Diabetes Mellitus Health Article

MONITORING

Self-monitoring of blood glucose is integral to modern diabetes therapy. A lancet is used to obtain a small drop of blood, which is placed on a reagent strip and inserted in a small battery-powered meter. The meter reports the blood glucose level in less than a minute. Results of self-monitoring of blood glucose are used to guide adjustments in diet, exercise, and medications, for the monitoring and treatment of hypoglycemia, and in the home management of intercurrent illness.

INCIDENCE AND PREVALENCE

The number of people developing diabetes and the number of people with diabetes are increasing worldwide. In 2000, it was estimated that 154 million persons, or 4.2 percent of the world's population, twenty years of age and older had diabetes. By the year 2025, it is estimated that nearly 300 million persons, or 5.4 percent of the world's population, twenty years of age and older will have diabetes. The major part of this increase will occur in developing countries due to the aging of the population and increasing urbanization (associated with increased body weight and decreased physical activity).

In 1994, there were 939,000 Americans newly diagnosed with diabetes, with a disproportionate number among the elderly and minority populations. The incidence of diagnosed diabetes was3.61 cases per 1,000 persons per year in 1994 (see Table 2).

In 1994, about 8 million persons in the United States (3.1 percent of the population) reported that they had diabetes. The prevalence of diagnosed diabetes increases with age (see Table 3).

MORTALITY

Diabetes is the seventh leading cause of deaths in the United States. The highest death rates due to diabetes are observed in older Americans and in minority populations. Death certificates underestimate diabetes mortality because of underreporting of diabetes. Only about 10 percent of people with diabetes who die have diabetes listed as the underlying cause of death on their death certificates, and only about 40 percent have it listed anywhere on their death certificates. Diabetes was the underlying cause of death for approximately 57,000 Americans in 1994, and diabetes was recorded on the death certificate of approximately 182,000 Americans. In 1994, black women had the highest death rates due to diabetes, followed by white women and men. That same year, 44 percent of all diabetes-related deaths (80,000 deaths) had cardiovascular disease listed as the underlying cause. Of these deaths, approximately 60 percent were caused by ischemic heart disease and 15 percent by stroke.

COMPLICATIONS AND COMORBIDITIES ASSOCIATED WITH DIABETES

Diabetic Ketoacidosis (DKA). Ketoacidosis is an acute metabolic complication of diabetes associated with hyperglycemia, nausea, vomiting, abdominal pain, dehydration, ketonemia, and acidosis. In 1994, DKA was the primary diagnosis for 89,000 hospital discharges and a listed diagnosis for 113,000 hospital discharges. Clinical trials have demonstrated that improved education in self-management and improved access to care can prevent up to 70 percent of DKA hospitalizations.

Adverse Outcomes of Pregnancy. Each year in the United States, type 1 diabetes complicates approximately 7,000 pregnancies and type 2 diabetes complicates approximately 12,000 pregnancies. Up to 1,700 infants (9%) of mothers with pregnancies complicated by diabetes (in the U.S.) are born with birth defects affecting the brain, spinal cord, heart, kidneys, and skeleton. Clinical trials have demonstrated that with intensive glycemic control before conception and during the first trimester, the incidence of major birth defects may be reduced to 2 percent, the rate that occurs in infants of nondiabetic mothers.

Diabetic Eye Disease. Diabetes is the leading cause of new cases of legal blindness in Americans between twenty and seventy-four years of age. As many as 40,000 Americans become blind each year as a result of diabetes. In type 1 diabetes, most legal blindness is due at least in part to diabetic retinopathy. Timely diagnosis and appropriate laser treatment can prevent up to 90 percent of blindness due to diabetic retinopathy. In type 2 diabetes, cataract, glaucoma, and senile macular degeneration are more frequent causes of blindness.

Diabetic Kidney Disease. Diabetic nephropathy is characterized by hypertension, proteinuria, and progressive renal insufficiency. Diabetes is now the leading cause of end-stage renal disease (kidney failure requiring dialysis or kidney transplant for survival). In 1997, over 33,000 Americans developed end-stage renal disease due to diabetes. Early detection, aggressive blood pressure control, and treatment with angiotensin-converting enzyme inhibitors can reduce the progression of diabetic nephropathy by about 60 percent.

Amputations. Diabetic neuropathy, peripheral vascular disease, and infection predispose people with diabetes to gangrene and amputations. More than half of all nontraumatic lower extremity amputations (LEAs) occur in people with diabetes. In 1994, there were approximately 67,000 diabetes-related hospital discharges with LEA reported as a procedure in the United States. Clinical trials have demonstrated that early detection of insensitive and deformed feet and multidisciplinary foot-care programs can reduce the rate of amputation by more than 50 percent.

Cardiovascular Disease Cardiovascular disease (CVD) is the leading cause of morbidity and

Table 4

mortality in people with diabetes. Stroke, heart attack, and peripheral vascular disease are two to four times more common in people with diabetes than in people without diabetes. In 1994, there were 1,144,000 diabetes-related hospital discharges that had CVD listed as the primary discharge diagnosis (see Table 4). Part of the increased incidence of cardiovascular disease in people with diabetes is due to the greater prevalence of cardiovascular risk factors, including hypertension, dyslipidemia, and cigarette smoking. Clinical trials have demonstrated that pharmacologic treatments for hypertension and dyslipidemia are as effective, if not more effective, in people with diabetes compared to people without diabetes.