2015 AHA/ADA Update on Prevention of Cardiovascular Disease in Adults With Type 2 Diabetes in Light of Recent Evidence

BySteven Lome, MD

Year Released: 2015

Societies: American Heart Association (AHA), American Diabetes Association (ADA)

Summary:

Mortality rates associated with coronary artery disease (CAD) have steadily declined across the United States during the past several decades.

The targeting of certain cardiovascular disease (CVD) risk factors such as lowering smoking prevalence, as well as total cholesterol and blood pressure (BP) levels, has been a driving force in the improvements in CVD outcomes.

However, as these improvements occur in patients with type 2 diabetes, the incremental CVD risks associated with type 2 diabetes persist.

As a result, the AHA and ADA released an update to a joint scientific statement — first published in 1999 and last revised in 2007 — that outlined the best practices to reduce CV risk in adults with type 2 diabetes.

The updated statement includes information from several new clinical trials since 2008 that have changed the clinical practice of CVD risk management in adults with type 2 diabetes.

The panel wrote that its goal in releasing the updated scientific statement was better primary prevention of CVD in all patients with diabetes.

Aspirin therapy

The committee placed recommendations into various classes to help identify the strength of each recommendation. Anything labeled as class I was considered strong, recommended and should be performed or administered. Anything labeled class III had no benefit or the risk outweighs the benefit.

The use of aspirin for the primary prevention of CVD events in patients with diabetes remains controversial, according to the committee. In the general population, aspirin is effective in preventing nonfatal myocardial infarction (MI) in men. However, the evidence for the prevention of nonfatal MI in women is less clear.

After reviewing results from various clinical trials, the committee made two class II recommendations on the use of aspirin for the prevention of CVD in adults with type 2 diabetes.

One recommendation was that low-dose aspirin (75-162 mg per day) is reasonable among those with a 10-year CVD risk of at least 10% and without an increased risk for bleeding.

Lifestyle management

Once an individual is diagnosed with type 2 diabetes, it is important to focus on lifestyle management, according to the committee.

For instance, the committee highlighted results from the Look AHEAD trial. At a minimum, the committee wrote, the study informs clinicians that increased physical activity and improvements in diet can safely lead to weight loss and reduce requirement for medication to control CVD risk factors without a concomitant increase in the risk for CV events.

Additionally, the committee highlighted results from the PREDIMED trial. The trial demonstrated that patients randomly assigned to the Mediterranean diet had a 30% reduced risk for CVD events. The prespecified diabetes subgroup demonstrated similar results, suggesting that a Mediterranean diet may promote CVD risk reduction in patients with diabetes.

Given that individuals with diabetes commonly have elevated triglycerides and reduced high-density lipoprotein (HDL) levels, the committee wrote that it is important to optimize nutrition-related practices, including moderate alcohol intake, substituting healthy fats for saturated and trans fats, limiting added sugars, engaging in regular physical activity and losing excess weight.

Areas of controversy and future research

The committee identified several areas of controversy that require further research. The committee wrote that these areas are important in advancing CVD prevention in type 2 diabetes during the next several years.

Some of the areas of controversy, according to the committee, revolve around antihyperglycemic therapy and bariatric surgery.

The specific role antihyperglycemic therapies have in reducing CV events in type 2 diabetes remains poorly understood, the committee wrote. Additionally, there is still uncertainty whether any specific drug class will emerge as presenting a clear advantage in this regard.

The committee acknowledged that bariatric surgery is an effective treatment for weight loss. However, the committee wrote that long-term follow-up studies in the setting of rigorously designed randomized controlled trials are needed to understand the durability of remission of diabetes and other CVD risk factors.

Updated guidelines address CVD prevention in adults with type 2 diabetes