ADA Diabetes Guidelines 2015–2019: Major Changes in Diabetes Care

ADA Diabetes Guidelines 2015–2019: Historical Timeline

The timeline below combines developments in the annual ADA Standards, separate ADA/EASD statements and major clinical research. A trial published during a particular year may have influenced later recommendations rather than that year's January Standards.

ADA Diabetes Guidelines 2015: Updating Patient-Centered Treatment

In 2015, the ADA Standards continued emphasizing diagnosis, glycemic management, nutrition, exercise, cardiovascular risk reduction and the prevention of diabetes complications.

That year also brought an important separate publication: the ADA/EASD update to its 2012 patient-centered position statement on treating hyperglycemia in type 2 diabetes.

What did the 2015 ADA/EASD update address?

The joint publication reviewed available therapies and discussed how treatment choices could reflect individual needs.

• Metformin as a usual initial medication when appropriate.
• Available oral and injectable glucose-lowering therapies.
• Hypoglycemia risk and treatment-related weight changes.
• Medication tolerability and adverse effects.
• Patient preferences and practical treatment burden.
• The need to intensify treatment when glycemic goals were not achieved.

The update reflected a broadening therapeutic landscape, but definitive cardiovascular outcome evidence for several medication classes was still emerging.

Historical distinction: The ADA/EASD position statement was not the same document as the 2015 annual ADA Standards.

Source: ADA/EASD 2015 Position Statement.

ADA Diabetes Guidelines 2016: Cardiovascular Outcomes Become More Important

The 2016 ADA Standards continued to provide comprehensive diabetes recommendations covering diagnosis, treatment goals, cardiovascular risks and chronic complications.

An important development was the growing clinical relevance of cardiovascular outcome studies required or conducted for newer glucose-lowering medications.

The EMPA-REG OUTCOME findings

Results from the EMPA-REG OUTCOME trial were published in 2015 and became particularly influential during the following years.

The study enrolled adults with type 2 diabetes and established cardiovascular disease and evaluated empagliflozin, an SGLT2 inhibitor, against placebo in addition to standard care.

The trial found reductions in its primary composite cardiovascular outcome and in cardiovascular death in the population studied.

These findings were important because they demonstrated that a glucose-lowering medication could provide clinically meaningful cardiovascular benefits in a defined patient group.

The findings were not proof that every SGLT2 inhibitor produced identical cardiovascular benefits in every person with diabetes. Evidence was drug-specific and population-specific.

ADA Diabetes Guidelines 2017: Cardiovascular and Kidney Outcomes

In 2017, ADA guidance continued addressing the relationship between glucose control, cardiovascular disease and kidney complications.

Clinical evidence continued evolving, including results involving different SGLT2 inhibitors and GLP-1 receptor agonists.

Liraglutide and the LEADER trial

The LEADER trial, published in 2016, found that liraglutide reduced its primary composite cardiovascular outcome compared with placebo among adults with type 2 diabetes at high cardiovascular risk.

It provided important evidence for a GLP-1 receptor agonist and contributed to later guideline discussions.

Canagliflozin and the CANVAS Program

In 2017, the CANVAS Program reported cardiovascular benefit with canagliflozin in a population with type 2 diabetes and elevated cardiovascular risk.

However, the trials also identified important safety concerns, including an increased risk of lower-limb amputations in the studied population.

This underlined the need to weigh benefits and harms rather than treating medication classes as interchangeable.

These findings helped inform subsequent ADA Standards and consensus recommendations. Not every result published in 2017 would have been incorporated into the January 2017 Standards.

ADA Diabetes Guidelines 2018: A New ADA/EASD Consensus Report

One of the defining documents of this historical period was the 2018 ADA/EASD consensus report on the management of hyperglycemia in type 2 diabetes.

The report placed greater emphasis on selecting glucose-lowering treatments according to comorbidities and patient priorities.

Key developments in the 2018 consensus

• Continued emphasis on lifestyle management and diabetes self-management education.
• Greater attention to obesity and weight management.
• Medication choices informed by established atherosclerotic cardiovascular disease.
• Consideration of heart failure and chronic kidney disease when selecting therapies.
• Recognition of proven cardiovascular benefits for certain SGLT2 inhibitors and GLP-1 receptor agonists.
• For many patients requiring injectable therapy, consideration of a GLP-1 receptor agonist before insulin, except when clinical circumstances called for insulin.
• Attention to medication costs, hypoglycemia and patient preferences.

This represented a significant evolution from earlier algorithms that placed greater emphasis on stepwise escalation according to A1C.

Original source: ADA/EASD 2018 Consensus Report.

ADA Diabetes Guidelines 2019: Treatment Beyond A1C

The 2019 ADA Standards reflected an expanding evidence base regarding cardiovascular and kidney outcomes in type 2 diabetes.

For selected patients with established atherosclerotic cardiovascular disease, heart failure or chronic kidney disease, medication choice increasingly involved evidence beyond glucose reduction.

Important treatment considerations included:

• Established cardiovascular disease and cardiovascular outcome evidence.
• Heart failure and risk of hospitalization.
• Chronic kidney disease and kidney function.
• Hypoglycemia risk.
• Body weight and treatment tolerability.
• Financial access and patient preferences.

Not all people with type 2 diabetes required the same treatment strategy. Medication selection needed to account for the individual clinical situation and the evidence available for particular therapies.

A further ADA/EASD update appeared at the end of 2019

The authors of the 2018 ADA/EASD consensus published an update online in December 2019 in response to new cardiovascular outcome evidence.

That update was subsequently published in the February 2020 issue of Diabetes Care.

Therefore, it is historically correct to describe it as a 2019 online update published in a 2020 journal issue, rather than calling it the January 2019 annual ADA Standards.

The update further clarified the role of certain SGLT2 inhibitors and GLP-1 receptor agonists in patients with cardiovascular or kidney risk, including situations where decisions about organ protection should not depend solely on baseline A1C.

Source: 2019 ADA/EASD Consensus Update.

Major Diabetes Cardiovascular Outcome Trials, 2015–2019

Several influential studies contributed to changing diabetes treatment recommendations during this period.

These trials enrolled different populations and evaluated different outcomes. Their results should not be interpreted as showing identical benefits for every medicine or every person with diabetes.

What Changed in Diabetes Treatment Between 2015 and 2019?

1. Cardiovascular outcomes became a treatment priority

Clinical decisions increasingly incorporated evidence that certain glucose-lowering medicines could improve important cardiovascular outcomes in selected patients.

2. Kidney protection became more prominent

Evidence from cardiovascular and dedicated kidney outcome trials increased attention to kidney disease when choosing diabetes medications.

3. Heart failure influenced medication selection

Evidence regarding heart failure hospitalization helped differentiate treatment options for people with particular cardiovascular conditions.

4. Weight management remained central

The 2018 ADA/EASD consensus emphasized weight management through lifestyle interventions, medication and, for appropriate patients, metabolic surgery.

5. Medication benefits and risks required individual assessment

The trials reinforced the importance of matching medication selection to patient characteristics, rather than assuming that one drug class was always the best choice.

How 2015–2019 Diabetes Care Compares With Modern Guidelines

The 2015–2019 period helped establish important principles that still influence diabetes care.

However, clinical trials, approved treatments and recommendations have developed further since 2019.

• Cardiovascular care: Later evidence refined treatment selection for people with different cardiovascular risk profiles.
• Kidney disease: Additional studies expanded the evidence base for kidney-protective treatment strategies.
• Obesity management: More therapeutic options became available in subsequent years.
• Diabetes technology: Continuous glucose monitoring and automated insulin delivery developed substantially.
• Individualization: Current recommendations integrate multiple clinical outcomes, comorbidities and patient goals.

Medical information notice: This independently authored article is intended for historical education. It is not an official publication of the American Diabetes Association or the European Association for the Study of Diabetes. Do not use historical treatment recommendations instead of current clinical guidance.