After our monthly headlines we will bring you articles on the accuracy of the Gluco watch and the continuous glucose monitoring system during hypoglycemia, diabetes and an increased risk of liver disease, body iron stores in relation to risk of type 2 diabetes, antioxidants and diabetes, and metabolic control in adolescent girls.
Let's begin with our headlines this month which run the gamut of topics. Diabetes Care, Feb, 2004 has an article by Dr. Stephen M.Willi et al from the University of South Carolina which addresses a very low calorie diet to control teens' diabetes. They evaluated 20 obese teens and put them on a very low-calorie diet. The diet consisted of about 100 grams of protein and less than 30 grams each of fat and carbohydrates per day which delivered between 680 and 800 calories. This translates to 13 ounces of lean meat and 3 cups of vegetables along with 8 cups of fluid and supplemental salt daily. The mean blood glucose levels fell from 162 to 100 mg/dl, After 60 days the average weight loss was 25 pounds and remained reduced two years later. All but one was able to discontinue a diabetic therapy.
The April issue of The American Journal of Physiology-Endocrinology and Metabolism had an article written by Dr. Marc Hammerman from Washington University in which he describes the transplantation of embryonic pig insulin cells into diabetic rats. The rats, even without drugs to prevent immune rejection, adopted the pig cells as their own and produced their own insulin. "Before, all pig cells when put into another specie's tissue were robustly rejected by the immune system. In this model, using developing pig pancreas, it appears we can overcome this" said Dr. Marc Hurlbert associate director at the JDF.
Diabetes, Feb., 2004 has an article by Dr. Peter Okin et al of Cornell Medical Center which examines ECG signs identify which identify diabetics with high death risk. A computerized electrocardiogram or ECG can show which people with type 2 diabetes have a particularly high risk of dying. The researchers examined ECGs that were associated with mortality risk in the general population to see if they could be of use with diabetics. After taking into account age and other factors, two features on the ECG were significant predictors of death. One, known as ST segment depression, conferred a three-fold high risk of cardiovascular mortality. Both ST segment depression and another ECG feature, called the QT interval, doubled the risk of all-cause mortality.
The same risk factors that lead to heart attack and stroke: high blood pressure, smoking, obesity, diabetes and high cholesterol, can also cause kidney failure. This is the latest finding from the Framingham Heart Study says Dr. Caroline S. Fox in JAMA, Feb.18th issue. "This study re-emphasizes the importance of controlling the traditional risk factors in order to prevent not only heart attacks but also the development of kidney disease, stroke, and heart failure. We need to redouble our efforts to control blood pressure and reduce smoking so that kidney disease dos not have a chance to develop" said Dr. Robert A Phillips, Chairman of Medicine at Lenox Hill Hospital.
Feb.26, 2004 New England Journal of Medicine has an article of interest by Dr. Harshpal Sinngh Sachdev from India which assesses glucose tolerance in 1492 young adults from India who had height and weight measurements taken at regular intervals throughout childhood and adolescence to calculate BMI. A BMI over 26 was considered overweight. Nearly 11 percent of subjects had impaired glucose tolerance and 4.4 percent had diabetes. This later group typically had a low BMI between birth and 2 years of age, an increase in BMI that began at a young age, and an accelerated BMI into adulthood. Findings suggest that children destined to develop diabetes and glucose intolerance start life thinner than normal only to experience rapid increase in their body weight later in childhood and adolescence.
Researchers at the University of Colorado Health Sciences Center wrote up their research on an implanted continuous glucose monitor which they say cut the incidence of hypoglycemia down 47% and the incidence of hyperglycemia by 25%. The article is available in the March 2004 issue of Diabetes Care. The sensor, made by DexCom Inc. of San Diego California is about the size of and shape of a AA battery. It was implanted for 6 months in 15 adult type 1 diabetes patients who then wore a pager-sized wireless receiver.
Now on to those abstracts. Whenever we see articles of merit about glucose monitoring we share it with you as we receive many e-mails about the subjects. Diabetes Care 27:27-722-726, 2004 has an article titles Accuracy of the Glico Watch G2 Biographer and the Continuous Glucose Monitoring System during hypoglycemia written by the Diabetes Research in Children Network Study Group. The goal of this study was to assess the accuracy of these two systems (GW2B and CGMS) during hypoglycemia in children and adolescents with diabetes. Ninety-one children and adolescents with type 1 diabetes aged 3.5-17.7 years old wore one or two CGMSs, and 89 of those subjects wore one or two GW2Bs. Frequent serum glucose determinations were made during the day, overnight, and during insulin-induced hypoglycemia resulting in 192 GW2B reference pairs and 401 CGMS reference pairs during hypoglycemia. During hypoglycemia the median difference between the GW2B reference glucose pairs was 26mg/dl and between the CGMS reference glucose pairs was 19mg/dl. Sensitivity to detect hypoglycemia when the GW2B alarm level was set to 60mg/dl was 23% with a false-alarm rate of 51%. Analysis suggested that modified CGMS sensors became available in November 2002 might be more accurate than the original CGMS sensors. The report concludes the GW2B and the CGMS do not reliably detect hypoglycemia. Both of these devices perform better at higher glucose levels, suggesting they may be more useful in reducing HbA1c levels than in detecting hypoglycemia.
Gastroenterology, Vol126, No 2:460-468 has an article titles Diabetes raises the risk of serious liver problems by Dr. Hashem B. El-Serag from Houston. Men with diabetes have a 2-fold greater risk of developing liver cancer and other chronic liver diseases compared with nondiabetic men. The same may hold true in women, but the study did not have enough women to reach this conclusion. "Our study provides evidence that diabetes is an important risk factor for chronic liver disease including liver cancer," stated the author. The study is also the first to show that diabetes precedes, rather than follows, the development of these diseases. Using computerized records the Department of Veterans Affairs investigators studied all patients with a hospital diagnosis of diabetes between 1985 and 1990. They matched each diabetic patient with three nondiabetic patients and tracked them thorough 2000. Nearly all were men and had type 2 diabetes. None had liver disease when first diagnosed with diabetes. The increased risk "seems to be independent of age, gender, ethnicity, or (other) illness, and is higher in patients with diabetes for 10 years or more. In light of this study and earlier studies the researchers recommend that regular liver blood tests be done in people with diabetes.
JAMA 2004;291:711-717 has an article titled Body iron stores in relation to risk of type 2 diabetes in apparently healthy women by Rui Jiang, MD, DrPH et all -Type 2 diabetes is a common manifestation of hemochromatosis, a disease of iron overload. However it is not clear whether higher iron stores predict the development of type 2 diabetes in a healthy population. The researchers examined plasma ferritin concentration and the ratio of the concentrations of transferring receptors to ferritin in relation to type 2 diabetes. This was a prospective nested case-control study within the Nurses' Health Study cohort. Of the 32,826 women who provided blood samples during 1989-1990 and were free of diagnosed diabetes, cardiovascular disease, and cancer, 698 developed diabetes during 10 years follow-up. The controls (n=716) were matched to cases on age, race, and fasting status: and on body mass index (BMI) for cases in the top BMI decile.
Among cases the mean concentration of ferritin was significantly higher for controls. The researchers found higher iron stores (reflected by an elevated ferritin concentration and a lower ratio of transferring receptors to ferritin are associated with an increased risk of type 2 diabetes in healthy people independent of known diabetes risk factors.
Diabetes Care 2004. 27:362-366 has an article titled Antioxidants appear to protect against diabetes by Jukka Montonen et al of the National Public Health Institute in Helsinki. Eating a diet rich in antioxidants such as vitamin E appears to ward off diabetes. These are also available in whole grains and fruits and vegetables-important ingredients for an overall healthy diet. Losing weight and staying physically fit are two other important steps people should take to ward off type 2 diabetes. Previous research has shown that vitamin E and other antioxidants may protect people from type 2 diabetes by mopping up free radicals, cell-damaging particles that are a byproduct of normal metabolism. During the current study, the researchers followed more than 4,000 people between the ages of 40 to 69 for 23 years, noting what they ate and who developed type 2 diabetes. The researchers linked type 2 diabetes risk to a number of different forms of vitamin E, carotenoids and vitamin C. During the study follow-up, 164 men and 219 women developed type 2 diabetes. Although overall intake of vitamin E and carotenoids appeared to reduce the risk of diabetes, certain forms of those antioxidants showed more of an inhibiting effect than others. The researcher added that the complex nature of our diets makes it difficult to pinpoint whether a single antioxidant can truly reduce the risk of diabetes, perhaps explaining why vitamin C appeared to offer no protection from the condition. Since we eat meals with different foods and nutriments, the effect may conceal the effect of a single nutrient. They concluded that people who ate an antioxidant-rich diet have a healthier diet overall, making it hard to determine whether the protective effect came from antioxidants themselves. The researchers noted that people who are trying to reduce their risk of diabetes should stick to fruits, vegetables and other antioxidant-rich foods, rather than vitamin supplements.
Finally, we end with an article from Diabetes Care 27:707-715, 2004 titled Metabolic control in adolescent girls By Sherry Maharaj, PHD, CPSYCH et al from Toronto. This study investigated whether intimacy and autonomy in mother-daughter interactions and relational aspects of the self are associated with metabolic control in adolescent girls with type 1 diabetes. This was a cross-sectional study of 88 girls with diabetes with a mean age of 14.9 years, mean diabetes duration of 7.1 years and HbA1c of 8.9. The teens completed a self-report measure assessing self-concept. Mothers and daughters engaged in a 7 minute videotaped, problem-solving task involving a diabetes-related conflict issue. Interactions were rated using a macroanalytic rating system to assess intimacy and autonomy in parent-teen relationships. Metabolic control was measured by HbA1c. Self-concept in domains of perceived behavioral conduct, social acceptance, romantic appeal, and close friendships independently predicted HbA1c levels, together accounting for 30% of the variance. Also, the experience of emotional closeness rather than separateness in mother-daughter relationships was associated with lower HbA1c.
They concluded that relational aspects of the self and the experience of emotional closeness in relationships are associated with metabolic control in adolescent girls. Efforts to improve metabolic control in girls should include enhancing the self-concept and experience of relatedness in familial, peer, and patients-caregiver relationship.
BSP
