Podcast Summary:

Healthier World with Quest Diagnostics
Episode: The Insulin Resistance Revolution: The Key to Preventing Chronic Conditions
Date: November 4, 2024
Length: 17 minutes
Host: Dr. Mason Latsko (Quest Diagnostics)
Guest: Kenneth French, Clinical Consultant

Overview of the Episode

This episode tackles the growing epidemic of insulin resistance, framing it as the critical precursor to a wide range of chronic health conditions, including obesity, type 2 diabetes, cardiovascular disease, fatty liver disease, and more. Host Dr. Mason Latsko and guest Kenneth French discuss the development, detection, and implications of insulin resistance, emphasizing the importance of early intervention and advances in diagnostic tools—particularly Quest Diagnostics' novel insulin resistance panel.

Key Discussion Points and Insights

The Obesity Crisis and Insulin Resistance (01:10–02:59)

• Obesity rates have skyrocketed and are projected to reach 50% by 2030; one in four Americans may be morbidly obese.
• Obesity drives a range of secondary illnesses: kidney, liver, and heart disease.
• The underlying driver is insulin resistance, affecting more people than any other single health condition.
• Insulin resistance is not a new concept, with roots in the term "metabolic syndrome" identified in guidelines as far back as 2000.

Quote:

"Obesity in and of itself is not the link. The link is what's driving the obesity. And that is this condition called insulin resistance, which affects more individuals than any other condition." — Kenneth French (01:49)

The Continuum of Chronic Disease: From Health to Diabetes (02:59–05:07)

• Chronic disease is a continuum, not a switch; insulin resistance precedes prediabetes and diabetes by many years.
• During the insulin resistant years, the body needs increasing amounts of insulin to regulate glucose.
• External signs (elevated liver enzymes, weight gain, rising blood pressure, dyslipidemia) are often visible before changes in A1C or glucose.

Quote:

"Well, what's before prediabetes is the state of insulin resistance. And that's in and of itself, actually is where the problem lies." — Kenneth French (03:31)

Insulin Resistance: Mechanism and Diagnosis Challenges (05:07–07:45)

• In a healthy body, insulin efficiently regulates glucose after carbohydrate intake.
• Persistently high glucose forces the pancreas to produce more insulin, leading to cells becoming less responsive (insulin resistance).
• Diagnosis is difficult: traditional insulin testing lacks standardization; historical “gold standard” tests (like the euglycemic clamp) are impractical in routine practice.

Quote:

"A lot of clinicians don't realize that insulin has never been a standardized test... you could have three different laboratories run the quote unquote, same test, and you literally get three different results." — Kenneth French (06:12)

Advances in Diagnostics: The Insulin Resistance Panel (07:45–10:14)

• New assays, particularly liquid chromatography-tandem mass spectrometry, now allow for more precise measurement of insulin and its different forms.
• Quest Diagnostics, collaborating with academic experts, developed the insulin resistance (IR) panel with score.
  • Combines measurements of intact insulin and C-peptide to produce a score (1–100), indicating both presence and degree of insulin resistance.
  • Score interpretation:
    • 1–33: Normal insulin sensitivity
    • 34–66: 4x higher odds of insulin resistance

    • 66: 15x higher odds of insulin resistance

Quote:

"By using liquid chromatography tandem mass spec and measuring specifically the intact insulin and the C peptide simultaneously... we call now the insulin resistance panel with score." — Kenneth French (08:34)

Clinical Application: Using IR Panel to Guide Interventions (10:14–11:58)

• An individual may have “normal” A1C and glucose, but a high IR score reveals hidden risk.
• Treating insulin resistance early can lead to improvements in:
  • Dyslipidemia
  • Liver function enzymes
  • Kidney health
  • Blood pressure
  • Weight control
• Improvement might not show in A1C or glucose in the short-term, but reducing the IR score signals improved metabolic health.

Quote:

"...the glucose and A1C may not change at all. But when they look at the insulin resistance panel and score and see that that value went from 66 to 14, they know they had a positive impact." — Kenneth French (11:10)

Systemic Impact: Potential to Reverse or Prevent Chronic Illnesses (11:58–14:34)

• Lowering insulin resistance yields benefits across multiple organ systems.
• IR panel scores predict not only diabetes risk but also conditions like nonalcoholic fatty liver disease (now called metabolic dysfunction-associated steatotic liver disease).
• IR scores ≥31 or intact insulin ≥10.5 μU/mL in healthy people have an 80% positive predictive value for fatty liver disease.

Quote:

"What was remarkable is in normal healthy subjects, the IR panelist score, if the score was 31 or greater... that patient had a 80% positive predictive value for non alcoholic fatty liver disease." — Kenneth French (13:45)

Key Takeaways: The Insulin Resistance Revolution (15:04–16:34)

• Evaluate for insulin resistance early to prevent a domino effect of chronic diseases.
• Insulin resistance is treatable and reversible, not a new phenomenon.
• Solving insulin resistance could decrease the incidence of diabetes, kidney disease, fatty liver disease, hypertension, obesity, and some neurological and mood disorders.

Quote:

"Imagine the consequences of solving the insulin resistance problem for our population... you're reducing the burden of kidney disease... obesity epidemic... neurological and major depressive disorders where insulin resistance is a big play, all because we're addressing the root cause." — Kenneth French (15:31)

Notable Quotes & Memorable Moments (with Timestamps)

• “Obesity in and of itself is not the link. The link is what's driving the obesity. And that is this condition called insulin resistance...” — Kenneth French (01:49)
• “What's before prediabetes is the state of insulin resistance. And that's... where the problem lies.” — Kenneth French (03:31)
• “You could have three different laboratories run the quote unquote, same test, and you literally get three different results.” — Kenneth French (06:16)
• “By using liquid chromatography tandem mass spec and measuring specifically the intact insulin and the C peptide simultaneously...we call now the insulin resistance panel with score.” — Kenneth French (08:34)
• “When they look at the insulin resistance panel and score and see that that value went from 66 to 14, they know they had a positive impact.” — Kenneth French (11:10)
• “If the score was 31 or greater... that patient had a 80% positive predictive value for non alcoholic fatty liver disease.” — Kenneth French (13:45)
• “Solving insulin resistance... you're reducing the burden of kidney disease... obesity epidemic... neurological and major depressive disorders where insulin resistance is a big play, all because we're addressing the root cause.” — Kenneth French (15:31)

Timestamps for Key Segments

• 00:19–01:10: Introduction to episode’s focus and stakes of metabolic dysfunction
• 01:10–02:59: Link between obesity, metabolic dysfunction, and the history of insulin resistance
• 02:59–05:07: The disease continuum and how insulin resistance precedes recognizable diabetes
• 05:07–07:45: Clarifying insulin resistance physiology; issues with traditional diagnostic methods
• 07:45–10:14: Advances in testing: Quest’s insulin resistance panel and how it works
• 10:14–11:58: Clinical management based on IR panel scores; how improvements are tracked
• 11:58–14:34: Broader impacts of treating insulin resistance; prediction of fatty liver and other diseases
• 15:04–16:34: Takeaways and call to action for early identification and intervention

Final Thoughts

The episode makes a compelling case that insulin resistance is a treatable, reversible root cause of many of today’s most pressing chronic diseases. Quest Diagnostics' development of a standardized, practical insulin resistance assessment—through the IR panel with score—equips both clinicians and patients with a powerful, actionable tool to intervene earlier and more effectively, potentially shifting the healthcare paradigm from reaction to true prevention.