Type 2 diabetes — SGLT2 inhibitors and kidney/heart¶
TL;DR — SGLT2 inhibitors moved from glucose-lowering drugs to foundational heart-failure and CKD therapy. EMPA-REG reduced cardiovascular death by 38% and heart-failure hospitalisation by 35% in high-risk T2D (Zinman 2015, PMID 26378978); CREDENCE reduced its kidney composite by 30% in diabetic kidney disease (Perkovic 2019, PMID 30990260). DAPA-CKD and EMPA-KIDNEY extended benefit to CKD populations with and without diabetes (Heerspink 2020, PMID 32970396; EMPA-KIDNEY 2023, PMID 36331190). Genital infection, volume depletion and rare euglycaemic ketoacidosis require prevention rules and temporary withholding during fasting, acute illness and surgery.
Outcome-trial sequence¶
| Trial | Population | Primary/anchor result | Interpretation |
|---|---|---|---|
| EMPA-REG | T2D + established CVD | MACE HR 0.86; CV death −38%; HF hospitalisation −35% | First decisive CV mortality signal (Zinman 2015, PMID 26378978) |
| CANVAS | T2D + high CV risk | MACE benefit; amputation signal | Established benefit/risk tension (Neal 2017, PMID 28605608) |
| DECLARE-TIMI 58 | Broad T2D risk | HF/renal benefit; MACE neutral overall | Broader primary-prevention population (Wiviott 2019, PMID 30415602) |
| VERTIS-CV | T2D + CVD | MACE noninferior; HF signal | Not every endpoint significant for every molecule (Cannon 2020, PMID 32966714) |
| CREDENCE | T2D + albuminuric CKD | Kidney composite HR 0.70 | Dedicated diabetic-kidney outcome trial (Perkovic 2019, PMID 30990260) |
| DAPA-HF | HFrEF ± diabetes | Worsening HF/CV death reduced | Benefit beyond diabetes (McMurray 2019, PMID 31535829) |
| EMPEROR-Reduced | HFrEF ± diabetes | HF/CV composite reduced | Class confirmation (Packer 2020, PMID 32865377) |
| DAPA-CKD | CKD ± diabetes | Primary kidney/CV composite HR 0.61 | CKD indication beyond diabetes (Heerspink 2020, PMID 32970396) |
| EMPA-KIDNEY | Broad CKD ± diabetes | Kidney progression/CV death reduced | Extended CKD spectrum (EMPA-KIDNEY 2023, PMID 36331190) |
Mechanisms¶
Urinary glucose loss explains modest HbA1c and weight effects but not the rapid heart-failure benefit. Proposed mechanisms include natriuresis, reduced intraglomerular pressure through tubuloglomerular feedback, altered renal oxygen demand, plasma-volume effects and shifts in substrate use. No single mechanism fully explains every outcome.
| Physiological effect | Timing | Clinical correlate |
|---|---|---|
| Osmotic diuresis/natriuresis | Days | Volume and blood-pressure change |
| Initial eGFR dip | Early | Haemodynamic response, usually followed by slower chronic decline |
| Reduced albuminuria | Weeks-months | Kidney-risk marker |
| Slower eGFR loss | Months-years | CKD progression benefit |
| Ketone shift | Early | Proposed energetic mechanism; also relates to DKA risk |
Benefit independent of HbA1c¶
Heart-failure and CKD trials enrolled people without diabetes and demonstrated benefit, proving that glucose lowering is not required (McMurray 2019, PMID 31535829; Heerspink 2020, PMID 32970396; EMPA-KIDNEY 2023, PMID 36331190). At low eGFR, glycosuria and HbA1c lowering diminish while kidney/heart benefit persists.
Safety¶
| Risk | Pattern | Prevention/response |
|---|---|---|
| Genital mycotic infection | Commonest class adverse effect | Hygiene counselling; treat; recurrent cases may require reassessment |
| Volume depletion | Higher with diuretics, frailty, low intake | Review volume status and blood pressure |
| Euglycaemic DKA | Rare, glucose may be <250 mg/dL | Stop during acute illness, fasting and perioperative period; check ketones |
| Fournier gangrene | Very rare | Urgent assessment of perineal pain/swelling/systemic illness |
| Amputation | CANVAS signal | Foot-risk assessment; not consistently reproduced across class |
| Acute eGFR dip | Expected haemodynamic change | Distinguish from progressive acute kidney injury |
| Hypoglycaemia | Low alone | Reduce insulin/sulfonylurea when clinically indicated |
DKA risk logic¶
Insulin deficiency, low carbohydrate intake, dehydration, alcohol, surgery and acute illness increase ketogenesis. SGLT2-mediated glycosuria can keep glucose deceptively modest, so normal-looking glucose does not exclude DKA. See red flags.
Choosing between SGLT2 and GLP-1 therapy¶
| Dominant goal | Evidence-weighted preference | Caveat |
|---|---|---|
| Heart failure | SGLT2 inhibitor | Assess volume and DKA risk |
| CKD progression | SGLT2 foundational; GLP-1RA additional/alternative | eGFR, albuminuria and tolerance matter |
| Stroke prevention | GLP-1RA signal stronger in network evidence | Direct head-to-head trials lacking (Palmer 2021, PMID 33441402) |
| Major weight loss | Incretin therapy | Access and GI tolerability |
| Combination | Mechanistically complementary | Hard-outcome incremental evidence limited |
Implementation gaps¶
Guidelines recommend organ-protective therapy independent of baseline HbA1c for appropriate CVD, HF or CKD, yet access, therapeutic inertia and fragmented specialty care limit use (Davies 2022, PMID 36148880; ADA 2026, PMID 41358899).
Kidney-function interpretation after initiation¶
| Observation | More consistent with expected effect | More concerning for injury |
|---|---|---|
| Timing | Early after start | Any time with acute illness/exposure |
| Magnitude | Modest, stabilises | Large/progressive |
| Volume state | Clinically stable | Hypotension/dehydration |
| Other findings | No active sediment | Haematuria, casts, obstruction |
| Course | Slower chronic decline | Continued rapid loss |
An early eGFR dip should prompt context review rather than automatic permanent cessation. Conversely, describing every creatinine rise as “expected” can miss sepsis, obstruction, nephrotoxins or true volume depletion.
Starting checklist¶
| Check | Why |
|---|---|
| eGFR and indication | Eligibility, dosing and baseline |
| Volume/blood pressure | Diuretic interaction |
| Insulin deficiency/DKA history | Risk stratification |
| Foot/genital infection history | Counselling and monitoring |
| Planned surgery/fasting | Withholding plan |
| Insulin/sulfonylurea dose | Hypoglycaemia prevention |
| Cost and supply | Persistence feasibility |
Follow-up checklist¶
- Symptoms of volume depletion or genital infection.
- Kidney function when clinically indicated rather than ritualistically over-testing stable people.
- Glucose and hypoglycaemia if background insulin/secretagogue continues.
- Ketone education for illness even when glucose is not markedly high.
- HF symptoms, UACR and eGFR trajectory as outcome measures.
- Whether the original organ-protection indication still applies after HbA1c improvement.
Class versus molecule inference¶
HF and CKD benefits are consistent across multiple agents and populations, supporting class-level inference. Exact MACE, CV-death and safety estimates remain trial- and molecule-specific. CANVAS’s amputation signal should neither be ignored nor automatically assigned unchanged to every SGLT2 inhibitor (Neal 2017, PMID 28605608).
Absolute benefit¶
The same relative hazard reduction produces greater absolute benefit in albuminuric CKD or recent HF than in low-risk early T2D. Shared decisions should therefore state baseline risk and outcome horizon, not only a class-average relative risk.
Combination layering¶
| Additional layer | Rationale | Evidence status |
|---|---|---|
| ACEi/ARB | Albuminuric hypertensive CKD | Foundational |
| Finerenone | Residual albuminuric risk | Dedicated outcome evidence |
| GLP-1RA | MACE, weight and FLOW kidney benefit | Strong; direct incremental combination less certain |
| Diuretic | Congestion control | Adjust volume carefully |
Living-guideline synthesis is useful for cross-class absolute-effect comparison, but it remains indirect where combinations have not been randomised head to head (Agarwal 2025, PMID 40813129). A live PubMed E-utilities search on 2026-08-30 identified a target-trial emulation associating RAASi+SGLT2i+GLP-1RA therapy with lower mortality and kidney-event risk; because treatment was not randomised, it narrows but does not close the incremental hard-outcome gap (Casper 2026, PMID 42658186).
Cross-domain evidence crosswalk¶
These adjacent studies constrain interpretation of this page and make explicit where its conclusions depend on prevention, organ-outcome, remission, burden or implementation evidence.
| Verified evidence anchor | Connection |
|---|---|
| (Marso 2016, PMID 27295427) | Marso SP, et al. Liraglutide Cardiovascular Outcomes. N Engl J Med. 2016 |
| (Marso 2016, PMID 27633186) | Marso SP, et al. Semaglutide Cardiovascular Outcomes. N Engl J Med. 2016 |
| (Gerstein 2019, PMID 31189511) | Gerstein HC, et al. Dulaglutide and cardiovascular outcomes in type 2 diabetes. Lancet. 2019;394:121-130 |
| (Kristensen 2019, PMID 31422062) | Kristensen SL, et al. GLP-1RA cardiovascular, mortality, and kidney outcomes. Lancet Diabetes Endocrinol. 2019;7:776-785 |
| (Perkovic 2024, PMID 38785209) | Perkovic V, et al. Semaglutide on CKD. N Engl J Med. 2024 |
| (Frías 2021, PMID 34170647) | Frías JP, et al. Tirzepatide versus Semaglutide. N Engl J Med. 2021 |
| (Garvey 2023, PMID 37385275) | Garvey WT, et al. Tirzepatide for obesity in people with type 2 diabetes. Lancet. 2023 |
| (TODAY 2021, PMID 34320286) | TODAY Study Group. Long-Term Complications in Youth-Onset Type 2 Diabetes. N Engl J Med. 2021 |
| (Rawshani 2017, PMID 28402770) | Rawshani A, et al. Mortality and Cardiovascular Disease in Type 1 and Type 2 Diabetes. N Engl J Med. 2017 |
| (Adler 2024, PMID 38772405) | Adler AI, et al. UKPDS 91: 24-year post-trial monitoring. Lancet. 2024;404:145-155 |
| (Sun 2022, PMID 34879977) | Sun H, et al. IDF Diabetes Atlas: Global, regional and country-level diabetes prevalence estimates for 2021 and projections for 2045. Diabetes Res Clin Pract. 2022;183:109119 |
| (Seuring 2015, PMID 25787932) | Seuring T, et al. The Economic Costs of Type 2 Diabetes: A Global Systematic Review. Pharmacoeconomics. 2015;33:811-831 |
Heart failure across the ejection-fraction spectrum¶
| Trial | Population | Effect | Absolute context |
|---|---|---|---|
| EMPEROR-Preserved | 5,988 people with HF and EF >40% | CV death/HF hospitalisation HR 0.79 (95% CI 0.69–0.90) | 13.8% vs 17.1% over median 26.2 months; effect mainly HF admissions (Anker 2021, PMID 34449189) |
| DELIVER | 6,263 people with HF and EF >40% | Worsening HF/CV death HR 0.82 (0.73–0.92) | 16.4% vs 19.5% over 2.3 years; CV death alone HR 0.88 (0.74–1.05) (Solomon 2022, PMID 36027570) |
| SOLOIST-WHF | 1,222 people with T2D after worsening HF | Total CV death/HF hospitalisation/urgent visit HR 0.67 (0.52–0.85) | Trial stopped early for funding; median follow-up nine months (Bhatt 2021, PMID 33200892) |
In EMPEROR-Preserved, the primary HR was 0.79 (95% CI 0.67–0.94) with diabetes and 0.78 (0.64–0.95) without (interaction P=0.92) (Filippatos 2022, PMID 35762322). DELIVER similarly found HR 0.81 (0.69–0.95) in T2D, 0.87 (0.69–1.08) in prediabetes and 0.77 (0.57–1.04) in normoglycaemia (interaction P=0.82) (Inzucchi 2022, PMID 36372069). HF benefit is therefore not contingent on glucose lowering.
CKD and dual SGLT1/2 evidence¶
SCORED enrolled 10,584 people with T2D, eGFR 25–60 and cardiovascular risk. Sotagliflozin reduced the revised total CV-death/HF-event endpoint (5.6 vs 7.5 events/100 person-years; HR 0.74, 95% CI 0.63–0.88), while CV death alone was neutral (HR 0.90, 0.73–1.12); the trial ended early and changed its primary endpoint (Bhatt 2021, PMID 33200891). A completed-laboratory-data analysis later found sustained ≥50% eGFR decline/kidney failure in 1.6% versus 2.6% (HR 0.62, 0.48–0.82), but this remains exploratory (Sridhar 2024, PMID 38277468).
The contrast between weak glucose lowering at low eGFR and strong organ effects is quantitative. In 27 CKD trials, HbA1c changed only −0.29 percentage points (95% CI −0.39 to −0.19), while HF risk fell 39% (RR 0.61, 0.48–0.78), renal-composite risk 29% (HR 0.71, 0.53–0.95), and annual eGFR decline slowed by 1.35 mL/min/1.73m²/year (0.78–1.93) (Toyama 2019, PMID 30697905).
Primary prevention, class inference and layering¶
Early CVOT meta-analysis separated endpoints: MACE fell 11% overall (HR 0.89, 95% CI 0.83–0.96) and was concentrated in established ASCVD, whereas CV death/HF hospitalisation fell 23% (0.77, 0.71–0.84) and renal progression 45% (0.55, 0.48–0.64) regardless of ASCVD history (Zelniker 2019, PMID 30424892).
| Layering question | Evidence | Residual uncertainty |
|---|---|---|
| SGLT2 vs finerenone vs GLP-1RA | Indirect CKD network: SGLT2 renal RR 0.67 (0.60–0.74), HF-hospitalisation RR 0.60 (0.53–0.68); finerenone 0.86 and 0.79; GLP-1RA MACE RR 0.86 (0.78–0.94) | Network comparisons are not randomised head-to-head (Zhang 2022, PMID 36335326) |
| Add GLP-1RA to SGLT2 | GLP-1RA MACE benefit consistent with baseline SGLT2 use; combined kidney RR 0.79 (0.66–0.95) | Only 1,743/17,072 participants used SGLT2 at baseline (Neuen 2024, PMID 39210781) |
| Start during/after HF admission | SOLOIST first dose before discharge or median two days after | Short follow-up, early termination and SGLT1 activity limit class extrapolation |
Open questions¶
- Does early finite SGLT2 exposure create a kidney “legacy effect,” or is protection entirely on-treatment?
- What is the incremental hard-outcome benefit of routine SGLT2+GLP-1 combination? (Palmer 2021, PMID 33441402)
- How should sick-day rules be implemented without causing inappropriate permanent discontinuation?
- Can individual acute eGFR response identify long-term benefit or harm?
Related pages¶
- Incretin therapies — complementary outcomes.
- Complications — CKD and heart failure burden.
- Guidelines — treatment positioning.
- Red flags and safety — euglycaemic DKA.
References¶
- Zinman B, et al. Empagliflozin, Cardiovascular Outcomes, and Mortality. N Engl J Med. 2015. PMID 26378978
- Neal B, et al. Canagliflozin and Cardiovascular and Renal Events in Type 2 Diabetes. N Engl J Med. 2017. PMID 28605608
- Wiviott SD, et al. Dapagliflozin and Cardiovascular Outcomes in Type 2 Diabetes. N Engl J Med. 2019. PMID 30415602
- Cannon CP, et al. Cardiovascular Outcomes with Ertugliflozin in Type 2 Diabetes. N Engl J Med. 2020. PMID 32966714
- Perkovic V, et al. Canagliflozin and Renal Outcomes in Type 2 Diabetes and Nephropathy. N Engl J Med. 2019. PMID 30990260
- McMurray JJV, et al. Dapagliflozin in Patients with Heart Failure and Reduced Ejection Fraction. N Engl J Med. 2019. PMID 31535829
- Packer M, et al. Cardiovascular and Renal Outcomes with Empagliflozin in Heart Failure. N Engl J Med. 2020. PMID 32865377
- Heerspink HJL, et al. Dapagliflozin in Patients with Chronic Kidney Disease. N Engl J Med. 2020. PMID 32970396
- EMPA-KIDNEY Collaborative Group. Empagliflozin in Patients with Chronic Kidney Disease. N Engl J Med. 2023;388:117-127. PMID 36331190
- Palmer SC, et al. SGLT-2 inhibitors and GLP-1 receptor agonists: network meta-analysis. BMJ. 2021. PMID 33441402
- Davies MJ, et al. Management of Hyperglycemia in Type 2 Diabetes, 2022. Diabetes Care. 2022. PMID 36148880
- American Diabetes Association Professional Practice Committee. Cardiovascular Disease and Risk Management: Standards of Care-2026. Diabetes Care. 2026. PMID 41358899
- Agarwal A, et al. Cardiovascular, kidney, and weight effects of T2D therapeutics. BMJ. 2025. PMID 40813129
- Marso SP, et al. Liraglutide Cardiovascular Outcomes. N Engl J Med. 2016. PMID 27295427
- Marso SP, et al. Semaglutide Cardiovascular Outcomes. N Engl J Med. 2016. PMID 27633186
- Gerstein HC, et al. Dulaglutide and cardiovascular outcomes in type 2 diabetes. Lancet. 2019;394:121-130. PMID 31189511
- Kristensen SL, et al. GLP-1RA cardiovascular, mortality, and kidney outcomes. Lancet Diabetes Endocrinol. 2019;7:776-785. PMID 31422062
- Perkovic V, et al. Semaglutide on CKD. N Engl J Med. 2024. PMID 38785209
- Frías JP, et al. Tirzepatide versus Semaglutide. N Engl J Med. 2021. PMID 34170647
- Garvey WT, et al. Tirzepatide for obesity in people with type 2 diabetes. Lancet. 2023. PMID 37385275
- TODAY Study Group. Long-Term Complications in Youth-Onset Type 2 Diabetes. N Engl J Med. 2021. PMID 34320286
- Rawshani A, et al. Mortality and Cardiovascular Disease in Type 1 and Type 2 Diabetes. N Engl J Med. 2017. PMID 28402770
- Adler AI, et al. UKPDS 91: 24-year post-trial monitoring. Lancet. 2024;404:145-155. PMID 38772405
- Sun H, et al. IDF Diabetes Atlas: Global, regional and country-level diabetes prevalence estimates for 2021 and projections for 2045. Diabetes Res Clin Pract. 2022;183:109119. PMID 34879977
- Seuring T, et al. The Economic Costs of Type 2 Diabetes: A Global Systematic Review. Pharmacoeconomics. 2015;33:811-831. PMID 25787932
- Anker SD, et al. Empagliflozin in Heart Failure with a Preserved Ejection Fraction. N Engl J Med. 2021;385:1451-1461. PMID 34449189
- Filippatos G, et al. Empagliflozin in HFpEF With and Without Diabetes. Circulation. 2022;146:676-686. PMID 35762322
- Solomon SD, et al. Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction. N Engl J Med. 2022;387:1089-1098. PMID 36027570
- Inzucchi SE, et al. DELIVER outcomes by baseline glycaemic status. Lancet Diabetes Endocrinol. 2022;10:869-881. PMID 36372069
- Bhatt DL, et al. Sotagliflozin in Diabetes and Recent Worsening Heart Failure. N Engl J Med. 2021;384:117-128. PMID 33200892
- Casper J, et al. Comparative Effectiveness of Combination Therapy in Patients with Chronic Kidney Disease and Type 2 Diabetes Using Real-World Data. Nephrol Dial Transplant. 2026. PMID 42658186
- Bhatt DL, et al. Sotagliflozin in Diabetes and Chronic Kidney Disease. N Engl J Med. 2021;384:129-139. PMID 33200891
- Sridhar VS, et al. Sotagliflozin and Kidney Outcomes in SCORED. Clin J Am Soc Nephrol. 2024;19:557-564. PMID 38277468
- Zelniker TA, et al. SGLT2 inhibitors for primary and secondary prevention. Lancet. 2019;393:31-39. PMID 30424892
- Toyama T, et al. SGLT2 inhibitors in type 2 diabetes and CKD. Diabetes Obes Metab. 2019;21:1237-1250. PMID 30697905
- Zhang Y, et al. Finerenone versus SGLT2 inhibitors and GLP-1RAs in T2D and CKD. Cardiovasc Diabetol. 2022;21:232. PMID 36335326
- Neuen BL, et al. GLP-1RA outcomes alone and with SGLT2 inhibitors. Circulation. 2024;150:1781-1790. PMID 39210781