Consistent Directions of Effect for Established Type 2 Diabetes Risk Variants Across Populations

The Population Architecture using Genomics and Epidemiology (PAGE)

Diabetes.diabetesjournals.org: 4/3/2012.

Common genetic risk variants for type 2 diabetes (T2D) have primarily been identified in populations of European and Asian ancestry. We tested whether the direction of association with 20 T2D risk variants generalizes across six major racial/ethnic groups in the U.S. as part of the Population Architecture using Genomics and Epidemiology Consortium (16,235 diabetes case and 46,122 control subjects of European American, African American, Hispanic, East Asian, American Indian, and Native Hawaiian ancestry). The percentage of positive (odds ratio [OR] >1 for putative risk allele) associations ranged from 69% in American Indians to 100% in European Americans. Of the nine variants where we observed significant heterogeneity of effect by racial/ethnic group (P_{heterogeneity} < 0.05), eight were positively associated with risk (OR >1) in at least five groups. The marked directional consistency of association observed for most genetic variants across populations implies a shared functional common variant in each region. Fine-mapping of all loci will be required to reveal markers of risk that are important within and across populations. Read More

Linagliptin Found Effective, Safe in African Americans With Type 2 Diabetes

Cardiology News Digital Network: By: MIRIAM E. TUCKER, 5/25/2012.

PHILADELPHIA – Linagliptin was associated with significant improvements in hyperglycemia in a multicenter, randomized, placebo-controlled, double-blind trial of 226 African-American patients with type 2 diabetes.

“African Americans have a 77% greater likelihood of developing diabetes yet tend to be underrepresented in clinical trials of antidiabetic drugs,” said Dr. James R. Thrasher, director of medical investigation at Arkansas Diabetes and Endocrinology Center, Little Rock. “We wanted to look at this group with higher rates of diabetes and higher risk for complications of diabetes.” Read more

Emergence of a Predictive Clinical Biomarker for Diabetic Neuropathy

Diabetes.diabetesjournals.org: 5/24/2012.

Diabetes is often complicated by the development of neuropathy, with up to a third of the direct costs of diabetes attributed to neuropathy-related morbidity (1). The incidence of diabetic neuropathy increases with duration of diabetes, affecting up to 50% of diabetic patients after 25 years of disease (2). To date, the development of neuroprotective and disease-modifying approaches for diabetic neuropathy has been disappointing. Therapeutic approaches with aldose reductase inhibitors and nerve growth factors have so far proved unsuccessful (3). Despite the promise of positive outcomes in research animal models, clinical trials of neuroprotective therapies have failed to yield significant benefit. In part, this lack of success reflects the absence of sensitive and robust methods for early detection of neuropathy (4). It is perhaps not surprising that initiation of therapy when axonal degeneration is advanced—well after the horse has left the gate—has resulted in trials that have been negative to date. Read more

Through the Fog: Recent Clinical Trials to Preserve β-Cell Function in Type 1 Diabetes

diabetes.diabetesjournals.org: 5/24/2012.

Dawn portrays shadows and fleeting openings in the heavy fog. First awake, inquisitive eyes attempt to pierce the grayness, searching out a stepping stone secure enough to settle on next. “There it is, a beam showing a path.” Anxious dreams of the night begin to fade. He prepares to move forward, cautiously choosing the direction. Adjacent, others stir. Where is the path they saw so clearly only a short while before? Now, only nothingness surrounds them. The imperative that first drove them to start the journey appears less urgent. Stuck in place, feet encased in heavy mud, their despair spreads to others. “Surely this direction is wrong. There must be an easier path,” they cry. There is no end to be seen, and we have been traveling many, many years.

—A parable by Carla J. Greenbaum

For almost 50 years, type 1 diabetes has been described as an autoimmune disease characterized by the T-cell–mediated destruction of β-cells, which begins long before clinical diagnosis. Clinical trials accepting this premise and aimed at modulating the immune system before or after onset of clinical disease have failed to prevent or cure type 1 diabetes. Nonetheless, clinical trials have provided useful knowledge. Whereas some studies have demonstrated no effect on disease progression, a small number of therapies have transiently delayed the decline of β-cell function in recently diagnosed patients. Read more

A Systematic Review of Community-Based Participatory Research to Enhance Clinical Trials in Racial and Ethnic Minority Group

hsr.org: 5/24/2012.

Keywords: Community-based participatory research;clinical trials;systematic review;racial and ethnic minorities

Objective: To examine the effectiveness of current community-based participatory research (CBPR) clinical trials involving racial and ethnic minorities.

Data Sources: All published peer-reviewed CBPR intervention articles in PubMed and CINAHL databases from January 2003 to May 2010.

Study Design: We performed a systematic literature review.

Data Collection/Extraction Methods: Data were extracted on each study’s characteristics, community involvement in research, subject recruitment and retention, and intervention effects.

Principal Findings: We found 19 articles meeting inclusion criteria. Of these, 14 were published from 2007 to 2010. Articles described some measures of community participation in research with great variability. Although CBPR trials examined a wide range of behavioral and clinical outcomes, such trials had very high success rates in recruiting and retaining minority participants and achieving significant intervention effects. Read more

Heart disease and stroke deaths drop significantly for people with diabetes

Cdc.gov: May 22, 2012.

Death rates for people with diabetes dropped substantially from 1997 to 2006, especially deaths related to heart disease and stroke, according to researchers at the Centers for Disease Control and Prevention and the National Institutes of Health.

Deaths from all causes declined by 23 percent, and deaths related to heart disease and stroke dropped by 40 percent, according to the study published today in the journal Diabetes Care (http://care.diabetesjournals.org/content/35/6/1252.full).  Scientists evaluated 1997-2004 National Health Interview Survey data from nearly 250,000 adults who were linked to the National Death Index. Although adults with diabetes still are more likely to die younger than those who do not have the disease, the gap is narrowing.

Improved medical treatment for cardiovascular disease, better management of diabetes, and some healthy lifestyle changes contributed to the decline. People with diabetes were less likely to smoke and more likely to be physically active than in the past. Better control of high blood pressure and high cholesterol also may have contributed to improved health.  However, obesity levels among people with diabetes continued to increase. Read more

“Pre-diabetes,” diabetes rising among U.S. teens

Reuters.com: By Amy Norton NEW YORK | Mon May 21, 2012 5:49pm EDT.

(Reuters Health) – The percentage of U.S. teenagers with “pre-diabetes” or full-blown type 2 diabetes has more than doubled in recent years — though obesity and other heart risk factors have held steady, government researchers reported Monday.

The good news, the researchers say, is that teen obesity rates leveled off between 1999 and 2008 — hovering between 18 percent and 20 percent over the years.

Rates of high blood pressure and high LDL cholesterol (the “bad” kind) also remained steady.

But the picture was different with so-called pre-diabetes and with type 2 diabetes. Those conditions were seen in nine percent of teens in 1999-2000, but that figure rose to 23 percent in 2007-2008, the researchers report in the journal Pediatrics.

“That was unexpected, especially since obesity has been leveling off,” said lead researcher Ashleigh May, of the Centers for Disease Control and Prevention (CDC). Read More