Diabetes Mellitus

          Diabetes is a metabolic disorder resulting from insufficient insulin production by the pancreas, an organ located behind the stomach.  Insulin is a hormone that is normally secreted into the bloodstream by the pancreas in response to sugars in the food we eat.  Insulin helps transport sugar from the bloodstream into the cells.  When insulin is lacking, the cells which make up the muscles and other tissues are deprived of glucose, a specific type of sugar, which is the body’s main source of energy.  The sugar then builds up in the blood resulting in a situation called hyperglycemia.  This is why diabetes is sometimes described as ‘starvation in the midst of plenty’.  The cells are starved, but there is plenty of sugar in the blood. 

Types of Diabetes:  

          Type I diabetes, formerly referred to as juvenile diabetes, is most often diagnosed in childhood or adolescence and requires insulin injections.  Type II diabetes, the most common form of the disease, can occur at any age, but is more likely to occur later in life and can often be prevented.  Prediabetes is a state where blood sugar levels are elevated, but not high enough to make a diagnosis of diabetes.  Without treatment, prediabetes will likely lead to Type II diabetes and the long term damage to various organs in the body may already have begun.  For the purposes of this article we will not include a discussion of gestational diabetes and will focus mainly on Type II diabetes. 

Causes:  

          Type I diabetes results when the immune system attacks and destroys insulin producing cells in the pancreas.  It is unclear why this happens, but genetics and viruses may also play a role.  Prediabetes and Type II diabetes occur when the cells become resistant to the action of insulin and the pancreas is not able to compensate for this by increasing insulin production.  Inactivity and excess abdominal fat play a role in the development of Type II diabetes. 

Incidence: 

          A recent study by health insurer United Health Group reported that more than half of Americans will have diabetes or prediabetes by 2020.  Currently 26 million Americans have diabetes and 67 million have prediabetes.  More than 60 million Americans are not aware that they have diabetes.  By 2020 it is estimated that diabetes will account for 10% of the total health care costs in the United States or $500 billion annually.  The average cost of care for a person with known diabetes in 2009 was estimated to be $11,700 compared to $4,400 for a non-diabetic.  For a diabetic with complications the annual cost jumped to $20,700. 

Symptoms: 

          Some of the common symptoms with all types of diabetes include increased thirst, frequent urination, hunger, unexplained weight loss, blurred vision, wounds that heal slowly and frequent infections.  Some of these symptoms are a direct result of the sugar (fuel for the body) not getting into the cells (weight loss, hunger) and the resulting backup of sugar in the blood (osmotic diuresis).  A person with prediabetes may not have any symptoms. 

Risk Factors: 

          Family history and exposure to a viral illness may play a role in the development of Type I diabetes.  The risk factors for Type II diabetes include increased weight, inactivity, family history, and age.  The more fatty tissue you have the more resistant your cells become to insulin.  Lack of exercise means that less glucose is used as energy, while an increase in physical activity helps control weight and makes cells more sensitive to glucose.  Blacks, Hispanics, American Indians and American Asians have an increased incidence of diabetes.  As we get older the incidence of Type II diabetes increases due to a decrease in our activity level and an increase in weight.  In recent years, however, the incidence of Type II diabetes has been increasing dramatically in children, adolescents and young adults. 

Complications: 

          The short term complications of diabetes include hyperglycemia, ketoacidosis and hypoglycemia all of which can be life threatening.  We will focus on the long term complications, which occur gradually and are largely the consequence of the effects of diabetes on the blood vessels, both large and small.  The effects of diabetes on the cardiovascular system include an increased incidence of heart attack, stroke and narrowing of large arteries due to atherosclerosis.  Other complications include nerve damage, kidney disease, and blindness.  

Diagnosis: 

          A diagnosis of diabetes is made when the fasting blood sugar is greater than or equal to 126 ng/dl on two different occasions.  A level of 100 to 126 is considered prediabetes.  Another blood test called the Hemoglobin A1c can also be used to make the diagnosis.  A level of less than 5.7 is considered normal, a level of 5.7 to 6.4 is considered prediabetes and a level greater than 6.5 is considered diabetes. 

Prevention and Treatment: 

           There is no way to prevent Type I diabetes and it can only be treated by administering regular insulin injections.  Type II diabetes may be prevented by maintaining your ideal weight and getting sufficient exercise.  Treatment includes diet, exercise and oral medications, although sometimes insulin injections may be necessary.  Regular follow up with your healthcare provider is essential and should include routine eye exams and foot care and control of blood pressure and cholesterol levels.  Regular screening for asymptomatic patients should include children who are overweight and have other risk factors for diabetes, overweight young adults and all adults over the age of 45.  A diagnosis of prediabetes should be considered an early warning and an opportunity to take action before diabetes develops.