Hypertriglyceridemia associated with high levels of retinal binding protein 4 (RBP4) in individuals with Type 2 diabetes is enhanced in the presence of a variant of the apolipoprotein A5 gene (APOA5), report researchers.

Patients with Type 2 diabetes have an increased prevalence of hypertriglyceridemia compared with nondiabetics, say researchers Luis Masana and colleagues from the Sant Joan University Hospital, in Reus, Spain.

Previous research has shown RBP4 to be “associated with insulin resistance and hypertriglyceridemia in obesity, the metabolic syndrome, and Type 2 diabetes,” say the investigators.

As APOA5 has been suggested to be a “genetic modulator” of triglycerides, the team assessed the relationship between RBP4 concentration, triglyceride levels, and genotype of the APOA5 variant -1131 T/C in 165 Type 2 diabetic patients.

The researchers found that levels of RBP4 were significantly correlated with triglyceride levels and all the components of triglyceride rich lipoproteins in the participants.

No direct link was found between APOA5 -1131 T/C genotype and RBP4 levels. However, carriers of the C allele of -1131 T/C had significantly higher triglyceride levels in the presence of elevated RBP4 levels (at or above the gender-adjusted mean of 43.20 mg/l for men and 37.65 mg/l for women) than TT homozygotes.

More specifically, high RBP4 levels plus presence of the C allele of -1131 T/C increased the risk for hypertriglyceridemia (above 1.69 mmol/l; 149.68 mg/dl) 7.46??”fold.

“The increased RBP4 levels could be considered a consequence of an acquired metabolic disorder acting on lipid- and glucose-metabolic pathways,” suggest the authors. “The presence of the genetic background of the APOA5 -1131 T/C genetic variant would then increase the metabolic actions of RBP4.”

They conclude: “Based on these data, the combination of high RBP4 levels in diabetic patients carrying the unfavorable APOA5 genotype will increase their chances of developing hypertriglyceridemia.”

The results of this study are published in the journal Nutrition, Metabolism and Cardiovascular Diseases.

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd; 2009

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Revisiting a cohort from a national Filipino study population after 9 years reveals rapidly rising levels of Type 2 diabetes, researchers report.

Type 2 diabetes is a growing epidemic in the Philippines, but there are no existing data on the incidence of this disease in the region.

In 2007, Maria Luz Soria (University of the Philippines, Manila) and co-workers followed-up individuals from six of 13 regions of the country (47% of the national study population) who participated in the 1998 Food and Nutrition Research Institute 5th National Nutrition Survey to determine the 9-year incidence of Type 2 diabetes, impaired fasting glucose (IFG), and impaired glucose tolerance (IGT).

The cohort consisted of 1749 respondents out of the previous 2122 participants from the 1998 study. Of these, 1386 consented to a fasting blood glucose (FBG) test using whole blood capillary samples, and 1275 completed a 2-hour post-glucose load determination.

Type 2 diabetes was defined according to 1999 World Health Organization criteria using whole blood capillary glucose as levels of at least 110 mg/dl based on FBG, and as levels of at least 200 mg/dl based on 2-hour post-glucose load.

Comparing the 1998 and 2007 data, the authors noted a significant increase in FBG from 91.5 mg/dl to 103.3 mg/dl, and a 3-cm increase in waist circumference.

Fasting and post-load glucose levels identify patients with prediabetes using different criteria. Of the 1275 respondents who consented to both measures of glucose abnormality, the prevalence of pre-diabetes was 31.3%. When FBG alone was used, the authors detected 17.5% with pre-diabetes.

An additional 13.8% were detected if 2-hour post-glucose load was included in the diabetes screening, leading the authors to recommend the use of this measure in addition to FBG in population-based surveys, community screening programs, and clinical practice.

The 9-year incidence of Type 2 diabetes was 16.3%. Prevalence rates for Type 2 diabetes, IFG, and IGT were 28.0%, 17.5%, and 23.9%, respectively, although the authors acknowledge that comparing data from two points in time, instead of continuous follow-up of the cohort throughout the 9 years, may lead to overestimates of morbidity.

“We observed an alarming growth of diabetes, IFG, and IGT in a relatively short interval that warrants early aggressive intervention for prevention and management,” conclude the authors in the journal Diabetes Research and Clinical Practice.

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd; 2009

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Results from a randomized trial of the bile acid sequestrant colestilan show that it is effective for improving glycated hemoglobin (HbA1c) and reducing low-density lipoprotein (LDL) cholesterol in Type 2 diabetics.

“Diabetes and frequently complicating hypercholesterolemia are known independent risk factors for onset and progression of cardiovascular and cerebrovascular events,” say Kazuoki Kondo (Mitsubishi Tanabe Pharma Corporation, Tokyo, Japan) and co-workers.

In this study, the team recruited 183 patients with Type 2 diabetes with a fasting plasma glucose of 7.2??”11.1 mmol/l and an HbA1c of 7.0% or more. They were randomly assigned to receive either colestilan 4.5 g/day or placebo for 12 weeks.

Writing in the journal Diabetes, Obesity and Metabolism, the team report that at 12 weeks, colestilan had significantly reduced both HbA1c and fasting plasma glucose by 0.9% and 1.2 mmol/l, respectively, but no significant reductions in fasting insulin were observed.

A significant 22.5% reduction in LDL cholesterol was also achieved by the treatment group versus placebo at 12 weeks.

The most frequently observed adverse events were constipation, nasopharyngitis, and eczema, which occurred in 13.0%, 19.6%, and 5.4% of the colestilan-treated patients, respectively, versus a corresponding 4.4%, 13.2%, and 0.0% of the placebo-treated group. No cases of hypoglycemia or death occurred during the study.

“Colestilan when given alone alleviates markers of hyperglycemia and dyslipidemia in patients with Type 2 diabetes,” summarize the authors.

“This drug might therefore be expected to exert diverse beneficial effects in a wide range of patients with multiple cardiovascular risk factors,” they add.

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd; 2009

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