Diagnosis
The diagnosis of insulin resistance implies a patient has a disorder in tissues related to an impaired ability to respond to the action of insulin. This leads to a situation where the pancreas produces extra insulin in an effort to overcome the resistance to insulin. This elevation in insulin is known as hyperinsulinemia, or high blood insulin. Insulin resistance is not the same as diabetes although it is considered an early form of diabetes. The main difference in the two disorders is that the person with insulin resistance is capable of producing excessive amounts of insulin to maintain blood glucose, whereas the diabetic patient can no longer produce adequate levels of insulin to control blood sugar. Insulin resistance can come about through more than one mechanism. Receptor defects and obesity appear to be independent risk factors that may appear alone or in combination. There appears to be a genetic link so a family history of adult onset diabetes is a risk factor. Hyperinsulinemia can also occur in situations where the body is overproducing insulin but the tissues aren’t technically resistant to the effects of insulin. This occurs most commonly in the setting of excessive sugar intake. Insulin is a hormone which causes changes in different cells throughout the body. Excessive hormones can cause changes in the appearance of individuals. Polycystic Ovary Syndrome and Syndrome X are labels to describe a common appearance among patients with high insulin levels and insulin resistance. Insulin resistance is the most likely the underlying metabolic abnormality in PCOS and metabolic syndrome X. There is a lack of unanimous consensus about appropriate testing and diagnosis which often confuses patients and doctors. Many tests focus on tissue resistance to insulin rather than the absolute level of circulating hormone. We have specialized tests designed to find these elevations in hormones, however the actual tests are generally not needed as most everyone can benefit from the lifestyle modifications that can effectively reverse the effects of excess insulin. Treatment results can be quite impressive and can lead to pregnancy without fertility medications in many cases.
Insulin Physiology
Insulin is secreted by the pancreas in response to glucose. Glucose transport into cells requires insulin. Insulin binds to a receptor on the cell surface and causes a signaling cascade that leads to uptake of sugar. When receptors do not process the signal appropriately, the blood sugar will remain elevated unless the pancreas makes more insulin. The elevation in serum insulin can have far reaching effects in the body.
Effects of High Insulin
Insulin can cross into another hormone pathway known as Insulin-Like Growth Factor 1 (IGF-1). Insulin and IGF-1 are responsible for interrupting ovulation, stimulating the uterine lining, and initiating the development of heart disease. Insulin and IGF can alter the metabolism and actions of androgens which lead to excess hair growth, alopecia, and acne. Insulin and IGF can directly and indirectly increase cholesterol and lipids as well as increase plaque formation seen in cardiovascular disease. Insulin and IGF-1 play a key role in fat storage. Hyperinsulinemia leads to a predisposition towards central obesity. Obesity in turn increases insulin resistance. This leads to a cycle of disease progression that can be resistant to diet and exercise alone.
Treatment
Treatment sometimes involves a three-fold approach. A diet designed to reduce the demand for insulin will lead to lower insulin levels. This can be combined with exercise for a treatment method that is successful in most patients. We have an easy to understand diet plan that can lower the demand for insulin. Exercise helps to alter proteins that reduce the effects of insulin on the body as well as help decrease weight. These effects together improve insulin resistance. Occasionally these to treatments are not sufficient and medications may be required. Insulin sensitizing drugs improve the signaling mechanism of insulin at the level of the cell and receptor. Our treatment approach will combine the medication with diet and exercise if necessary. Metformin in the proper dose can be an effective treatment by correcting the underlying abnormality associated with polycystic ovarian syndrome. Proper treatment allows many women to ovulate and become pregnant. The associated weight loss can be impressive and many patients are able to adapt a new way of life for long term health.
Side Effects
The most commonly used medication is metformin (Glucophage). 30% of patients may experience nausea, diarrhea, and abdominal bloating. Starting low and building up to the desired dose over several weeks may alleviate these problems. A metallic taste during initial therapy is reported in 3% of patients. 1 in 33,000 people taking metformin develop a build up of lactic acid (lactic acidosis). While this is fatal in 50% of cases, it is not likely to occur in someone without impaired liver or kidney function. Symptoms include: weakness, unusual muscle pain, trouble breathing, stomach discomfort, feeling cold, dizzy or lightheaded, and suddenly developing a slow or irregular heart beat. All patients on metformin should follow up regularly with a physician familiar with metformin. Metformin may be continued during the first trimester of pregnancy or longer, however patients must consult a physician regarding their individual case and risks.
For more information on polycystic ovarian syndrome (PCOS – PCO) click here.