PAI: What the Atherogenic Index Says About Heart Risk

The plasma atherogenic index (PAI) is a number calculated using your triglyceride and HDL (good cholesterol) levels. It shows the balance between fats that can clog your arteries and fats that help protect your heart.

A higher PAI means you may have more small, dense LDL particles—these are more likely to cause heart problems than larger LDL particles. So, PAI helps generate a better understanding of your heart disease risk, especially if your regular cholesterol numbers look normal. A higher PAI also suggests that you are at higher risk of developing metabolic syndrome or diabetes.

The PAI is an important biomarker because it helps contribute to the understanding of your risk for heart disease in a different way than regular cholesterol tests. Even if your cholesterol numbers are normal, the PAI can reveal hidden risks. It looks at the balance between harmful fats (triglycerides) and protective fats (HDL). PAI can be tracked over time to see how your heart health is changing. PAI gives a more accurate picture of your heart health, especially for people with conditions like diabetes, obesity, or high blood pressure. A high PAI may be a sign that action is needed to prevent heart disease.

The reference intervals we use at NiaHealth, initially proposed by Dobiásová in 2001, have been validated in subsequent studies and are generally accepted in the literature (Dobiásová et al., 2011; Dobiásová & Frohlich, 2001; Kammar-García et al., 2020), although some studies have identified >0.24 as an alternate high risk threshold (Dobiásová, 2006; Edwards et al., 2017). A value of less than 0.11 indicates low risk (optimal), a value between 0.11 and 0.21 suggests intermediate risk (at risk), and a value greater than 0.21 indicates high risk (at risk).