Living With Diabetes Is Getting Easier--And a Cure Could Be on the Way
Mary Anna Pokerznik's life has changed twice because of islet cells, the tiny insulin factories found in the pancreas. The first time, she was 11 years old and was losing weight at an alarming rate. She was diagnosed with Type 1 diabetes, a disease in which the immune system attacks the islet cells, robbing the body of the insulin it needs to turn sugar into energy. She learned how to prick her finger for blood-sugar tests, inject herself with insulin twice a day, and eat carefully. "I didn't care for it much," says the 30-year-old science teacher, who lives in Edmonton, Alberta, Canada. "It was very confining." The second time was 14 months ago, when Pokerznik took part in an experiment at the University of Alberta in which researchers injected islets culled from donor pancreases into her liver. There, the cells began producing insulin and freed her from the burden of injections. For now, at least, her diabetes is cured. "It's very liberating," she says.
The trial, reported last week in the New England Journal of Medicine, showed similar results in six other patients. Experts call it the most exciting diabetes news in decades and a glimpse of the future of diabetes treatment. The therapy may not be widely available for years, however. Larger trials, to begin this fall, will try to replicate the results of the Canadian study. But life is already changing for the nearly 1 million Type 1 diabetics in the United States, as new forms of insulin and tools for testing blood sugar help make the disease significantly easier to manage. "We are on the cusp of some real advances," says Philip Levin, director of the Diabetes Center at Baltimore's Mercy Medical Center. "[They] could make life a lot easier for patients."
Balancing act. Most of the 16 million people with diabetes have Type 2, which usually develops in adulthood and often can be controlled with diet and exercise. But people with Type 1 diabetes, who are frequently diagnosed as children, walk a difficult line, injecting insulin and monitoring their food intake to maintain a steady blood-sugar level. If it drops too low, diabetics become disoriented and can even pass out. Blood sugar that rises too high over many years can cause kidney and heart problems, as well as blindness.
Striking a balance means checking blood-sugar levels four times daily, injecting precise amounts of insulin, and following a rigid meal schedule. It isn't easy, says Robert Sherwin of Yale University, president of the American Diabetes Association, "The most intelligent people I know have a great deal of difficulty." Pokerznik agrees. "I would eat the same food every day and do the same exact activity," she says--and yet her blood-sugar levels still bounced around erratically.
Cygnus Inc. of Redwood City, Calif., is hoping to introduce a device early next year that will allow patients to monitor their blood sugar more closely--and eliminate some finger sticks as well. The Gluco- Watch Biographer works by sending a small electrical current over the skin, which stimulates the secretion of a tiny amount of fluid. It checks glucose every 20 minutes and sounds an alarm if the level becomes dangerously low or high. Patients need to double-check with a finger stick test before they inject insulin. Still, says Dick Eastman, Cygnus's medical director, "It will help patients keep track of whether their insulin doses are on target."
The insulin side of the equation is improving as well. Most diabetics use two kinds: long-acting insulin to give a baseline blood level, and a short-acting form to give a boost at mealtimes. But long-acting insulin tends to peak after a few hours, requiring patients to eat in order to keep blood sugar from plummeting. Pager-shaped insulin pumps that infuse a steady trickle through a tube inserted into the skin make it easier to maintain a steady state. Lynn Statham, a 38-year-old California flight attendant, says that her pump helps her cope with flight delays and other schedule changes. "I tell it what dose to give me based on my activity and what I eat," she says. "That way I'm not bottoming out on the plane."
A new form of long-acting insulin set to be introduced in the fall by Aventis Pharmaceuticals in Parsippany, N.J., should also flatten the peaks, maintaining a steady level for 24 hours. And companies are testing inhaled forms of insulin that could one day eliminate injections completely while allowing patients to take insulin in frequent, small doses.
Impatient patients. Yet doctors say their phones are ringing off the hook from diabetics wanting islet-cell transplantation. "Patients have been waiting a long time for something like this," says Paul Robertson, scientific director and CEO of the Pacific Northwest Research Institute in Seattle.
Many hurdles remain. Like other transplant recipients, participants in the Alberta study have to take drugs that suppress their immune system so it won't reject the foreign cells. And donor islet cells are scarce. Each patient received cells from at least two pancreases--and just 3,000 are donated each year in the United States. "We simply need more islets," says Susan Bonner-Weir, a researcher at the Joslin Diabetes Center in Boston, who is trying to grow islet cells in the lab.
Pokerznik is thrilled with her new freedom but acknowledges that the therapy is still experimental. "For all I know, it will stop working tomorrow," she says. "Really, this is just the beginning."
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[Graphic labels:]
Pancreas; Islet; Liver; Pancreatic duct
This story appears in the August 7, 2000 print edition of U.S. News & World Report.