Diabetes Core Update – July 10, 2013

Overview

This episode of Diabetes Core Update delivers concise, clinically relevant summaries and discussions of recent research articles from the American Diabetes Association’s four journals. Hosted by Dr. Neil Skolnik and Dr. John Russell, the July 2013 episode covers important topics including the optimal measurement of waist circumference for assessing central obesity, the relationship between diabetes and cognitive decline, the links between diabetes duration and cancer risk, the role of adiponectin in metabolic syndrome, and mercury exposure’s association with diabetes incidence.

Key Discussion Points & Insights

1. Measurement of Waist Circumference: Mid-Abdominal vs. Iliac Crest

— Article from June 2013 Diabetes Care
(00:56 – 03:54)

• Background:
  Central obesity links strongly to cardiovascular risk and metabolic syndrome. Waist circumference is a preferred marker, possibly superior to BMI, but standardized measuring points differ:

  • WHO: midway between lowest rib and iliac crest.
  • ATP3 (NCEP): superior border of the iliac crest.

• Study Design & Findings:

  • Over 1,800 non-diabetic participants from the Taiwan Lifestyle Study were followed for a median of 31 months.
  • Both mid-abdominal and iliac crest measurements correlated notably with BMI and fat area.
    • “Mid waist circumference was better correlated to visceral fat area than was iliac crest measurements, particularly in women.” (B, 02:19)
    • Stronger association with hypertension, diabetes, metabolic syndrome, and relevant labs for mid-abdominal measurement.

• Clinical Perspective:

  • “Using our own natural landmarks on our body makes it much easier to have consistent measurement… I think if you thought office to office… you’re going to have more variation.” (C, 04:34)
  • While bony landmarks are easier to standardize, evidence suggests the mid-abdominal measure more closely reflects disease risk.

2. Type 2 Diabetes and 12-Year Cognitive Decline

— Article from June 2013 Diabetes Care
(03:54 – 07:09)

• Study Summary:

  • ~1,300 individuals >40 years, Netherlands, tracked cognitive function at baseline, 6, and 12 years.
  • Participants with diabetes at baseline showed substantially greater decline in:
    • Information processing speed
    • Executive function
    • Word recall

• Notable Findings:

  • Incident diabetes led to modest early declines, notably in information processing speed.
  • “A three times larger decline in information processing speed, and a four times larger decline in executive function among patients with diabetes at baseline is impressive and scary.” (B, 07:09)

• Clinical Significance:

  • Diabetes now firmly associated with cognitive decline—possibly through microvascular effects even absent overt stroke.
  • Reinforces aggressive management of overall risk: “Another reason to try to address as aggressively as possible and reasonable the different risk factors; blood glucose, hypertension, and cholesterol.” (B, 08:28)

3. Diabetes Duration, Insulin Use, and Cancer Prevalence

— Article from June 2013 Diabetes Care, BRFSS data
(07:09 – 10:25)

• Study Summary:

  • Data from over 25,000 adults diagnosed with diabetes.
  • Longer diabetes duration → higher cancer prevalence (P <0.0001, linear trend).
    • Men/women with diabetes >15 years: 60–80% higher cancer rates compared to <15 years.
    • Insulin users: 30% higher cancer prevalence than non-users.

• Analysis & Reflections:

  • Links with overweight status and certain cancers (breast, colon, prostate). “...those cancers tended to have an increased rate in people that had diabetes. So that certainly makes sense.” (C, 10:45)
  • Surprising correlation: skin cancer rates also higher.
  • Ongoing debate whether some GLP1/DPP4 drugs or metformin use influence cancer risk.
    • “Folks who had metformin (in ovarian cancer) actually had a higher survival rate.” (C, 11:26)

• Clinical Implication:

  • Reinforces the value of diabetes prevention: “It’s going to be another argument for primordial prevention in preventing people from ever developing diabetes.” (C, 12:03)

4. Serum Adiponectin and Metabolic Syndrome Incidence (ARIRANG Study)

— Article from June 2013 Diabetes Care
(10:25 – 13:28)

• Study Summary:

  • Prospective cohort, >2,000 adults, average 2.6 years’ follow-up.
  • Higher baseline adiponectin reduced incident metabolic syndrome:
    • Top quartile vs. lowest: OR 0.25 (men), OR 0.45 (women).

• Noteworthy Insights:

  • “The important point here, the take-home point, is that increased adiponectin levels are independent predictors for incident metabolic syndrome.” (B, 13:28)
  • Adiponectin secreted by adipose tissue, enhances insulin sensitivity.
  • Paradoxically, obesity leads to less adiponectin secretion.

• Outlook:

  • Anticipated future research on adiponectin’s impact in diabetes and obesity.

5. Mercury Exposure in Youth and Diabetes Risk

— Article from June 2013 Diabetes Care
(13:28 – 15:56)

• Study Summary:

  • Cohort of ~3,875 Americans (aged 20–32 in 1987), followed for 18 years.
  • Baseline toenail mercury levels measured; higher quintiles linked to 65% higher diabetes incidence.
    • “Higher levels of mercury exposure led to a 65% increase in the development of diabetes.” (B, 15:40)

• Reflections & Context:

  • Mercury exposure still rare; most common in high-fish diets (e.g., sushi eaters).
  • Anecdotes: Jeremy Piven’s “sushi-induced” mercury toxicity, historical references to “mad as a hatter” and Abraham Lincoln’s use of mercury compounds.
  • “…I think mercury itself is kind of an interesting thing, a dangerous thing… I’m not so sure that I’m going to use this as a diabetes prevention thing in my office.” (C, 18:18)

Notable Quotes and Memorable Moments

• On cognitive decline and diabetes:
  “A three times larger decline in information processing speed, and a four times larger decline in executive function among patients with diabetes at baseline is impressive and scary.” (B, 07:09)

• On waist circumference measurement consistency:
  “Using our own natural landmarks on our body makes it much easier to have consistent measurement…” (C, 04:34)

• On cancer risk and diabetes prevention:
  “It’s going to be another argument for primordial prevention in preventing people from ever developing diabetes, because we can hopefully keep them healthier down the road.” (C, 12:03)

• On adiponectin as an emerging predictor:
  “I think it’s a hormone that we’re probably going to be hearing a lot more about over the coming years…” (B, 14:27)

• On practical impact of mercury-diabetes research:
  “…I’m not so sure that I’m going to use this as a diabetes prevention thing in my office.” (C, 18:18)

Timestamps for Major Segments

• Waist circumference measurement – 00:56–03:54
• Type 2 diabetes & cognitive decline – 03:54–07:09
• Diabetes duration, insulin use & cancer – 07:09–10:25
• Adiponectin & metabolic syndrome – 10:25–13:28
• Mercury exposure & diabetes risk – 13:28–15:56

Summary/Table of Contents

1. Optimal waist circumference measurement for clinical assessment of risks — evidence leans toward mid-abdominal measure, though convenience and reproducibility are concerns.
2. Type 2 diabetes is associated with significant long-term cognitive decline — underlines additional consequences of diabetes and value of aggressive risk factor management.
3. Longer diabetes duration and insulin use correlate with higher cancer prevalence — clear trend, but causality remains open; emphasizes value of preventive strategies.
4. Higher adiponectin levels independently predict reduced metabolic syndrome risk — emerging biomarker and research target.
5. Mercury exposure in youth associated with higher diabetes risk — practical implications still unclear; remains more an epidemiologic curiosity than a clinical directive for now.

For article links and more information, visit www.diabetesjournals.org.