This is the second in a series of articles written to address some of the metabolic problems one can encounter with the use of prednisone (a mainstay drug for most of us). Metabolism is defined as the chemical changes in living cells by which energy is provided for vital processes and activities and new material is assimilated.
In this article, I want to focus primarily on glucose metabloism and insulin resistance and a bit on weight and structural changes to the body on steroids.The next article will be a continuation of metabolic issues and we will discuss issues with lipid disorders provokes by both prednisone and vasculitis itself.
First of all, prednisone has many striking effects on the boday habitus (or body form). From the onset of taking the medicine a process of catabolism starts (catabolism is the breakdown of muscle). This is most striking in the quadriceps (thigh muscles), buttocks, and shoulder girdle (shoulder muscles and muscles in the upper arm). Many people on long term steroids develop very thin arms and legs. In contrast to this fat deposition and redistribution occur in strange places. Fat deposition occurs in the cheeks and temple area giving the classic moon face or the Charlie Brown face as I like to call it. Deposition occurs strongly across the trucal area (truncal obesity) and the upper thoracic area causing the proverbial 'buffalo hump'. The changes in the skin can cause striae or stretch marks. These changes in appearance altogether are known as a 'cushinoid appearance', referring to the classic appearance of a person with Cushings disease. Cushings disease is caused when the adrenal gland overproduces cortisol (prednisone like substance). The taking of steroids by mouth or by injection simulate the appearance of someone with Cushing's disease but when it is created by taking the medicine is it known as Cushings syndrome.
This process of breakdown of muscle and buildup of fat in unusual places is out of the control of the person taking the medicine. It is dose related and the higher the dose the more marked the body changes are. Some people are more resistant to these changes than others while some people are very sensitive to prednisone and even small doses cause marked changes in appearance. Remember, prednisone is a pro-obesity drug (it causes obesity).
One of the next things to occur is the process of insulin resistance. Again, some people are more sensitive to this process than others but almost all of us develop this to one degree or another. Insulin resistance is actually a precursor or forerunner to Type 2 diabetes.
Insulin resistance is defined as the following:
truncal obesity (fat deposition in the trunk area of the body)
hypertriglyceridemia (elevation of a type of blood fat)
increased BMI or body mass index (weight and height used to calculate and is more sensitive in measuring obesity than just weight alone)
increased waist to hip ratio_ (people with insulin resistance have more of an apple appearance than of a pear)
hypertension ( high blood pressure)
high serum insulin
A person with insulin resistance may not have every one of the criteria but usually have at least three. This process of insulin resistance is sometimes called Syndrome X. The significance of this syndrome is a) the propensity of developing full blown diabetes and 2) the striking increase of cardiovascular disease. Heart disease and cardiovascular disease start in this phase, long before the diagnosis of diabetes has been made or before blood sugars are ever abnormal.
Generally a person spends about ten years with insulin resistance prior to the development of diabetes, but this varies markedly.Steroids or prednisone intake markedly enhances insulin resistance and may speed up the progression to type 2 diabetes.
So what is this insulin resistance exactly? If you can envision little insulin molecules floating around in the blood stream, ready to bind to insulin receptors on the surface of the cells of the body. When they are able to bind then glucose is able to be taken up by the cells and processed for energy. In insuline resistance, the receptors on the cells are fewer in number and don't work as well. You can think of insulin and receptors like a lock and key mechanism. If there is no lock for this key to turn then things don't work. The body tries to compensate by increasing the amount of insulin in the body to help bind to the faulty and decreased number of receptors. Increased insulin levels help to start of the cascade of vascular disease and heart disease. This process occurs long before the glucose (blood sugar ) levels rise to an abnormal level.
Okay, now what do I do? I have to take medication to control my disease, the medicine is causing other problems - what do I do from here? First of all, just as in diabetes, weight loss and careful eating need to be the cornerstone of treatment. A diabetic type diet, limited in calories, fat and saturated fat and low in simple sugars and sweets needs to be started. Examples of foods that need to be avoided include desserts, sugary foods, soft drinks and limited in fruit juices. Fried foods, cheeses and marbled red meat need to be eaten sparingly. An increase in fiber intake is also helpful. Exercise, to the extent that you are able, is also encouraged. The advice of a dietician may be in order.
There is one study out there looking at the intake of chromium supplements to enhance sensitivity to insulin. Glucophage (metformin) may be taken even if the blood sugar is not elevated or only infrequently elevated.This is an excellent medicine to help control the process of insulin resistance. Actos and Avandia are other meds that can be use to help combat the process as well.
Get your physician to evaluate you for insulin resistance and formulate a strategy for you to help treat it. Rheumatologists are not always the ideal doctors (no offense to any rheumatologist) to treat this as it is not really the focus of their specialty training. If they are uncomfortable or uninterested ask your internist, family doctor or an endocrinologist for assistance. These type of doctors can also help treat any accompanying lipid disorders that may arise in conjucntion with Churg Strauss Syndrome and prednisone or steroid administration.
In the next article , I will discuss more on lipid disorders and vasculitis.None of these recommendations in this article are meant as a substitute for appropriate clinical exam (doctor exam) and evaluation.
God bless all of you and take care.
Carol Kavanaugh D.O.