Action to Control Cardiovascular Risk in Diabetes (ACCORD) Trial: Design and Methods
- Intensive insulin therapy in the medical ICU — not so sweet?
- Intensive insulin therapy and mortality among critically ill
patients: a meta-analysis including NICE-SUGAR study data
- Intensified insulin therapy and the risk of severe hypoglycaemia
- Early Insulin Therapy for Type 2 Diabetic Patients: More Cost Than Benefit
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