Gillings graduate Engeda finds that new statin guidelines may expose younger adults to greater risk for Type 2 diabetes

October 27, 2020

Dr. Joseph Engeda

Joseph Engeda, PhD, is the lead author of an article recently published in PLOS Medicine about a study that takes a new look at evolving guidelines for the use of statins and calls attention to a need for further research. The article is titled, “Projections of Incident Atherosclerotic Cardiovascular Disease and Incident Type 2 Diabetes across Evolving Statin Treatment Guidelines and Recommendations: A Modelling Study.”

Statin treatment is used to prevent atherosclerotic cardiovascular disease (ASCVD) and works by lowering lipid levels. Though widely prescribed, statins have been associated with increased risk of Type 2 diabetes (T2D). In 2013 and 2018, the American College of Cardiology and American Heart Association updated guidelines related to the use of statins to prevent ASCVD.

Whereas previous guidelines called for statin treatment for patients with elevated levels of low-density lipoprotein cholesterol, updated guidance bases their use on predicted 10-year ASCVD risk, a change which caused an additional 10.4 million adults to become eligible to be prescribed statins. Other recommendations  call for even more widespread use, for example, for those who are predicted to have a 5% chance of developing ASCVD in the next 10 years.

Though previous research has suggested a link between statin treatment to prevent ASCVD and increased rates of T2D, the research team responded to a need for more in-depth exploration of benefits and harms associated with statin treatment among different populations and based on assumed treatment effect.

“We noticed a growing proportion of the population would be eligible for statins for primary prevention even despite an otherwise optimal risk factor profile as the thresholds for statin recommendations were lowered further and further,” said Engeda.

The team conducted simulations based on population study data and determined eligibility for statin treatment under current guidelines by looking at 10-year ASCVD risk. They then calculated the number of people who would have to be treated to prevent one ASCVD event (NNT) and the number needed to harm (NNH) to incur one incident case of T2D and expressed the likelihood to be helped or harmed as a ratio of NNH to NNT. The study examines these results by sex, age and statin-associated T2D relative risk (RR).

The researchers found that statin treatment prevented twice as many ASCVD events as the number of T2D cases it incurred, but that ratio reversed when they assumed higher statin-associated T2D RRs. They also found that females and adults ages 40–50 years received lower benefits compared with males and adults ages 70–75 years. This means that females and younger people assume the highest burden of statin-associated T2D risk.

Findings that new statin guidelines may have negative effects for certain age groups and risk profiles raise questions about other disparate effects. Engeda especially points to the need to investigate the benefits and risks of statin use based on race and ethnicity, suggesting upstream research on these topics, especially in light of disparities in access to health care and medication caused by racism.

“Many knew that COVID-19 would disproportionally impact communities of color and low-income neighborhoods and hopefully now more research and resources will be geared toward targeting root causes of inequities that include, but also extend beyond, the health care system,” said Engeda. “Exploring these determinants could help quantify and address the disparities in COVID-19, too.”

He notes that the COVID-19 pandemic has raised the need for further research to inform statin treatment guidelines because many patients at high risk for COVID-19 are likely eligible for statins. He points out that, though current research is examining if statin use increases chances for survival in COVID-19 patients, more research is needed to understand possible adverse effects.

Engeda received a doctoral degree in epidemiology from the UNC Gillings School of Global Public Health in 2019, an experience he credits with making this consequential research possible.

“The epidemiology department supplied me with the resources, tools, and networks necessary to create and complete this work,” said Engeda. “And of course, my adviser, Dr. Christy Avery, was incredibly important and helpful throughout the entire process.”

Contact the UNC Gillings School of Global Public Health communications team at sphcomm@unc.edu.