Diabetes Core Update – September 2015

Podcast: Diabetes Core Update
Date: August 24, 2015
Hosts: Dr. Neil Skolnik & Dr. John J. Russell

Overview

In this episode, Dr. Neil Skolnik and Dr. John J. Russell discuss five recent clinically relevant articles from the American Diabetes Association’s journals. They examine critical updates in the management and understanding of diabetes, including glucose control in surgical patients, cognitive impairment in type 1 diabetes, complications related to SGLT2 inhibitors, energy balance with these medications, and lifestyle interventions to prevent gestational diabetes.

Key Discussion Points & Insights

1. Intensive vs. Conservative Glucose Control After Coronary Bypass Surgery

[00:54 – 02:35]

• Study Design: Randomized controlled trial from Diabetes Care on patients (diabetic and non-diabetic) undergoing coronary artery bypass grafting (CABG).
• Intervention: Compared intensive glucose target (100–140 mg/dL) vs. conservative glucose target (141–180 mg/dL).
• Outcomes: No significant differences in composite complications (mortality, wound infection, pneumonia, bacteremia, respiratory failure, acute kidney injury, cardiovascular events) between the two groups.
• Key Point: Even tighter glucose control postoperatively does not result in better outcomes compared to moderate control.

Notable Commentary:

• Dr. Russell:

  “Tighter glucose control really doesn’t lead to better outcomes… I think we really need to focus on other things instead of having immaculate blood sugar control in our ICUs after procedures.” [02:35]

• Emphasis on the dangers of over-tight control, particularly as patients transition out of the hospital, highlighting risks of hypoglycemia.

2. Cognitive Impairment in Type 1 Diabetes

[02:36 – 05:52]

• Study Details: Examined 97 adults with childhood-onset type 1 diabetes (duration ~41 years) vs. 138 controls, using extensive neuropsychological testing.
• Key Findings: Clinically relevant cognitive impairment was five times higher in adults with type 1 diabetes than in controls (28% vs. ~5%).
• Risk Factors: Prolonged poor glycemic control (14-year average A1C >7.5%), presence of proliferative retinopathy, polyneuropathy, higher BMI, and abnormal ankle-brachial index.

Notable Commentary:

• Dr. Skolnik:

  “The fact that 28% of patients with type 1 diabetes by middle age… suffer from identifiable cognitive impairment is scary. That’s the same number that the average 85-year-old non-diabetic cohort has.” [05:15]

• Emphasizes need for meticulous, long-term glycemic control and patient education about additional risks.

3. Euglycemic DKA with SGLT2 Inhibitors

[05:53 – 11:31]

• Background: Two papers discussed:
  1. Series of 13 euglycemic DKA episodes (DKA with normal/near-normal blood glucose) in 9 patients on SGLT2 inhibitors (mostly type 1 diabetes, some type 2).
  2. Canagliflozin clinical program: 17,596 patients, 12 cases of DKA (0.07%); most on insulin, mostly with high glucose; minority possibly type 1 or LADA.
• Clinical Pearl: Absence of significant hyperglycemia delayed DKA recognition and appropriate treatment.

Memorable Moment:

• Dr. Russell:

  “I’m not sure most of us as the average clinician would leap to think that someone had a euglycemic DKA… This is a nice warning point for all of us in this new class of medicine.” [11:32]

Practical Application:

• Consider holding SGLT2 inhibitors a week to 10 days before surgery to prevent postoperative DKA (most cases occurred postoperatively).
• Increase vigilance for unexplained acidosis in patients on SGLT2 inhibitors—even with “normal” sugars.

4. Energy Balance and SGLT2 Inhibitors: Why Weight Loss Plateaus

[13:31 – 15:33]

• Study Details: 86 type 2 diabetics took empagliflozin for 90 weeks. Though urine glucose loss (“glucosuria”) was equivalent to ~200 Kcal/day (predicted ~11.3 kg loss), actual weight loss was only ~3.2 kg (~29%).
• Conclusion: Patients compensated by increasing calorie intake (~269 Kcal/day).

Notable Commentary:

• Dr. Skolnik:

  “What this study shows… only a third of the predicted weight loss… occurs by the end of the year. Where it’s made up is increased intake. The mechanisms for weight loss and maintaining weight are complex.” [15:33]

• SGLT2 inhibitors lack the appetite-suppressing effect seen with GLP-1 agents—behavioral and dietary measures remain crucial for weight loss.

5. Physical Activity, Healthy Eating, and Risk of Gestational Diabetes

[15:34 – 18:39]

• Study Design: European multicenter RCT with pregnant women (BMI >29, no GDM at <20 weeks). Randomized to healthy eating, physical activity (PA), or both.
• Findings: 32% developed GDM by 35-37 weeks; only 20% reached <5 kg gestational weight gain. Healthy eating group gained less weight and had lower fasting glucose than PA group. No additive effect from combining interventions.
• Message: Dietary intervention started earlier in pregnancy is most beneficial.

Notable Commentary:

• Dr. Russell:

  “Let’s find the folks who have a BMI greater than 29 at the start of their pregnancy and start making some interventions… Some very benign ways with diet and exercise.” [18:40]

Conclusion & Takeaways

• Perioperative glucose control: Moderate targets are adequate; avoid overtightening and potential harm.
• Cognitive impairment: High risk in longstanding type 1 diabetes—intensive long-term control is crucial.
• SGLT2 inhibitors: Be alert for euglycemic DKA, especially perioperatively; consider withholding around surgeries.
• Weight management with SGLT2 inhibitors: Actual weight loss is blunted by compensatory intake—dietary counseling is essential.
• Gestational diabetes prevention: Early dietary (rather than physical activity) interventions are most effective for at-risk pregnancies.

Memorable Quotes

• On glucose control post-CABG:

  "Tighter glucose control really doesn't lead to better outcomes... focus on other things instead." – Dr. Russell [02:35]

• On cognitive impairment:

  "28% of type 1 diabetics by middle age... that's the average 85-year-old non-diabetic." – Dr. Skolnik [05:15]

• On euglycemic DKA warning:

  "This is a nice warning point for all of us in this new class of medicine." – Dr. Russell [11:32]

• On SGLT2 weight plateau:

  "Only a third of the predicted weight loss... occurs by the end of the year." – Dr. Skolnik [15:33]

• On gestational diabetes prevention:

  "Let's find the folks who have a BMI greater than 29... and start making some interventions... at the beginning of their pregnancy." – Dr. Russell [18:40]

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