Do you discontinue a type 2 diabetes (T2D) diagnosis when a patient's Hemoglobin A1c (HbA1c) level is less than 6.5%?

Type 2 Diabetes Diagnosis Status with HbA1c Below 6.5%

No, the type 2 diabetes diagnosis should not be discontinued when a patient's HbA1c falls below 6.5%. 1, 2

Understanding Diabetes Diagnosis and Classification

Type 2 diabetes is a chronic condition that persists even when glycemic control improves. According to the American College of Physicians (ACP) guidelines, achieving an HbA1c below 6.5% represents successful treatment, not the absence of disease 1.

The diagnosis of diabetes is established when:

• HbA1c ≥ 6.5% (using NGSP certified method)
• Fasting plasma glucose ≥ 126 mg/dL (7.0 mmol/L)
• 2-hour plasma glucose ≥ 200 mg/dL (11.1 mmol/L) during OGTT
• Random plasma glucose ≥ 200 mg/dL with classic symptoms 1

Once diagnosed, diabetes remains a lifelong condition requiring ongoing monitoring and management.

Management of Patients with Well-Controlled Diabetes

When a patient achieves an HbA1c below 6.5% on medication, the ACP recommends:

1. Consider deintensifying therapy by:

   • Reducing medication dosage
   • Removing a medication if on multiple agents
   • Potentially discontinuing pharmacologic treatment 1, 2

2. Do not remove the diagnosis as this could:

   • Lead to discontinuation of necessary monitoring
   • Result in loss of appropriate follow-up
   • Create insurance coverage issues for diabetes care
   • Cause confusion if glycemic control worsens later

Evidence on Glycemic Targets and Outcomes

The ACCORD trial demonstrated that targeting HbA1c below 6.5% not only failed to improve clinical outcomes but was associated with increased mortality 1, 2. This suggests that while good glycemic control is beneficial, excessively tight control may be harmful.

A nested case-control study found that patients with type 2 diabetes who achieved mean A1C levels ≤6% had a 20% increased risk of cardiovascular events compared to those with A1C levels between >6-8% 3.

Special Considerations for Different Patient Groups

Younger Patients with Recent-Onset Diabetes

For younger patients with recent-onset diabetes and no significant comorbidities, maintaining good glycemic control is important for preventing long-term complications, but the diagnosis remains 1.

Older Adults or Those with Multiple Comorbidities

For patients with life expectancy <10 years due to advanced age (≥80 years), nursing home residence, or chronic conditions, the focus should be on treating symptoms rather than targeting specific HbA1c levels 1, 2.

Practical Approach to Management

1. When HbA1c falls below 6.5%:

   • Maintain the diabetes diagnosis
   • Consider medication reduction if appropriate
   • Continue regular monitoring (though possibly less frequently)
   • Emphasize ongoing lifestyle modifications

2. If patient achieves HbA1c <6.5% through lifestyle alone:

   • Diabetes diagnosis remains
   • Continue monitoring to detect any worsening
   • Reinforce successful lifestyle changes

Common Pitfalls to Avoid

• Removing the diagnosis when HbA1c normalizes, which can lead to discontinuation of necessary monitoring
• Maintaining intensive therapy despite HbA1c <6.5%, which increases risk of hypoglycemia and other adverse effects
• Assuming permanent remission without continued monitoring
• Neglecting cardiovascular risk reduction which remains important regardless of glycemic control

The UKPDS study demonstrated that the majority of patients with type 2 diabetes experience progressive deterioration of glycemic control over time, with only about 25% maintaining target HbA1c levels after 9 years of monotherapy 4. This underscores the importance of maintaining the diagnosis even during periods of good control.