Diabetes Mellitus: Diagnosis and Treatment

Diagnosis

• The examination begins with a medical history and a physical examination.
  
• Blood glucose testing will be performed. Testing may be done either randomly, fasting, or as part of a glucose tolerance test, which measures blood glucose after the patient has ingested a sugary test syrup.
• In patients with diabetes, a blood test for hemoglobin A1c levels can be used to follow the adequacy of blood sugar control. It provides a fairly accurate measurement of the average blood sugar during the previous two to three months. Risk of complications is lower in patients who maintain lower A1c values.
• In some patients, type 1 diabetes can be confirmed by blood tests that identify antibodies directed against the pancreas. However, there are no tests for type 2 diabetes beyond measurement of blood sugar.
• Screening for gestational diabetes is a routine part of prenatal examinations. Screening typically occurs between 24 and 28 weeks of gestation and involves a similar blood sugar test as with the other types of diabetes.

Treatment

Dietary and lifestyle interventions are important for patients with all types of diabetes mellitus (see Nutritional Considerations). Education for diabetes self-management, which includes self-monitoring of blood sugar, is an important component of treatment.

For all types of diabetes, good blood sugar control decreases the risk of complications. It is important to be aware that certain medications (e.g., beta-blockers, steroids, thiazides diuretics, and oral contraceptives) can cause high blood sugar.

Type 1 Diabetes

Type 1 diabetes requires treatment with insulin injections. Insulin is available in several forms:

• Long-acting insulin can be administered once daily.
• Regular insulin or fast-acting insulin are quick-acting and can be administered before meals to curb the blood sugar elevations that occur after large meals.
• Fast-acting, inhalable insulin was approved for use in adults in 2006. However, its long-term safety remains unclear.
• Pramlinitide may also be injected at mealtimes along with fast-acting insulin. It reduces the elevations in blood sugar that occur with meals and suppresses appetite, which may lead to weight loss.

Type 2 Diabetes

There is a menu of medication options available to treat type 2 diabetes. Some people will require insulin, but it is common, especially in the early years following the diagnosis, to use one or more oral medications. The choice is based on factors such as effectiveness, expense, and other health problems that may be improved or worsened by one medication or another. It is important to know the name, dose, action, and possible side effects of any pills that have been prescribed. Below is a brief summary, with costs based on an online pharmacy search. Consult your pharmacist or your health care provider for more information.

The most commonly used oral medication is metformin (Glucophage). This pill works primarily by decreasing the liver’s production of glucose. Common side effects are stomach cramps, loose stool, and flatulance, but these often go away over time. This drug should not be used by people who have liver or kidney problems, both of which can be checked with simple blood tests. It also should not be used in people over 80 years of age, those who have any heart failure, or those who use alcohol. Metformin by itself will not generally cause blood sugar levels to get too low, and it works as something of an appetite suppressant. The average cost is about $60/month.

The largest and oldest group of drugs for diabetes work by helping the pancreas to make more insulin. Some common examples include glipizide (Glucotrol), glyburide (Diabeta, Micronase, or Glynase), and glimepride (Amaryl). The pills should be taken at lower doses in those with kidney problems and should generally not be used by people who are allergic to sulfa. The most common side effect is low blood sugar, which can sometimes cause people to feel hungry and eat more, which can cause weight gain. Another problem with these pills is that, for most people, they stop working after a few years. In some people, they can increase the risk of sunburn. The prices can range from $10 to $110/month.

Two more recent additions also help the pancreas to make more insulin. These are nateglinide (Starlix) and repaglinide (Prandin). These only last a few hours, so they must be taken before each meal. These pills may cause low blood sugar, but are less likely to do so than some other medications because they last for such a short time. They work best early in the disease process. The cost can range from $130 to $230/month.

Some medications work to by slowing down the digestion of carbohydrate. These include acarbose (Precose) and miglitol (Glyset). These must be taken with the first bite of food at each meal. They commonly cause abdominal pain, diarrhea, and flatulence. Low blood sugar can occur, and if does, it must be treated with pure glucose tablets or gel, or milk with lactose, since the medication blocks other carbohydrates, such as juice. The cost is around $110 to $160/month.

Another group of medications makes the muscle cells less resistant to insulin. These include pioglitazone (Actos) and rosiglitazone (Avandia). These pills should not be used in anyone with an abnormal liver function blood test or a history of heart failure. By themselves, these pills will not usually cause low blood sugar, but they do tend to cause weight gain and fluid retention. They cost around $170/month.

One of the newest types of medications for diabetes works to enhance the body’s incretin system, which helps to regulate blood sugar levels. The only drug is this class so far is sitagliptin (Januvia). It works best early in the diagnosis, and does not cause low blood sugar or weight gain. However, it costs about $150/month.

If the medication you take is one of the ones that can cause low blood sugar, you should be aware of the signs and symptoms, and be prepared to treat it if it occurs. If blood sugar levels get too low (usually below 80, or whatever your health care provider feels is too low for you), you may feel the way you would if you went too long without eating. You might develop a headache or feel irritable or anxious. Other common symptoms are dizziness, sweating, shaking, and/or a change in vision. If left untreated, blood sugar may continue to drop, and can cause slowed reflexes, unsteadiness, and possibly loss of consciousness.

Low blood sugar can occur from certain diabetes medications if you go too long without eating, or eat less than usual, or if you are significantly more active than usual. It is important to know if the medication you take for diabetes can cause low blood sugar. If so, be sure to always carry a treatment, such as a small juice box, or three to four glucose tablets, or a roll of Lifesavers. These will help to quickly bring your blood sugar level back up to normal, but will not last very long, so have a snack or a meal within 30 minutes of a low blood sugar event to prevent it from happening again.

As you change to a healthy, low-fat, plant-based diet, those medications may become too strong and you may start to have some of the symptoms of low blood sugar described above. This does not mean the diet is bad! This may be a sign that you no longer need as much medication.

Talk to your health care provider about your medication(s) if you experience low blood sugar.

Gestational Diabetes

Dietary changes are the first-line treatment (see Nutritional Considerations). If dietary changes are not sufficient to achieve normal blood sugar, insulin injections should be considered.

Role of Exercise

A sedentary lifestyle is associated with increased risk for high blood sugar and diabetes. In persons with established diabetes, exercise reduces blood sugar levels. Exercise also reduces cardiovascular complications of diabetes, including high blood pressure, heart disease, and inflammation. Exercise alone has little or no effect on body weight.

Women who either have or are at risk for gestational diabetes can also benefit from exercise. Walking or upper-body exercises (but never while lying on the back) may reduce the risk of gestational diabetes and help lower blood sugar levels to the normal range. In women with gestational diabetes, exercise has been found to be a useful strategy for helping to maintain blood sugar within the normal range, and for helping these women to control blood sugar without the use of insulin. However, exercising must be stopped if contractions occur.