Monday, November 8, 2021

How common is remission of type 2 diabetes?

 - Jennifer Middleton, MD, MPH

Perhaps your patients with type 2 diabetes have also asked you if it's possible to "cure" their diabetes. The only method with an evidence base of doing so to date has been bariatric surgery, but a new study suggests that achieving remission from type 2 diabetes may be more common than previously thought. Using a national registry that included 99% of all persons in Scotland with a type 2 diabetes diagnosis, this study's authors examined hemoglobin A1c values throughout the 2019 calendar year and found that 4.8% decreased their A1c below 6.5%.

In this cohort of over 162,000 persons, the study authors identified several differences between the persons who achieved remission and those who did not:

Key differences in characteristics of people in remission in 2019 compared to people who were not in remission in 2019 were older age (70% of people in remission were aged ≥65, compared to 54% of people not in remission); greater weight loss between diagnosis of diabetes and 2019; lower proportions with previous prescriptions of GLT [glucose lowering therapy] (25% of people in remission had been prescribed GLT compared to 84% of people not in remission); lower mean HbA1c at diagnosis...; and higher prevalence of previous history of bariatric surgery (although overall numbers of people with a history of bariatric surgery were small). 

The authors hypothesize that "[i]t is possible that older people were diagnosed with diabetes with HbA1c values closer to diagnostic thresholds or after minor weight gain, and, therefore, only minor decreases in HbA1c or minor weight loss might be more likely to result in remission than among younger people.It's not surprising that patients who were able to lose weight (those in remission lost an average of 6.5 kg, or about 14 pounds) and/or who had lower A1cs to begin with were more likely to achieve remission. The lower prescriptions of glucose-lowering medications in the remission group likely relates to their overall lower A1cs to begin with. Bariatric surgery has already been demonstrated to help persons with type 2 diabetes achieve remission; a 2020 study found that nearly half of persons with type 2 diabetes achieved sustained remission after gastric bypass, though only 488 persons in the 2019 Scottish cohort had a history of bariatric surgery. 

The American Diabetes Association (ADA) released guidelines last month defining "remission" as an A1c < 6.5% "measured at least 3 months after cessation of glucose-lowering pharmacotherapy." They further recommend that:

  • A1c testing occur at least annually to confirm continued remission
  • Continued regular screening for retinal disease
  • Continued regular screening for kidney disease
  • Continued assessment and treatment of cardiovascular disease risk factors
Little patient-oriented outcomes that matter (POEM) data exists to back these recommendations. The guideline authors do cite this study demonstrating worsening of diabetic retinopathy in persons who achieved diabetes remission after bariatric surgery, though it's unclear whether the abrupt drop in blood glucose levels after surgery contributed to this worsening as compared to just continued retinopathy disease progression.

This Scottish study provides at least some sense regarding those persons more likely to achieve type 2 diabetes remission: older age, lower A1c to begin with, and able to sustain at least 6.5 kg of weight loss. You can read more at the AFP By Topic on Diabetes: Type 2, which includes a wealth of information on screening, prevention, and treatment.