EDITORIAL

Disclosure: The authors, Philip R. Schauer, MD, and John P. Kirwan, PhD, are co-investigators and co-authors of the ARMMS-T2D study discussed in this editorial; Dr. Kirwan is a principal investigator of the study. Their financial disclosures, as listed in the study, appear at the end.

Study cited: Simonson DC, Cummings DE, Schauer PR, et al. Predictors of Type 2 Diabetes Remission and Relapse After Metabolic-Bariatric Surgery or Medical-Lifestyle Therapy in the ARMMS-T2D Study. Diabetes Care. 2026;49(12). doi:10.2337/dc26-1070

Editor's note: This editorial was approved for publication by a vote of the MBS Digest editorial board (a majority of its voting editors). The views expressed are the authors'.

For decades, treatment of type 2 diabetes (T2D) has focused on controlling hyperglycemia, preventing complications, and slowing disease progression. Yet the ultimate goal of disease-modifying therapy should be more ambitious: durable remission, approaching a functional cure. International consensus defines remission as HbA1c <6.5% measured at least three months after stopping glucose-lowering medications.[1] The landmark ARMMS-T2D study shows that metabolic surgery, particularly Roux-en-Y gastric bypass (RYGB), offers a substantial opportunity to achieve this goal, and that the likelihood of remission falls the longer diabetes has been present.[2]

ARMMS-T2D is arguably unique for its breadth and duration. By combining four randomized clinical trials, it evaluated 262 patients assigned to intensive medical-lifestyle therapy or to three metabolic operations: RYGB, sleeve gastrectomy (SG), or adjustable gastric banding (AGB), with a median follow-up of 11 years and up to 14 years. The study was designed and powered mainly to compare surgery overall with medical-lifestyle therapy; comparisons among the three operations were secondary analyses.

The results are striking. Diabetes remission occurred in 58% of surgical patients, compared with only 3% in those receiving medical-lifestyle treatment. RYGB achieved the highest cumulative remission rate (69%), followed by SG (52%) and AGB (35%), and new remissions continued to appear over the longest period after RYGB. Remission was not permanent for everyone: among patients who remitted after surgery, relapse was predicted by longer baseline diabetes duration and more glucose-lowering medication classes, and did not differ significantly by operation. Previous ARMMS reports have established superior glycemic control and weight loss after metabolic surgery.

Perhaps the most consequential finding concerns the timing of surgery. In multivariate analysis, the baseline predictors of remission were shorter diabetes duration and absence of insulin therapy, and greater weight loss at one year also predicted remission. In univariate analyses, additional predictors included fewer glucose-lowering medication classes, higher fasting C-peptide and insulin, and, marginally, greater baseline body weight; baseline BMI did not predict remission. Diabetes duration, insulin use, medication burden, and C-peptide are likely proxies for insulin resistance or inadequate β-cell function, a defining feature of later stages of T2D, when even surgery does not reliably produce remission. Physiologically, remission requires both improved insulin sensitivity and sufficient residual β-cell secretory capacity to respond to it. These findings are consistent with a window in which β-cell function remains sufficient to permit remission, although ARMMS-T2D did not directly assess islet structure.

Timing matters. Cumulative remission occurred in 75% of patients with diabetes duration of 1–4.9 years, compared with 59% at 5–9.9 years and only 36% after ≥10 years (P = 0.002). Although observational associations within randomized treatment groups cannot prove that earlier surgery guarantees remission, they argue for considering surgery relatively early in the course of T2D, while remission is still likely to be achievable.

Eligibility should reflect metabolic disease severity, not BMI alone. In ARMMS-T2D, 37% of participants had a baseline BMI below 35 kg/m², and baseline BMI did not predict remission. Current international guidelines recommend metabolic surgery at a BMI ≥35 kg/m² and support consideration at a BMI of 30–34.9 kg/m² when T2D remains inadequately controlled despite nonsurgical treatment.[3] This aligns with the Lancet Diabetes & Endocrinology Commission on clinical obesity, which calls for diagnosis and treatment decisions based on organ dysfunction rather than BMI alone.[4] Early referral should facilitate informed decision-making, not require exhausting every available medication.

Intensive dietary intervention can produce remission, particularly in recently diagnosed diabetes. However, the DiRECT trial showed that sustaining remission is difficult, with only 13% in remission at five years.[5] In ARMMS-T2D, remission at five years was 26% in the surgical group, even though participants had longstanding disease (mean duration 8.5 years, 45% taking insulin). Metabolic surgery remains the best-established intervention for achieving substantial remission rates beyond five years, and ARMMS-T2D provides the first randomized-trial data showing remission lasting more than a decade with any intervention.

Even temporary remission may confer lasting cardiovascular benefits. The Swedish Obese Subjects study linked diabetes remission after surgery to reduced cardiovascular mortality and macrovascular complications.[6] Remission is therefore more than freedom from medication; it may represent a life-extending achievement. ARMMS-T2D itself did not measure these outcomes.

Operative risks and lifelong nutritional surveillance remain important considerations, and safety was not the focus of this analysis. Nevertheless, surgery is too often reserved as a last resort, after years of escalating medications and a growing duration of diabetes.

This paradigm must change. Physicians managing T2D have a responsibility to inform eligible patients early that metabolic surgery offers a meaningful chance of durable remission, and that this chance declines with longer diabetes duration. Modern pharmacotherapy remains important, but delaying surgical discussion until medical treatment fails may reduce the likelihood of remission. ARMMS-T2D began before potent incretin-based therapies were widely used, and whether early surgery compares with early tirzepatide or semaglutide for durable remission is an open question that warrants a randomized trial.

Intervene early with metabolic surgery, or risk missing the golden opportunity for diabetes remission.

1. Riddle MC, Cefalu WT, Evans PH, et al. Consensus Report: Definition and Interpretation of Remission in Type 2 Diabetes. Diabetes Care. 2021;44(10):2438–2444. doi:10.2337/dci21-0034.

2. Simonson DC, Cummings DE, Schauer PR, et al. Predictors of Type 2 Diabetes Remission and Relapse After Metabolic-Bariatric Surgery or Medical-Lifestyle Therapy in the ARMMS-T2D Study. Diabetes Care. 2026;49(12). doi:10.2337/dc26-1070.

3. Eisenberg D, Shikora SA, Aarts E, et al. 2022 ASMBS and IFSO Indications for Metabolic and Bariatric Surgery. Surg Obes Relat Dis. 2022;18(12):1345–1356. doi:10.1016/j.soard.2022.08.013.

4. Rubino F, Cummings DE, Eckel RH, et al. Definition and diagnostic criteria of clinical obesity. Lancet Diabetes Endocrinol. 2025;13(3):221–262. doi:10.1016/S2213-8587(24)00316-4.

5. Lean ME, Leslie WS, Barnes AC, et al. Five-year follow-up of the randomized Diabetes Remission Clinical Trial (DiRECT) of continued support for weight loss maintenance in the UK: an extension study. Lancet Diabetes Endocrinol. 2024;12(4):233–246. doi:10.1016/S2213-8587(23)00385-6.

6. Carlsson LMS, Carlsson B, Jacobson P, et al. Mortality in relation to diabetes remission in Swedish Obese Subjects—a prospective cohort study. Int J Surg. 2024;110(10):6581–6590. doi:10.1097/JS9.0000000000001807.

The authors are co-investigators and co-authors of the ARMMS-T2D study discussed in this editorial. J.P.K. is a principal investigator of ARMMS-T2D.

As listed in the study (Diabetes Care 2026;49(12), Duality of Interest), P.R.S.: has received research grants from Ethicon and Medtronic; personal consulting fees or honoraria from GI Dynamics, Keyron, Persona, Mediflix, Metabolic Health International, Eli Lilly, Heron, Novo Nordisk, and Klens; served on scientific advisory boards for SE Healthcare Board of Directors, GI Dynamics, Keyron, Persona, and Mediflix; and has ownership interests in SE Healthcare LLC, Mediflix, and Metabolic Health International, LTD.

As listed in the study, J.P.K.: received research grants from NIH NIDDK (R01 DK108089) related to the submitted work, and from the National Institute of General Medical Sciences (U54 GM104940) for unrelated work; and received consulting fees from Novo Nordisk, honoraria from Annual Reviews of Nutrition and Ball State, and travel expenses from Annual Reviews of Nutrition, Ball State, and LA Office of Tourism, all unrelated to the submitted work.

Study funding, as listed in the study: STAMPEDE was supported by an investigator-initiated grant from Ethicon Endo-Surgery and in-kind support from LifeScan. SLIMM-T2D was funded by in-kind support from LifeScan, Nestlé, and Novo Nordisk. STAMPEDE, SLIMM-T2D, TRIABETES, and CROSSROADS received bridge funding from Covidien (now Medtronic) and Ethicon in preparation for the current NIH-funded long-term follow-up and analysis.