It's estimated today that diabetes mellitus affects 15% of all people over the age of 65 years old in developed countries world wide. Over 15 million people in the United State are diabetics with 790,000 new cases being diagnosed every year. This figure represents approximately 5.9% of the population of the U.S. Trends in society have had a significant impact on the development of this disease. Obesity and decreased physical activity are major contributing factors to diabetes. As we move from an agrarian society to a technology based society, our opportunity for physical labor and recreational exercise decreases. Also, particular ethnic groups (Native American, Hispanic and Blacks) show a particular propensity for this disease.

The morbidity and mortality of diabetes mellitus is staggering. Diabetes is the leading cause of blindness, kidney disease and non-traumatic limb loss in the world. Approximately 67,000 amputations are performed in the U.S. each year as a result of diabetic complications. Diabetics are also at a significantly higher risk for strokes and heart attacks. As a result of the increased morbidity of diabetes resulting in a high utilization of healthcare services by diabetic patients, our healthcare system is significantly taxed. It is estimated that the cost of treating diabetic patients and their complications in the US alone is over $98 billion dollars a year.

The classification of diabetes mellitus is defined by The American Diabetic Association (ADA). The following are the most contemporary definitions of DM;

Type 1 - Describes all causes of loss of blood sugar due to failure of the beta cells of the pancreas. Previously referred to as juvenile or insulin dependant diabetes.

Type 2 - Characterizes all metabolic abnormalities including insulin resistance and impaired insulin secretion. Previously referred to as adult onset or non-insulin dependant diabetes. Type 2 DM accounts for 90-95% of all new cases of diabetes.

Complications of diabetes mellitus are dependant upon the long term management of blood glucose (BG) levels. Poorly controlled BG results in destruction of the smallest of the blood vessels in the body called the microvasculature. These small vessels supply blood and nutrition to many of the organs of our body.

Most blood vessels have a central layer of muscle that can respond to pressure changes. As a result, the blood vessel is elastic in nature and able to adapt to change, such as exercise or transient high blood pressure. The increased load of carrying a more viscous fluid (blood laden with heavy sugar water) forces the musculature of the vessel to be 'on the job' at all times, and over time forces the vessel to be less able to respond to change. The result is that the vessel hardens (arteriosclerosis) and is less able to carry blood. The nutrients needed to heal the skin and soft tissue are now denied to the organ, making normal daily function particularly troublesome.

The organs most effected by the microvascular changes of DM are the eye (retinopathy), the kidney (nephropathy) and the peripheral nervous system (peripheral neuropathy), especially the leg and foot. Complicating factors in DM that may make the disease more difficult to treat include obesity and smoking.

The Foot and Diabetes

Many of the complications of DM effect the foot. As previously mentioned, the impact of DM on health, and in particular the foot, is immense. Subsequently, diabetic foot care is a critical part of overall diabetic care.

The combined effects of diabetic peripheral neuropathy and impaired circulation create a challenge for all diabetics. Many of the irritations of the skin that we would take for granted cannot be felt by a diabetic due to their peripheral neuropathy. Many diabetics fail to notice these problems until significant damage has occurred. Many will find drainage on a sock which is the result of a blister or ulceration.

Wound healing is also impaired in diabetic patients. In addition to the loss of normal blood flow to the foot, normal wound healing is compromised. The normal cellular and chemical responses of the body are unable to address diabetic wounds. Ulcers of the foot are a common complication in diabetic patients. Ulcers create a portal for infection which can effect both the soft tissue of the foot and the underlying bone.

New methods of wound care are always appreciated, but some of the tried and true methods still prevail as the most important. Debridement of diabetic foot wounds and counseling in effective footwear is a must. Your podiatrist and pedorthist should be a permanent member of your healthcare team. In addition to basic wound care, many adjunctive therapies have become popular over recent years including hyperbaric oxygen, growth factors, bioengineered tissue equivalents and electrical stimulation.

Another complication of advanced diabetes is a gradual shut-down of the autonomic nervous system. The autonomic nervous system is the portion of our nervous system that functions without our knowledge and regulates bodily functions such as salivation, bowel motility and perspiration. With advanced diabetes, the autonomic nervous system and its' ability to regulate perspiration of the foot is impaired. As a result, the skin of diabetics

Diabetic foot infections are obviously a challenge to treat. The complexity of impaired wound healing, peripheral neuropathy, poor circulation and dysfunction of the nervous system is a challenge for all physicians.

By far the most important method of caring for foot ulcers and infections is prevention and careful regulation of blood sugar levels. The tools of prevention are education and awareness. The following are tips for daily diabetic foot care.

1. Visually inspect the foot when the socks go on and when the socks come off. With a slow progressive loss of sensation due to peripheral neuropathy, the eyes become the next most effective tool to assess the status of the skin on a regular basis. If you can't see the bottom of the foot, put a mirror on the floor.

2. Frequent changes of shoes and socks (2-3 times/day). If you have a pressure point in a particular pair of shoes that could effect the skin, change the shoes. There's no simpler way to be kind to the feet.

3. Apply skin cream on a daily basis to the feet. Whether it's an over-the-counter or prescription skin softener, do it every day. Dryness is a major source of diabetic foot infections.

4. Wash and dry between the toes on a daily basis. The best location for bacteria to congregate on the foot is in between the toes. If you can't reach them, have someone else do it for you on a regular basis.

5. Treat fungal infections. Many fungal infection look like dry skin and can promote soft tissue infection. If you have a dry skin problem that does not respond to skin softeners, seek the help of a qualified podiatrist.

6. Make sure your shoes are your friends. It's well worth the time, effort and money to be sure that your shoes are not going to cause harm. Blisters and calluses in advanced diabetes can result in significant complications. Don't cheat yourself by buying inexpensive shoes. Seek the help of a certified Pedorthist.

7. When questions arise, don't wait. Act. Seek the help of your family physician or podiatrist.

Symptoms: Patients with hyperglycemia (elevated blood sugars) usually present with the symptoms of frequent urination (polyuria) and thirst (polydypsea). Recent onset diabetics also notice an increase in the number of times they urinate each night (nocturia). Elevated levels of glucose in the urine results in an attempt by the body to dilute the urine in the kidney with more water from the body (osmotic diuresis). This results in excessive urination. As a result of excessive urination, diabetics will have a frequent thirst an a need to drink increased amounts of fluids. Chemical imbalance can occur as a result of osmotic diuresis. Other symptoms include fatigue, blurring of vision, irritability and weight loss.

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About the Author

Jeffrey A. Oster, DPM, C.Ped is a board certified foot and ankle surgeon. Dr. Oster is also board certified in pedorthics. Dr. Oster is medical director of Myfootshop.com and is in active practice in Granville, Ohio.