Treatment of diabetes
Type 1 diabetes must be treated with insulin. There are different types of insulin and different schedules and modes of delivery. Generally speaking, type 1 patients need a long-acting or intermediate-acting insulin to cover them for a 24-hr period regardless of food intake, plus a short-acting insulin to take care of glucose swings during meals. Examples of long-acting insulins are ultralente and glargine; intermediate-acting insulins are NPH and lente; and short-acting insulins are regular and lispro.
An insulin pump may be used in cases involving type 2 diabetes that does not respond to treatment or type 1 diabetes in which a patient does not follow her prescribed regimen. The insulin pump acts as a continuous insulin infusion. This is a device in which fastacting insulin is stored in a reservoir, and is connected by tubing to a needle inserted under the skin, usually in the abdomen. The pump is programmed to provide different basal rates of insulin infusion throughout the day and night. Patients have to monitor their blood glucose before meals and exercise and make adjustments over and above the basal rate (boluses). They also have to make adjustments by taking extra calories for low sugar reading (corrections). The insulin pump can provide smoother glucose control, but patients have to be extremely motivated in order to check their glucose up to 6-8 times daily. There is higher risk of low blood sugars because of tighter blood sugar control.
Currently, researchers are working on pancreatic islet cell transplantation for the treatment of type 1 diabetes. When successful, the procedure cures diabetes, but immune-suppressing drugs are required and can have toxic side effects. Sometimes the transplanted cells just do not last or they may be destroyed by the same autoimmune reaction that made the person diabetic in the first place.
Treatment of type 2 diabetes includes oral medication and/or insulin. The medication chosen depends on a variety of factors, such as how long the person has been diabetic, whether she is overweight or lean, and how high the blood glucose rises. There are different classes of oral medications. In general, there are medications that cause increased insulin output from the pancreas, such as the sulfonylureas (glyburide, glipizide, and others). Nateglinide also increases output from the pancreas but is shorter acting and may be helpful in patients with high blood sugars after meals. These medications can cause low blood glucose and weight gain.
A treatment known as metformin may help obese patients with insulin resistance and helps muscles use glucose while also reducing glucose output by the liver. It must be used with care in patients with kidney problems and congestive heart failure. Common side effects include gas and diarrhea, which are minimized when metformin is taken with meals. Weight gain is not a side effect, and some patients might lose some weight. Medications of the group thiazolidinediones (pioglitazone, rosiglitazone) are also effective in reducing insulin resistance. With these drugs, liver function must be monitored with blood tests. Weight gain and edema are common side effects so these medications cannot be used in severe heart failure. Finally, insulin remains an important medication in the treatment of poorly controlled type 2 diabetes, either when oral agents have failed or at any time that patients develop insulin deficiency.
The goal of diabetes treatment is to achieve optimal control of blood glucose, cholesterol, and blood pressure.
Regular exercise, attention to the feet and nails, and annual eye exams are excellent preventive measures. Regardless of what medication is used, the mainstay of diabetes treatment is always diet and exercise.
The American Diabetes Association dietary recommendations are as follows: carbohydrates should comprise 50% of daily calories, fat less than 30%, and cholesterol should be less than 300 mg daily. Of the fat, less than 10% of calories should be derived from saturated fat and greater than 10% from monounsaturated fat. Protein intake should be 0.8 g/kg body weight and dietary fiber intake should be between 20 and 35 g daily.
The care of diabetes often involves several team members: patient, physician, diabetes educator, nutritionist, podiatrist (foot doctor), ophthalmologist (eye doctor), and/or psychologist. Patients are required to monitor blood sugars by using a glucometer, a machine that uses special strips on which a drop of capillary blood is obtained by pricking the fingers or arm with a lancet (tiny needle). Capillary blood monitoring lets patients and their care providers assess glucose control and make adjustments in diet, exercise, or medications. See Table 1 for treatment guidelines.
|Table 1. Diabetes monitoring goals|
|HbAlc (%)—reflects 3-month average glucose||≤7%|
|Glucose before meals (mg/dl)||80-120|
|Bedtime glucose (mg/dl)||100-140|
|Blood pressure (mm Hg)||≤130 systolic,|
|LDL cholesterol (mg/dl)||≤100|
|HDL cholesterol (mg/dl)||≥45|
|Triglyceride (fat) (mg/dl)||≤150|
Prevention of complications
Two major studies in both type 1 and type 2 diabetes have shown that tight control of glucose reduces complications. The Diabetes Control and Complications Trial (DCCT) was a study of type 1 diabetic patients. It conclusively showed that intensive glucose control reduces microvascular complications. The DCCT showed a 60% reduction in the risk of developing neuropathy, 27% reduction in the risk of retinopathy, and 54% risk reduction in developing kidney damage. The United Kingdom Prospective Diabetes Study (UKPDS) was a large study of patients with type 2 diabetes. The UKPDS trial showed that intensive glucose control led to a 25% reduction in retinopathy and cataracts and 30% reduction in risk of early kidney damage. In patients with high blood pressure and type 2 diabetes, intensive control resulted in 30% reduced risk of stroke and 46% reduction in death.
Prevention of diabetes
The Diabetes Prevention Program was a study of persons at risk of developing type 2 diabetes. It showed a 58% reduction in diabetes with 30 minutes a day of moderate physical activity along with a 5-10% reduction in body weight. Metformin, too, reduced the risk of diabetes by 31% but was less effective in persons older than 45 years and in those with a body mass index greater than 35. There is no definite evidence that anything can be done to prevent type 1 diabetes. The Diabetes Prevention Trial used insulin in subjects at risk for type 1 diabetes, based on family history and other parameters, but this was not effective. In women with polycystic ovary syndrome, metformin taken before and throughout pregnancy reduces the occurrence of gestational diabetes from 31% of pregnancies to 3%. Metformin appears to be safe to for use in pregnancy. More research is being done on all forms of diabetes.