Type I diabetes (insulin-dependent diabetes mellitus) is the most common endocrinology disorder, with onset typically occurring in adolescence. It is thought to be an autoimmune disorder that results in pancreatic beta cell destruction and the eventual loss of all insulin production. Insulin regulates blood levels of the sugar glucose and allows glucose to enter cells from the bloodstream, where it is absorbed and used as energy. Patients with type I diabetes must administer exogenous insulin daily in order to maintain normal blood glucose levels. In type II diabetes (non-insulindependent diabetes mellitus), insulin continues to be produced, but it is either produced in insufficient amounts to maintain normal blood glucose levels, or there is insulin resistance, and the body does not properly utilize insulin.
Approximately 5% to 10% of Americans with diabetes are diagnosed with type I diabetes, which occurs in approximately 1 in 500 to 600 children in the United States and in the range of 0.6 to 2.5 in 1,000 children worldwide. The disease appears to occur equally in females and males, with peak onset of the disease typically around puberty, although it can be diagnosed through middle adulthood. Type I diabetes appears to occur in individuals with a genetic predisposition, accompanied by an environmental stressor. According to the American Diabetes Association (ADA), presenting symptoms at the time of diagnosis of type I diabetes include polyuria (increased urination), polydipsia (excessive or abnormal thirst), weight loss accompanied by dehydration as well as glucose levels of over 126 mg/dl (i.e., milligrams of glucose per 100 milliliters of blood) while fasting, or a random level of blood glucose over 200 mg/dl. The incidence of type II diabetes, previously considered a disorder of adulthood, has recently increased in younger children and appears related to increased rates of childhood obesity. In fact, type II diabetes currently accounts for approximately 10% to 20% of new diabetes cases in younger people. The incidence of type II diabetes is higher in African-American, Native American, and Latino populations.
In an effort to maintain near-normal blood glucose levels (between 80 and 120 mg/dl), daily blood glucose monitoring, administration of exogenous insulin, proper diet and meal planning, as well as exercise, are central to the treatment of type I diabetes. The goal of treatment is to maintain blood glucose levels close to the normal range in order to reduce the risk for complications. Blood glucose levels are measured several times daily (typically before meals and at bedtime) with a glucometer, which measures blood glucose from droplets of blood. In addition, a glycosylated hemoglobin (HbA1 ) test provides patients with information about their average blood glucose level over the past 2 to 3 months and should be conducted quarterly at a doctor’s office. Exogenous insulin is administered two to three times per day via injections or via an insulin pump with an indwelling needle/catheter under the skin in an effort to restore glucose metabolism. Insulin doses are calculated by individuals based on their blood glucose reading from a glucometer at the time of an injection/infusion as well as based on the content of an upcoming meal. As an alternative to daily injections, the insulin pump can help maintain better metabolic control by its administration of small amounts of insulin continuously throughout the day, with larger amounts/boluses at meal times. The diet recommended by the ADA typically includes 45% to 60% of total calories from carbohydrates, 30% from fat, and 10% to 20% of calories from protein. Exercise is an important aspect of the treatment of diabetes, as it also affects blood glucose levels. For some children with type II diabetes, the disease can be managed by appropriate diet and exercise in an effort to lose weight, sometimes in conjunction with oral medications. However, children with type II diabetes frequently also require daily insulin therapy.
When abnormal blood glucose levels are detected, they must be corrected to avoid episodes of hyperglycemia (blood glucose levels in excess of 180 mg/dl), as well as episodes of hypoglycemia (blood glucose levels below 70 mg/dl). Hyperglycemia can result from excessive carbohydrate intake or an insufficient dose of insulin, and is characterized by extreme thirst and hunger, frequent urination, unusual weight loss, extreme fatigue, irritability, nausea, and sweet-smelling breath. Prolonged hyperglycemia can result in the production of ketone bodies and in severe cases can lead to diabetic ketoacidosis, a serious condition where the body has dangerously high levels of acids (i.e., ketones) that accumulate in the bloodstream. This can lead to severe dehydration, coma, or even death and typically requires hospitalization. Hypoglycemic episodes can result from a missed meal, too much insulin, or exercise and includes symptoms such as dizziness, nausea, sweating, trembling, and confusion from insufficient levels of blood glucose to maintain normal brain functioning. Hypoglycemia can result in seizures, coma, and even death if not treated.
Potential long-term complications of diabetes include nephropathy (kidney disease), neuropathy (nerve damage), cardiovascular disease (heart disease), skin and foot complications, as well as retinopathy, which can lead to blindness. These complications have been associated with longer disease duration as well as with poorer metabolic control (i.e., chronic hyperglycemia). The maintenance of near-normal glucose levels can decrease and delay the development of these complications. Children with diabetes also are at an elevated risk for various psychiatric problems, including eating disorders, depression, and anxiety. Furthermore, from a psychological perspective, type I diabetes has been associated with an increased risk for learning disabilities, particularly with an earlier age of disease onset. However, maintenance of near-normal blood glucose through treatment, including administration of appropriate amounts of insulin, proper diet, and adequate exercise, can allow patients with type I diabetes to lead a relatively normal life and avoid these potential consequences of the disease.
References:
- American Diabetes Association, http://www.diabetes.org
- Eisenbarth, S., Polonsky, K. S., & Buse, J. B. (2003). Type 1 diabetes mellitus. In P. R. Larsen, H. M. Krononberg, S. Melmed, & K. S. Polonsky (Eds.), Williams textbook of endocrinology (10th ed., pp. 1500–1504). Philadelphia: Saunders.
- Styne, D. M. (2004). Pediatric endocrinology. Philadelphia: Lippincott
- Williams & W Weich, T., & Sandberg, E. (2004). Diabetes mellitus, type 1. In T. H. Ollendick & C. S. Schroeder (Eds.), Encyclopedia of clinical child and pediatric psychology. New York: Kluwer Academic/Plenum.
- Wysocki, T., Greco, P., & Buckloh, M. (2003). Childhood diabetes in psychological context. In M. C. Roberts (Ed.), Handbook of pediatric psychology (3rd ed., pp. 304–320). New York: Guilford.