Type 2 diabetes used to be referred to as “adult onset” diabetes, but no longer. In recent years, the incidence among children and adolescents has exploded. Much of that surge is due to the dramatic increase in the last 20 years in the number of young people who are physically inactive and overweight or obese.
The statistics are sobering. An estimated 25.8 million people in the U.S., or about 8 percent of the population, have diabetes. That’s up from 2.5 percent of the population in 1980. Despite the increase of the disease among the young, older people are still the largest age group affected with nearly 11 million people 65 or older afflicted with diabetes. And about 1.9 million adults are newly diagnosed with type 2 diabetes every year.
But despite widespread attention to the diabetes epidemic, about one in three people who have diabetes — some 7 million people — have not been diagnosed and do not know they have it. And many of those who have been diagnosed are not getting adequate treatment. A quarter to a third of the people who have been diagnosed with diabetes fail to receive the medical care and medicines that research has shown to be effective.
Why is diabetes of such concern? For starters, diabetes more than doubles the risk of developing and dying of heart disease and other problems. Indeed, the condition is as potent a predictor and risk factor for heart disease and heart attack as are cigarette smoking, high blood pressure, and high cholesterol. In 2004, the latest year for which data is available, heart disease was a factor listed on 68 percent of diabetes-related death certificates among people 65 or older.
Diabetes also significantly raises the risk of a host of other problems. These include: stroke, nerve damage, kidney damage; damage to the eye as well as total blindness; impotence, poor wound healing, and susceptibility to infections that can worsen and require amputations of toes, feet, or part of a leg.
In addition, people with diabetes are very likely to have other dangerous health conditions. One study found that 47 percent of people with diabetes had two other heart disease risk factors (such as smoking, high blood pressure, and high cholesterol), and 18 percent had three or more.
Overall, diabetes is the seventh leading cause of death in the United States. It is also a leading cause of disability. Women have the same prevalence of diabetes as men, but they are much more likely to die from it. African-Americans, Asian-Americans, Hispanics, American Indians, and the indigenous people of Alaska are more prone to develop diabetes (due to genetic and environmental factors) and to become disabled or die from it (due to multiple factors, including that they are less likely to get good care).
The symptoms of type 2 diabetes tend to develop gradually over time and include:
- Blurred vision
- Frequent urination
- Numbness or tingling in your hands or feet
- Increased thirst and hunger
- Infections and slow healing of wounds
These symptoms can also be mild and/or intermittent for years. If you experience any of these — and especially if you experience two or more, for even a few days — you should see a doctor.
In the early stages of the disease, symptoms may be nonexistent. That’s unfortunate because the damage to organs occurs even in the absence of symptoms. For this reason, it’s important for people who may be at risk for diabetes to get their blood sugar levels checked regularly. Those at risk include:
- People 65 and older
- People who have a condition called metabolic syndrome
- People who are overweight or obese
- Anyone with a parent or a sibling who has diabetes
- People who are African-Americans, Hispanic-Americans, Asian-Americans, Native Americans, Pacific Islanders, or Alaskan Natives
- Women who have had diabetes during pregnancy or a baby weighing more than 9 pounds at birth
If you are in one of these groups and have never had a blood sugar check, get it tested as soon as possible.
There is a disagreement in the medical community about whether all adults should have their blood sugar checked periodically. The American Diabetes Association advises that everyone aged 45 and over have a blood sugar test once every three years. But the highly regarded U.S. Preventive Services Task Force says not enough scientific evidence exists to show that such broad screening has benefits or is worth the cost.
We think the decision rests with you and your doctor, and depends on an assessment of your overall health, risk factors, weight, and family history. Some doctors are inclined to check the blood sugar levels of most people over age 45 or 50, especially if they are 10 or more pounds overweight. Other doctors may be more conservative.
Blood sugar tests are inexpensive and easy, though they may have to be done a few times to yield a conclusive diagnosis. One type of test is done after an overnight fast. If your blood sugar is 126 milligrams per deciliter (mg/dl) or greater after being checked on two or three different occasions, you are considered to have diabetes. Another type of test can be done at any time (not just after an overnight fast). If this test indicates your blood sugar level is 200 mg/dl or above, you are considered to have diabetes.
Your doctor may also talk to you about a blood test known as “hemoglobin A1c” (pronounced hemoglobin “A,” “one,” “c”; usually abbreviated in print as HbA1c and often referred to by diabetes patients as “my A1c”). This is a commonly used test to evaluate blood sugar control after treatment is started. But your doctor may order this test to make the diagnosis in the first place. There’s more about this measure in the next section.
But proper treatment can keep people with diabetes healthy. In fact, all people with diabetes who receive proper and consistent care live a normal life, and can work and carry out daily activities.
Given that all the diabetes drugs have the potential to cause side effects and lifestyle changes have benefits to your health beyond controlling blood sugar, most doctors will recommend you try diet and lifestyle modifications first — before you try a drug.
Many people with diabetes, however, also have high blood pressure and/or elevated cholesterol, or have been diagnosed with coronary artery or vascular disease. If you are in this category, your doctor may prescribe a diabetes drug when you are diagnosed, along with diet and lifestyle changes and classes in diabetes self-management.
Indeed, so many people with diabetes have other conditions and heart disease risk factors that doctors commonly treat them as “multi-disease” patients whose care and various medications must be managed particularly closely. Because heart disease risk factors, including diabetes, take a cumulative toll, medical groups and physician organizations have set aggressive goals for people with diabetes who have multiple conditions. Table 1 below presents these.
The aim of treatment with lifestyle changes and medications is to get your HbA1c lower (and keep it low) and to reduce your symptoms. As mentioned already, the HbA1c test is the one your doctor will use to track treatment success (or failure). It measures glucose levels chemically bound to hemoglobin, a protein carried by red blood cells. Over time, high blood sugar levels cause more glucose to bind with hemoglobin, so a high HbA1c percentage indicates that blood sugar levels are high on average.
Many experts believe that an HbA1c level below 7 percent is associated with a lower risk of diabetes complications, such as kidney disease and eye disease that can lead to blindness. However, there is no definite proof that maintaining HbA1c below 7 percent helps prevent heart disease and premature death because most studies of the oral diabetes drugs have only looked at the affects on HbA1c for a year or less.
Although aiming for an even lower HbA1c level — below 6.5 percent — that’s closer to the range found in healthy people who don’t have diabetes has been promoted in the past, it’s now unclear whether that is better for most diabetes patients. In the largest, most well-regarded study of this issue, people with diabetes who achieved an average HbA1c level of 6.4 percent over 3.5 years had an increased risk of death and no reduction in heart attacks or deaths from heart disease compared with patients whose HbA1c was maintained at 7.5 percent.
Goals for People with Diabetes
Measures Recommended Goal
Fasting blood glucose 70-130 mg/dL
Post-meal (2-hour) blood glucose Below 180 mg/dL
Hemoglobin A1c (HbA1c) Below 7.0%
Total cholesterol Below 200 mg/dL
LDL (“bad”) cholesterol Below 100 mg/dL
HDL (“good”) cholesterol Above 40 mg/dL for men and 50 mg/dL for women
Triglycerides Below 150 mg/dL
Blood pressure Below 130/80 mmHg
* These goals may be individualized based on your specific health situation and circumstances.
Sources: American Diabetes Association; American Association of Clinical Endocrinologists; International Diabetes Federation; National Cholesterol Education Program; Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; recent studies.
Definitions: LDL= low-density lipoprotein cholesterol; HDL= high-density lipoprotein cholesterol; mg = milligrams; dl=deciliter of blood; mmHg = millimeters mercury.
Two other studies did not find an increased risk of death in patients who maintained their HbA1c below 6.5 percent. But these studies were consistent with the one described just above in that they also failed to show a reduction in cardiovascular events (like a heart attack) or deaths.
Given these results and the evolving science, the American Diabetes Association and other diabetes experts now recommend keeping HbA1c around or below 7 percent for most patients, but not below 6.5 percent. Also, a higher HbA1c goal may be appropriate for certain patients, including those with a history of repeated episodes of low blood sugar, coronary heart disease, stroke or limited life expectancies.
Managing diabetes is complex because it requires care ful, sometimes daily attention to diet, monitoring blood sugars, and sometimes frequent adjustment of medication doses. It is also very important to get regular foot and eye exams, and, if necessary, treatment for high blood pressure and cholesterol — all of which are proven methods to reduce complications of diabetes.
A formal program or a conscientious primary care doctor can help you manage diabetes appropriately.
Consumer Reports. December 2012