It's May, the month we honor mothers, and nature continues to come back to life. We hope that you gain information each month about the latest in diabetes research so that you can make informed decisions about your health and that of loved ones. Once again, we ask you to e-mail us if you have a subject that interests you and we'll put it on our list of topics to look for. This month we have 3 abstracts about type 1 diabetes and children including one on insulin pumps, one on screening, and one on cardiovascular disease. We report on hypoglycemia associated autonomic failure in type 2 diabetes, and finally we look at the association of taking glitazones and heart failure. Keep reading and we'll keep looking.
As we do each month we start with some headlines about diabetes for you. We have received many emails from readers about coffee drinking. The Archives of Internal Medicine 2002;162:657-662 has an article which found that drinking a cup of coffee a day did not significantly raise blood pressure, taking into account family history, weight, exercise, drinking and smoking. However, the authors do state that they thought those with hypertension should give up caffeinated beverages for a week or so to see if it helps their blood pressure. The Associated Press has reported that Australia and the US have joined forces in a multimillion dollar venture to develop a vaccine against juvenile diabetes. This will be funded by the Juvenile Diabetes Research Foundation and Australia's National Health and Medical Research Council. We'll keep you posted. Those of you who are regulars on this site know that we stress low fat eating. The Annals of Internal Medicine 2002;136:523-528 published an article that suggests that blood flow to the heart is hampered after high fat meals. Coronary microcirculation-the tiny vessels that provide blood to the heart muscle-was found to be impaired. While the researchers were not able to determine if the increase in triglyceride levels had anything to do with the decrease in the heart's blood flow reserve, they do say that the findings suggest that patients with heart disease should be advised about eating meals high in fat. Finally, we have written about the effects of dietary supplements on our bodies. Reuters has reported that LipoKinetix a supplement marketed by Syntrax for weight loss has been implicated in seven cases of hepatitis. A word to the wise.
Now for our abstracts. Diabetes 2002;51:493-498 has an article titled Children with type 1 diabetes at increased risk for subclinical atherosclerosis by Dr. O.T. Raitakare et al from Finland. The group found carotid intima-media thickness(IMT) is significantly increased in children with type 1 diabetes compared with healthy controls. They examined 50 children with type 1 diabetes and 35 healthy matched controls with high resolution ultrasound to measure IMT. In a subgroup of 42 children, the researchers measured the formation of conjugated dienes induced by copper to determine the susceptibility of LDL to oxidation. They found that the mean carotid IMT was increased in children with diabetes. Concentrations of total cholesterol and LDL cholesterol were similar in the two groups. However children with diabetes had increased LDL diene formation suggesting increased in-vitro LDL oxidizability. The researchers emphasize the importance of early detection and control of vascular risk in young people with diabetes.
There was a fascinating article in Diabetes Care 2002;25:505,623-625 about Multiple Autoantibody screening predicts type 1 diabetes among teenagers by W. Hagopian et al in Seattle. The researchers found that it is possible to predict type 1 diabetes in the general population through multiple autoantibody testing. This has been shown to be useful in assessing the risk for diabetes among first-degree relatives of people with type 1 diabetes, but the authors point out that 90% of newly diagnosed type 1 diabetics do not have a close family member with diabetes. The researchers screened a total of 4505 school children, of which 3000 were followed for 8 years. Six of those children developed diabetes within a median interval of 2.8 years. The researchers reported "multiple defined autoantibodies were established by age 14 and prospectively identified all children who developed type 1 diabetes.
Our last article concerning diabetes and children comes from the Journal of Pediatrics 2002;140:235-240 and is titled Pubertal status influences insulin pump dosing in diabetic children by S.E. Gitelman et al from San Francisco. The researchers found that pubertal status influences the total daily insulin dose needed when converting from multiple daily injections to continuous subcutaneous insulin infusion (CSII). They evaluated CSII dosing in 65 diabetic children who had previously received multiple daily injections to achieve metabolic control. They found that pubertal patients required 18% reduction in their daily insulin dose to achieve optimal control. Prepubertal patients, in contrast, required minimal change in their daily insulin dose. In both patient groups optimal control was achieved when basal insulin dose comprised 40% t o 45% of the total insulin dose. In prepubertal patients, the maximal basal rate appears to occur in the late evening hours as opposed to the dawn phenomenon typically described in adolescents and adults. In adults, it is suggested that the total insulin dose be decreased by 25%, with 50% of that be basal insulin. The current findings indicate that the CSII dosing guide lines do not necessary apply to children.
Diabetes 51(3):724-733,2002 has an article titled Hypoglycemia-associated autonomic failure in advanced type 2 diabetes by S. A. Segael et al. The researchers tested the hypotheses that the glucagon response to hypoglycemia is reduced in patients who are approaching the insulin-deficient end of the spectrum of type 2 diabetes and that recent antecedent hypoglycemia shifts the glycemic thresholds for autonomic (including adrenomedullary epinephrine) and symptomatic responses to hypoglycemia to lower plasma glucose concentrations in type 2 diabetes. The researchers concluded that because the glucagon response to falling plasma glucose concentrations is virtually absent and the glycemic thresholds for autonomic and symptomatic responses to hypoglycemia are shifted to lower plasma glucose concentrations by recent antecedent hypoglycemia, patients with advanced type 2 diabetes, like those with type 1 diabetes, are at risk for defective glucose counter regulation and hypoglycemia unawareness, the components of hypoglycemia-associated autonomic failure and the resultant vicious cycle of recurrent iatrogenuc hypoglycemia. This may explain why iatrogenic hypoglycemia becomes limiting to glycemic control as patients approach the insulin-deficient end of the spectrum of type 2 diabetes.
Glitazones associated with increased risk of heart failure, by Dr. T. Delea from Mass. was the topic of a talk at the American College of cardiology 51st Annual Scientific Session as reported by Reuters Health. He used a database that included claims from 35 health insurers. A review of claims filed from the period Jan. 1995 to March 2001 identified 8288 diabetics who were treated with troglitazone, rosiglitazone or pioglitazone, and 41,440 diabetic patients who did not use glitazones. Patients who were diagnosed with heart failure in the 12 months prior to the initial claim for a glitazone were excluded from the study. The initial claim for a glitazone served as the index date. During an average follow-up from the index date of 8.5 months, the risk for heart failure was 4.5% among the gllitazone users and 2.6% in nonusers. After adjusting for other potential confounders, the use of glitazones was associated with a relative hazard of 1.51 for heart failure.
Dr. John Buse, who heads a special committee on heart disease at the ADA, said glitazones are useful medications, but he cautioned that they need to be carefully monitored. He said most physicians are aware that the drugs are associated with both plasma volume expansion and edema. "The problem is that people who are already at high risk for heart failure," said Dr. Buse. Dr Delea agreed and noted that in his study, glitazone users tended to be older and also had multiple risk factors for heart disease. "But nonetheless there is a consistency of effect for glitazone," said Dr. Delea. "And the association between glitazone and heart failure is the same across all subgroups". This data is based on observational data and needs to be confirmed in a clinical trial.
BSP
