Taking The Sting Out Of DiabetesCatherine Arnst
A diagnosis of diabetes raises a depressing vision of daily, painful insulin shots and a lifetime of complications. But there has been a sea change in the treatment of the disease over the past five years: New classes of drugs can eliminate the need for insulin injections in some patients, while easy-to-use home glucose monitoring equipment allows patients to precisely control their blood-sugar levels and stave off the dread effects of diabetes. In the pipeline are still more drugs, including a method for inhaling insulin that could eliminate needles forever.
The biggest change, perhaps, is that the ideal treatment is now patient-centered, rather than doctor-directed. Two large clinical studies in the last few years have proven that very tight control of blood sugar, or glucose, levels can make a huge difference in the progression of this chronic disease. Ideally, then, patients should tightly monitor their glucose levels throughout the day and take action whenever they are too high or low. And they can choose from more than 200 combinations of drugs to maintain control over their blood sugar.
OBESE CHILDREN. The downside, however, is that study after study has shown that few diabetics get optimal care. "Today, at least theoretically, everybody in the U.S. can have excellent blood-sugar control," says Dr. John Buse, director of the Diabetes Care Center at the University of North Carolina at Chapel Hill School of Medicine. But many physicians are still unaware of the new treatments that make that goal attainable. "The message is shifting down, but it's not 100%," says Buse.
Even more worrisome, many diabetics don't even get treatment until the disease is well-advanced. The American Diabetes Assn. estimates that at least one-third of people with diabetes go undiagnosed until they develop complications. And those complications can be horrific. Diabetes is the leading cause of both blindness and kidney failure. Diabetics are two to four times more likely to suffer from heart disease and stroke than the general population, and nerve damage in lower limbs leads to 56,000 amputations a year.
More and more people are at risk of such fates. Over 16 million Americans suffer from diabetes, almost 7% of the population. The reason is easy to pinpoint--more than 90% of diabetics are overweight at the time of diagnosis. Obesity is the single largest risk factor for diabetes, and both conditions are rising dramatically, across every income level and every age group.
Most heartbreaking is the jump in diabetes in children as young as 10. Once again, say doctors, the main reason is a corresponding rise in obesity. Children had long been thought to be susceptible only to a version of the disease called Type 1, a lifelong autoimmune disorder that afflicts less than one million people in the U.S. Type 2, a different disease that accounts for more than 90% of all cases, was once called adult-onset diabetes because it was typically found in people over the age of 45. But in the 1990s, pediatric centers began to discover Type 2 in children. Now, the ADA reports that as many as 45% of children with newly diagnosed diabetes have Type 2.
Both types of diabetes result from the body's inability to properly metabolize insulin, the hormone that enables glucose, or sugar, to enter and fuel the cells. In Type 1, which is usually genetic, a haywire immune system destroys the insulin-producing cells in the pancreas. With Type 2 diabetes, the body is still producing insulin, but the cells become resistant and stop absorbing the sugar they need to live. In both cases, the sugar builds up to poisonous levels in the bloodstream until it destroys organs.
The goal, then, is to bring blood sugar down to normal levels, usually with drugs--although a well-balanced diet and exercise can do the trick in mild cases. For decades, the only other choices were daily insulin injections, sometimes combined with sulfonylureas, which help the body absorb the insulin. There have been five new classes of drugs in the past five years, however, and all can be taken orally. Now, the ADA recommends that patients be treated with a combination of drugs, which are tailored to their condition.
NO NEEDLES. In the early stages of the disease, for example, some patients may be able to maintain their blood sugar levels with metformin, which encourages the liver to prevent excessive release of sugar into the blood. Other new treatments include alpha-glucosidase inhibitors, which inhibit the delivery of sugars from the intestines to the bloodstream, and megitinides, fast-acting sulfonylurea-like compounds that stimulate the production of natural insulin.
Not all of the new drugs have been successful. One of the most promising was thought to be Rezulin, in a category called thiazolidinediones. These drugs allow insulin to be used more efficiently by the body, cutting down on the need for insulin injections. Rezulin was pulled from the market last year because of deadly liver complications in some patients. But a similar drug, Avandia, was approved in 1999, and studies have found it to have a safer profile.
There are more drugs in the pipeline, including compounds that directly affect the pancreatic cells known as beta cells that produce insulin. But diabetics may be most encouraged by a new technology that could eliminate needles altogether. Inhale Therapeutics Systems and Pfizer are together developing a device that allows patients to inhale a powdered form of insulin. In a large clinical study just reported in Lancet, a British medical journal, patients using the device were able to control their blood sugar level as well as those using injections of insulin. The companies are expected to seek approval for the device from the U.S. Food & Drug Administration within a year or two.
Patients, meanwhile, are being encouraged to take a more active role than ever in the management of their disease. Glucose monitoring kits that can be used at home allow patients to check their blood sugar levels throughout the day and take the necessary medications as soon as they are required. Implantable monitoring devices, which would automatically alert the patient to changes in blood sugar levels, are under development.
Patients should also be aware that within five to 10 years of diagnosis their bodies will progressively lose the ability to make insulin, no matter how closely they monitor their condition. That means treatment plans must be readjusted. Hopefully, with constant vigilance, that is the worst that will happen.