Mixed dyslipidemia is a condition in which a person has an abnormal combination of lipids (fats) in their blood. It is characterized by high levels of both low-density lipoprotein (LDL) cholesterol and triglycerides, and low levels of high-density lipoprotein (HDL) cholesterol. It is a risk factor for heart disease and stroke. Treatment typically involves lifestyle changes, such as eating a healthy diet and exercising regularly, as well as medications to lower cholesterol and triglyceride levels.