Diabetes News for April 28, 2002
Diabetes May Interfere With Heart's Clock
It is well-established that diabetes is a risk factor for heart disease, but the mechanisms are not clearly understood. One new study presents a possible explanation for this link.
The study was conducted by researchers at the University of Texas-Houston Medical School, who presented their findings at the annual Experimental Biology 2002 conference held in New Orleans (April 22, 2002). The researchers based their study on the idea that the heart has a molecular clock that keeps track of the time of day. This clock allows the heart to slow down when a person sleeps, and speed up when a person awakens.
The researchers used rats who had been bred to develop diabetes to study how the disease affects the heart's clock. They found that the hearts of the rats with diabetes were about three hours behind those of the rats without diabetes. The researchers postulate that the hearts of the rats with diabetes prepare for awakening three hours too soon, and then aren't prepared for the actual awakening three hours later. The researchers believe that this might explain the prevalence of early-morning heart attacks in humans.
More research is needed to determine whether diabetes interferes with the body's natural clock in humans, and whether this represents a significant health risk.
  
Blood Clotting Possible With Immune Treatment
According to documents posted on their website, the US Food and Drug Administration (FDA) warns that intravenous immune globulin (IGIV) may lead to dangerous blood clots, which can create problems such as chest pain, heart attacks, and congestive heart failure.
IGIV consists of antibodies from human plasma that are stabilized with sugars or proteins like glucose, sucrose, or albumin. It is used as a treatment for people with a weakened immune system, such as those with HIV bone marrow transplant or certain kinds of leukemia. Doctors are not sure why IGIV may lead to clotting, but say that rapid infusions of it may be a possible risk factor.
The FDA encourages anyone who is involved in administering IGIV to people to read the package inserts carefully. People with extra risk factors for clotting, such as diabetes, coronary artery disease, hypertension, and cerebrovascular disease, should be carefully monitored.
Fight Type 2 Diabetes With Fish?
For people at risk for Type 2 diabetes, particularly people who are overweight, doctors usually recommend a change in diet to decrease their risk. These changes include cutting back on high-fat, high-sugar foods. A small, new study shows that doctors may also recommend that people consume more fish in order to increase their insulin sensitivity.
Recently, researchers from Pennington Biomedical Research Institute at the Louisiana State University in Baton Rouge conducted a study of twelve overweight men and women with insulin resistance who were between the ages of 40 and 70. All of the participants consumed 1.8 grams of docosahexaenoic acid (DHA) at breakfast during the study. DHA is an omega-3 fatty acid found in fish oil.
After twelve weeks, the researchers compared the participants' blood levels of insulin to the levels that they'd had at the beginning of the study. They found that 70% of the participants had an improvement in their insulin function, and this change was clinically significant in 50% of the participants.
The researchers presented their findings at the annual Experimental Biology 2002 conference in New Orleans (April 22, 2002), but they stressed that more research is needed to confirm the benefits of DHA for people with diabetes. They encourage people with diabetes to consult their doctors before making any major dietary changes, especially because DHA has a slight blood-thinning property.
Poor Control May Create Indigestion
It is not uncommon for people with diabetes to have gastrointestinal problems like heartburn and stomach pain. Recently, researchers set out to determine the cause of these problems.
Over 1,100 people with diabetes participated in a study conducted by researchers at the University of Sydney, Australia. The participants were surveyed about their gastrointestinal problems, and 463 were tested to determine their blood sugar control. Like other diabetes complications, researches found that poor blood sugar control was also strongly connected with digestive problems.
The researchers also found that other complications, like kidney and retina damage, were linked as well with digestive problems. The number of complications with diabetes that people reported directly corresponded to the number of digestive problems they had. These problems included gastroesophageal reflux (heartburn), abdominal pain, and constipation.
The study is published in the American Journal of Gastroenterology (volume 97, pages 604-611, March 2002), and its authors hypothesize that digestive problems are likely caused by damage to nerves that control the function of internal organs. They stress the importance of good control of blood sugar levels.
Gestational Diabetes And Chromosome Defects
Gestational diabetes is a form of diabetes that develops during pregnancy, and usually goes away after the woman gives birth. New research shows that the condition may signal preexisting conditions that could result in chromosomal abnormalities in the women's children.
The study has been published in the American Journal of Epidemiology (volume 155; pages 719-724; April 15, 2002). Researchers at the Boston University School of Medicine in Massachusetts examined the health records of over 7,300 pregnant women who had had an amniocentesis to detect chromosomal abnormalities. The women had participated in a study in the 1980s, and were followed for one year after giving birth.
The researchers found that the women who developed gestational diabetes were twice as likely to have children with chromosomal defects than women who did not have the condition. This risk was associated with defects in sex chromosomes, in which the children had an extra X chromosome. Although both boys and girls can have an extra X chromosome without apparent problems, boys may develop Klinefelter's syndrome, in which they have small testicles and later infertility.
Study authors believe that some women develop gestational diabetes because they already have underlying biochemical abnormalities that may result in chromosome defects. In addition, women with gestational diabetes may have an increased risk of developing Type 1 or Type 2 diabetes. They believe that more research is needed into the subject of gestational diabetes.
Cholesterol Screening Lower In Some Groups
Although elevated cholesterol is a major risk factor for heart disease, a recent survey indicates that not all ethnic groups receive cholesterol screenings and appropriate treatment for high cholesterol.
Statistics were released by the Veteran's Administration Puget Sound Health Care System in Seattle, Washington, indicate that 63% of adults get their cholesterol levels checked at least once, but that only 37% of Latinos and 50% of African Americans had had a screening. Sixty-six percent of whites stated that they'd had a cholesterol screening.
In addition, they found that 50% of whites who were prescribed a medication to control their cholesterol level actually took their medication, while only 28% of Latinos and 29% of African Americans did so. Those who had heart disease and diabetes were more likely to take the cholesterol medication.
The researchers are not sure why there are differences in screening rates and medication use along ethnic lines, but believe that they might be due to unmeasured factors, such as economic differences, patient preferences, or physicians' understanding of appropriateness of cholesterol screening. The results of the survey have been published in the Archives of Internal Medicine (volume 162; pages 929-935; April 22, 2002).
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