Hyperinsulinemia

[Guest guest]

The Insulin Resistance Syndrome

B. Marks,MD

University of Miami

School of Medicine

Reprinted with permission from: The Monitor, Vol 1. Number 3, Spring 1996. A

publication of the American Diabetes Association/Florida Affiliate,

Inc./Southeast Region.

Abnormalities in glucose and lipid (blood fats) metabolism, obesity, and high

blood pressure occur together commonly enough in the same individuals as to

suggest that they are somehow interrelated. In fact, this cluster of

abnormalities has come to be known as a syndrome, going by a variety of names,

including Syndrome X, the Deadly Quartet, and the Insulin Resistance Syndrome.

What seems to connect the various features of the syndrome together is something

called insulin resistance: that is, a reduced sensitivity in the tissues of the

body to the action of insuln, which is, importantly, to bring glucose into those

tissues to be used as a source of energy. When insulin resistance, or reduced

insulin sensistivy, exists, the body attempts to overcome this resistance by

secreting more insulin from the pancreas. This compensatory state of

hyperinsulinemia (high insulin levels in the blood) is felt to be a marker for

the syndrome. The development of Type II, or non-insulin dependent, diabetes

occurs when the pancreas fails to sustain this increase insulin secretion. It is

not clear how insulin resistance contributes to the presence of high blood

pressure, but it is clear that the high insulin levels resulting from insulin

resistance contribute to abnormalites in blood lipids—cholesterol and

triglycerides.

The importance of the Insulin Resistance Syndrome, or perhaps more accurately,

" The Pluri-Metabolic Syndrome " , lies in its consequences. The syndrome is

typically characterized by varying degrees of glucose intolerance, abnormal

cholesterol and/or triglyceride levels, high blood pressure, and upper body

obesity, all independent risk factors for cardiac disease. If one includes along

with the classic four features the commonly associated conditions of aging,

sedentary lifestyle, stress, smoking, and a dose of genetic susceptibility, then

a deadly web of increased cardiovascular (heart and blood vessels) disease risk

is woven. In fact, the presence of any one major feature alone substantially

increases the risk of heart disease, but when they occur together the risk is

magnified way out of proportion at the contribution of any one single factor.

This point was strikingly demonstrated by the PROCAM (Prospective Cardiovascular

Munster) Study, in which the relationship between various cardiac risk factors

and the incidence of heart attack over a four year period was examined in 2,754

men aged 40-65 years. The results showed that the presence of diabetes or high

blood pressure alone increased the risk of heart attack by 2.5 times. When both

diabetes and high blood pressure were present, the risk was increased 8 times.

An abnormal lipid profile increased the risk 16 times; when abnormal lipid

levels were present with high blood pressure and/or diabetes, the risk was 20

times higher.

Treatment for the described metabolic syndrome therefore aims at treating all

of: the features of the syndrome that exist in a given person.

The first step, then, is to identify those people who may be at risk for the

insulin resistance syndrome—people who are overweight, those who have a parent

or sibling with Type II diabetes, women who had diabetes which occurred during

pregnancy.

The second step, once one feature of the syndrome is identified, is to look for

the presence of others. So, if a patient has high blood pressure and is

overweight, a search for diabetes and lipid abnormalities should be part of his

or her comprehensive evaluation. And, it means prescribing treatment

(appropriate not just for the primary problem) but treatment which will

hopefully benefit, or at least not worsen, any of the other conditions which may

also be present. We refer to this as multiple risk factor intervention—treatment

aimed aggresively at reducing all cardiac risk factors which may exist.

Fortunately, this is easy! The same general recommendations that we give to a

person who has Type II diabetes, for example, in terms of a diet low in fat and

concentrated sweets, weight loss and maintenance of ideal body weight, regular

exercise, cessation of smoking, and moderation of alcohol intake, are

essentially the same recommendations we give to someone with high blood

pressure, high cholesterol, or simple obesity. And, when pharmacological

intervention is required, we can now choose between a variety of drugs—blood

pressure medications which improve insulin sensitivity and have no adverse

effects on blood lipids, blood sugar medicines which improve insulin sensitivity

and blood lipid levels, blood pressure treatments which may be particularly

beneficial for the kidneys of people with diabetes—and so on.

This approach to caring for people with the insulin resistance syndrome, that of

comprehensive evaluation and risk factor management, is essential if we are to

meet and overcome the real health danger which accompanies this constellation of

metabolic abnormalities—cardiovascular disease.

Hyperinsulinemia

The overproduction of inactive insulin is called hyperinsulinemia. Type-2

diabetes is usually a by-product of hyperinsulinemia, which causes the body to

overproduce required insulin because the insulin is not being used effectively.

Although Type-1 diabetics cannot produce insulin, they may also develop

hyperinsulinemia and become resistant to their insulin injections.

When too much glucose stays in the blood this is called diabetes. Insulin is

produced in the pancreas to help the glucose get out of the bloodstream into the

worker cells that need energy. Type 1 diabetes is caused because the pancreas is

too weak to produce enough insulin to help unlock the cell doors for the sugar

to enter. Type 2 diabetes is usually caused because the body is insulin

resistant.

In hyperinsulinemia, when the insulin is not doing its job properly the body

thinks that it has not released enough and it keeps on producing the insulin to

compensate for the seeming lack. Therefore it is possible to have high blood

sugar and too much insulin at the same time.

Hyperinsulinemia may be reversed by diet control. But if it is caused by other

complications, such as PCOS, the root problem must be tackled, first, before the

hyperinsulinemia can be brought under control. If not corrected hyperinsulinemia

will lead to diabetes.

---------------------------------