Mariana Londoño and her mini-computer go everywhere together: to school, home, out with friends, to the movies or to dinner. They even sleep together. And no, it’s not a tablet, videogame console or a music device. The 18-year-old student travels permanently with an insulin dispenser pump connected to her body that helps control her Type 1 diabetes.
“It doesn’t bother me at all; I take it to parties and everywhere. Nothing can keep me from living my life,” Londoño says. “When I don’t have it I feel differently, as if something is missing. The pump is already part of me.”
The insulin dispenser pump, which continuously monitors glucose levels, is part of the technological developments that help more than 23 million U.S. diabetes patients. Rigorous control of glucose is directly linked to the patient’s long-term life expectancy and diminishes the deterioration of the nervous system, the kidneys, the eyes, and the cardiac complications associated with the disease.
“Insulin was discovered in 1920 and before then diabetes was a lethal disease,” says Dr. Alejandro Díaz, an endocrinologist specializing in pediatrics at Miami Children’s Hospital.
But the handling of the disease changed significantly after the study “Diabetes Control and Complications Trial” was published in 1994. The study demonstrated that strict monitoring of glucose levels in the blood reduces the risk of eyesight disorders by 76 percent, kidney disorders by 50 percent and nervous system disorders by 60 percent.
“With these results we realized that we had to be much more aggressive in treating diabetes and we began to use methods of daily multiple-dose injections, because we know that an intensive control reduces complications significantly,” Díaz says.
The insulin dispenser pump incorporates developments of the last 30 years. The pump, a mini computer, connects to the patient’s body through a catheter, usually placed in the abdominal area, which has the dual task of constantly providing “basal” insulin and extra doses — called “boluses” — to process meals.
“The pancreas produces 40 percent of the insulin in basal form that is always present so that cells can consume glucose. The other 60 percent is produced when we eat, particularly carbohydrates,” says Díaz.
While the pump and insulin injections are similar, the pump has its advantages.
“With the insulin pump I can provide even smaller or more precise amounts than with the syringe,” Díaz says.
This is particularly important for small children, for whom injected doses can be very high. The pump runs continuously, avoiding the swings of blood sugar levels in the early morning or throughout the night.
The possibility of programming the insulin doses in accordance with the patient’s daily routine also allows the doctor to prescribe different amounts of basal insulin, depending on physical activity.
“For instance, if the patient is a boy who plays a lot at school between 1 and 3 in the afternoon, his sugar can be lowered by giving him the same dose as when he is resting,” Díaz says. “With the pump I can lower the dose specifically during those hours, something I can’t do with syringes.”
From the patient’s perspective, the pump also spares them the need to be injected several times a day, since the device supplies the doses through a catheter that is changed every two or three days.
“Life has turned a lot easier because I don’t have to inject myself with insulin; all I have to do is press buttons,” Londoño says. “There is not as much pain because the pump is already connected to my body.”
Díaz considers the insulin pump “recommendable for all patients, regardless of their age,” because of its benefits. However, he acknowledges that the price can be a problem. The device cost $3,000 to $6,000 and, though many insurance companies cover it at least partially, the patient always has to pay a portion.
Technological advances also help control sugar content. Monitors continuously measure glucose levels and offer automatic measurements every five or 10 minutes. They differ from other portable monitors in that the sensor is in the patient’s body and transmits the collected information to a receptor that stores it. This allows the patient and his medical team to follow the fluctuations of sugar levels in real time.
Doctors believe that in the future, insulin pumps and continuous glucose monitors will function in a coordinated fashion, as with a “bionic pancreas,” in which the insulin doses would be programmed automatically based in measurements performed every minute. In fact, Díaz says that “in Europe there is already a pump of combined sensors that turns itself off if glucose drops lower than a certain level.” This technology has not yet been approved for use in the United States.
Recent developments in controlling sugar levels in the body are now better understood. Dr. Paul Jellinger, endocrinologist of Broward Regional Memorial Hospital and professor of Chronic Medicine at the University of Miami Miller School of Medicine, explains that “for decades we have thought that diabetes control was all about insulin, either supplying it or making the pancreas produce more or making that which is already produced to function better. Yet in the last eight or nine years we have come to realize that the story does not end with insulin and that there are other hormones that play key roles in controlling sugar.”
Recent studies have shown that incretins, a group of hormones secreted throughout the small intestine, play a key role in controlling glucose. They are activated when the individual consumes carbohydrates, stimulating the production of insulin in the pancreas and blocking the production of another hormone, glucagon, which provokes high levels of sugar in the blood.
“Patients with diabetes have high levels of sugar not only due to an insulin deficit but also due to an excess of glucagon,” says Jellinger, adding that incretins go to the core of this problem. Furthermore, incretins have the big advantage of working with sugar levels in the blood. They stop acting after levels reach a normal point, as opposed to other medicines that stimulate insulin production and can generate big swings in glucose levels.
Therapies for diabetes based on incretins seek to elevate GLP-1. This can be done in two ways: through a pill that blocks the hormone absorption, thus promoting insulin production and diminishing glucagon, or through injections of a drug similar to that of GLP-1 but with a delayed effect that allows it to remain in the body longer. The injectable therapy allows larger doses and promotes a sensation of fullness in the stomach, which promotes weight loss in patients.
This type of treatment is only effective in patients with Type 2 diabetes, who produce low levels of insulin. It’s not effective in Type 1 diabetes, in which the pancreas does not produce insulin.
“They are very smart drugs that do what they have to do but then stop,” says Jellinger, who adds that “most of the patients who have tried one of the two forms of therapy based on incretins are happy with the results. The control of diabetes is very effective because they lower the sugar without reaching levels that may be too low.”
“The full story concerning diabetes is not all about insulin. GLP-1 is playing an increasingly important role in this new narrative,” he adds.