Glossary of Terms

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Acute Myocardial Infarction
The medical term for “heart attack.” Acute myocardial infarction results from a blockage in one or more of the blood vessels leading to the heart. Damage to the heart muscle results, due to the lack of blood flow. Abbreviation: AMI.

Automated External Defibrillator

The age-adjusted percentage is an artificial estimate that minimizes the effects of different age distributions and allows comparisons between different populations. It represents what the crude percentage would have been in the study population if that population had the same age distribution as a standard population. For example, that is a population in which the age composition is known precisely as a result of a census.

Acute Myocardial Infarction

Angina is chest pain or discomfort that occurs if an area of your heart muscle doesn’t get enough oxygen-rich blood. Angina isn’t a disease; it’s a symptom of an underlying heart problem. Angina usually is a symptom of coronary heart disease (CHD).

An anticoagulant is a medication that helps prevent blood clotting. They can prevent new clots from forming or an existing clot from enlarging. They do not dissolve existing clots. Heparin and warfarin are examples of anticoagulants.

An antiplatelet is a medication that decreases platelet aggregation and inhibits thrombus formation. They are effective in the arterial circulation, where anticoagulants have little effect. They are widely used in primary and secondary prevention of thrombotic cerebrovascular or cardiovascular disease. Aspirin and Prasugrel are examples of antiplatelets.

An antithrombotic is a drug that reduces the formation of blood clots. Antithrombotics can be used therapeutically for prevention (primary prevention, secondary prevention) or treatment of a dangerous blood clot (acute thrombus). Different antithrombotics affect different blood clotting processes: Antiplatelet drugs limit the migration or aggregation of platelets; Anticoagulants limit the ability of the blood to clot; Thrombolytic drugs act to dissolve clots after they have formed.

Atherosclerosis is a disease in which plaque builds up inside your arteries. Arteries are blood vessels that carry oxygen-rich blood to your heart and other parts of your body. Atherosclerosis can lead to serious problems, including heart attack, stroke, or even death.


Blood Pressure (BP)
Blood Pressure is the force of blood on the inside walls of blood vessels, measured by analyzing both the systolic blood pressure, the pressure when the heart pushes blood out into the arteries (systole), and the diastolic blood pressure, when the heart is at rest (diastole). Blood pressure is measured in millimeters of mercury (mmHg) and is commonly recorded as systolic/diastolic pressure; for example, blood pressure at or above 140/90 mmHg is considered high, or hypertensive.

Blood Lipids
Fat in the blood stream, which is measured with a lipid profile blood test. The lipid profile test measures total cholesterol, the fat produced by the liver and found in some foods; triglycerides, the storage form of fat in the body; High-density Lipoprotein (HDL) cholesterol, fat that takes extra cholesterol from the blood to the liver for removal; and Low-density Lipoprotein (LDL) cholesterol, fat that takes excess cholesterol around the body to where it’s needed, but excess ultimately rests on the inside of artery walls.

Body Mass Index (BMI)
Weight in kilograms divided by the height in meters squared (BMI = [weight(kg)/height(m)2]); a standard measure for the purpose of determining overweight or obesity.

Behavioral Risk Factor Surveillance System.


C-Reactive Protein
C-reactive protein is an antibody found in the blood in certain acute and chronic conditions including infections and cancers. It is a nonspecific indicator of inflammation and, therefore, not diagnostic of any one disease.

Coronary artery bypass grafting (CABG) is a type of surgery that improves blood flow to the heart. Surgeons use CABG to treat people who have severe coronary heart disease (CHD). During CABG, a healthy artery or vein from the body is connected, or grafted, to the blocked coronary artery.

Cardiovascular Diseases
Diseases relating to the heart and the blood vessels or the circulation.

Cardiac Arrest Registry to Enhance Survival

Coronary heart disease (CHD) is a disease in which a waxy substance called plaque builds up inside the coronary arteries. These arteries supply oxygen-rich blood to your heart muscle. If the flow of oxygen-rich blood to your heart muscle is reduced or blocked, angina or a heart attack can occur.

The most abundant steroid in animal tissues, especially in bile and gallstones, and present in food, especially food rich in animal fats; cholesterol circulates in the plasma complexed to proteins of various densities and plays an important role in the pathogenesis of atheroma formation in arteries.

Confidence Interval (CI)
Conventional form of an interval estimate, computed in statistical analyses, based on the theory of frequency probability.

Existing at birth, referring to certain mental or physical traits, anomalies, malformations, diseases, and like findings, which may be either hereditary or due to an influence occurring during gestation up to the moment of birth.

Coronary Heart Disease
Disease caused by a lack of blood to the heart due to a narrowing or obstruction of the arteries that could result in a heart attack. Also called Ischemic Heart Disease.

Paul Coverdell National Acute Stroke Program

Cardiopulmonary resuscitation, commonly known as CPR, is an emergency procedure performed in an effort to manually preserve intact brain function until further measures are taken to restore spontaneous blood circulation and breathing in a person who is in cardiac arrest.

C-Reactive Protein

The crude percentage is the raw percentage or the unadjusted estimate.

CAT Scan (Computed Axial Tomography). Cardiac computed tomography, or cardiac CT, is a painless test that uses an x-ray machine to take clear, detailed pictures of the heart. Doctors use this test to look for heart problems. Different types of CT scans are used for different purposes. For example, multidetector computed tomography (MDCT) is a fast type of CT scanner. Because the heart is in motion, a fast scanner is able to produce high-quality pictures of the heart. MDCT also might be used to detect calcium in the coronary arteries. Another type of CT scanner, called electron-beam computed tomography (EBCT), also is used to detect calcium in the coronary arteries.

Cardiovascular Disease

Cardiovascular Health


Diabetes Mellitus is a chronic metabolic disorder in which the use of carbohydrate is impaired and that of lipid and protein is enhanced. It is caused by an absolute or relative deficiency of insulin and is characterized, in more severe cases, by chronic hyperglycemia, glycosuria, water and electrolyte loss, ketoacidosis, and coma. Long-term complications include neuropathy, retinopathy, nephropathy, generalized degenerative changes in large and small blood vessels, and increased susceptibility to infection.

Deep Vein Thrombosis (DVT) is a blood clot that forms in a vein deep in the body. Blood clots occur when blood thickens and clumps together.

Dyslipidemia is an abnormal amount of lipids (e.g. cholesterol and/or fat) in the blood. This can include high levels of serum total or Low-density Lipoprotein (LDL) cholesterol, high levels of triglycerides, or low levels of High-density Lipoprotein (HDL) cholesterol.

Dysphagia is difficulty swallowing due to dysfunction of the muscle required to swallow, and can be a resulting complication from a stroke.


An echocardiogram (also called an echo) is a type of ultrasound test that uses high-pitched sound waves that are sent through a device called a transducer. The device picks up echoes of the sound waves as they bounce off the different parts of your heart. These echoes are turned into moving pictures of your heart that can be seen on a video screen. Echocardiogram investigation of the heart and great vessels can be used to identify cardiovascular lesions.

Electrocardiogram (EKG or ECG)
An electrocardiogram, also called an EKG or ECG, is a simple, painless test that records the heart’s electrical activity. Doctors use EKGs to detect and study many heart problems, such as heart attacks, arrhythmias, and heart failure.


Common abbreviation for Fasting Plasma Glucose.


Glucose measurements, usually from fasting plasma, are used in the diagnosis and treatment of carbohydrate metabolism disorders. Diabetes causes elevated levels of glucose to circulate in the blood.

Glycohemoglobin (or glycated hemoglobin: HbA1c)
Although fasting blood glucose measures the glucose status for the previous twelve hours, the stable HbA1c is measured primarily to identify the average plasma glucose concentration over prolonged periods. Glycohemoglobin is measured and recorded in percentages; for example, glycohemoglobin >=6.5% is considered high.


Abbreviation for Glycohemoglobin (or glycated hemoglobin).

Healthcare Cost and Utilization Project

Heart Disease

High-density Lipoprotein
The high density lipoproteins transport cholesterol from the tissues of the body to the liver so it can be eliminated in the bile. HDL cholesterol (HDL-c) is considered the “good” cholesterol.

Heart Disease and Stroke Prevention

Heart Attack
The common name for Acute Myocardial Infarction. A heart attack happens when the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart can’t get oxygen. If blood flow isn’t restored quickly, the section of heart muscle begins to die. Heart attacks most often occur as a result of coronary heart disease (CHD), also called coronary artery disease.

Heart Failure
A progressive condition where the heart muscle weakens and cannot pump blood efficiently. Fluid accumulates in the lungs, hands, ankles, or other parts of the body.

Hemorrhagic Stroke
Stroke caused by the bleeding of ruptured blood vessels (hemorrhage) in the brain.

Heart Failure

Homocysteine is an amino acid in the blood. Epidemiological studies have shown that too much homocysteine in the blood (plasma) is related to a higher risk of coronary heart disease, stroke and peripheral vascular disease.

High blood pressure; transitory or sustained elevation of systemic arterial blood pressure to a level likely to induce cardiovascular damage or other adverse consequences.


Ischemic Heart Disease

The number of new events (e.g. death or a particular disease) occurring during a specified period of time in a population at risk of developing the events.

Ischemic Heart Disease
Disease caused by a lack of blood to the heart due to a narrowing or obstruction of the arteries that could result in a heart attack.

Ischemic Stroke
Stroke caused by blockage in a blood vessel, leading to no blood to the brain tissues distal to the blockage.




Low-density lipoprotein
Low-density lipoprotein (LDL) transports cholesterol from the liver to the tissues of the body. LDL cholesterol (LDL-c) is considered the “bad” cholesterol.


The mean is one measure of the central tendency either of a probability distribution or of the random variable characterized by that distribution and equals the sum of observations divided by the number of observations.

The median is one measure of central tendency of a probability distribution. The median is the number separating the higher half of a data sample, a population, or a probability distribution, from the lower half. The median equals the observation in the center when all observations are ordered from smallest to largest; when there is an even number of observations, the median equals the average of the middle two values.

Myocardial Infarction

Magnetic Resonance Imaging


National Ambulatory Medical Care Survey

Natural Breaks
The Natural Breaks classing method identifies groupings that naturally exist in the data. The classes or “breaks” (i.e., categories or intervals) are selected using a statistical process that determines the “break points” where there are relatively big jumps in the data values to best group similar values and to maximize the differences between classes.

National Hospital Ambulatory Medical Care Survey

National Health and Nutrition Examination Survey

National Health Interview Survey

Nationwide Inpatient Sample (from the Healthcare Cost and Utilization Project or HCUP)


Out-of-Hospital Cardiac Arrest

A Body Mass Index (BMI) between 25.0-29.9

Obese (Obesity)
A Body Mass Index (BMI) >=30.0


Peripheral Arterial Disease

Percutaneous Coronary Intervention

Paul Coverdell National Acute Stroke Program

A percentile (or a centile) is a measure used in statistics indicating the value below which a given percentage of observations in a group of observations fall. For example, the 20th percentile is the value (or score) below which 20 percent of the observations may be found.

Peripheral Artery Disease
Narrowing of the arteries of the legs caused by plaque prevalence.

A measure of the commonness of a disease or condition. The prevalence represents the total number of individuals who have a disease at a particular time (or period) divided by the population at risk of having the disease, multiplied by 100 to convert to a percentage.


Cut-points dividing a set of observations into equal sized groups (equal number of observations); for example, quartiles divide observations into 4 equal sized groups and quintiles divide observations into 5 equal sized groups.


The rate is the number of events that occur over the sum of time individuals in the population were at risk for the event. For example, the mortality rate is usually expressed as the rate per 100,000 population, which equals the number of deaths divided by the total population, divided by 100,000 [Rate = #deaths/(#population/100,000)].


Sentinel Surveillance
Sentinel Surveillance is based on selected population samples chosen to represent the relevant experience of particular groups, often from specific geographic locations.

Standard Deviation (SD)
The standard deviation (SD) is a measure that is used to quantify the amount of variation or dispersion of a set of data values. The SD of a random variable, statistical population, data set, or probability distribution is the square root of its variance. In a normal distribution, approximately 68% of observations will be within 1 SD of the mean of the distribution, and about 95% will be within 2 SDs.

Standard Error (SE)
The standard error (SE) is the standard deviation of the sampling distribution of a statistic, most commonly of the mean. The standard error of the mean (SEM) is the standard deviation of the sample-mean’s estimate of a population mean. It can also be viewed as the standard deviation of the error in the sample mean with respect to the true mean, since the sample mean is an unbiased estimator. SEM is usually calculated as the sample estimate of the population standard deviation (sample SD) divided by the square root of the sample size.

A stroke is any acute clinical event, related to the impairment of cerebral circulation that lasts longer than 24 hours. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Ischemic is the more common type of stroke.


Thrombolysis is the breakdown (lysis) of blood clots by pharmacological means. It works by stimulating secondary fibrinolysis by plasmin through infusion of analogs of tissue plasminogen activator (tPA), the protein that normally activates plasmin.

Transient Ischemic Attack

Tissue Plasminogen Activator (t-PA or tPA)
t-PA is a protein involved in the breakdown of blood clots. t-PA is used in some cases of diseases that feature blood clots, such as pulmonary embolism, myocardial infarction, and stroke, in a medical treatment called thrombolysis. The most common use is for ischemic stroke.

t-PA (or tPA)
Tissue Plasminogen Activator

Transient Ischemic Attack (TIA)
A transient ischemic attack or TIA is a condition that is similar to a stroke; A TIA occurs if blood flow to a portion of the brain is blocked only for a short time. Thus, damage to the brain cells isn’t permanent (lasting).



Venous Thromboembolism
A venous thrombus is a blood clot (thrombus) that forms within a vein. When a blood clot breaks loose and travels in the blood, this is called a venous thromboembolism (VTE). Medications used to treat this condition include anticoagulants such as heparin and warfarin.

Venous thromboembolism

Vital Records
Certificates of birth, death, marriage, and divorce required for legal and demographic purposes.






Everitt, B.S. (2003) The Cambridge Dictionary of Statistics, CUP. ISBN 0-521-81099-X

Dodge, Yadolah (2003). The Oxford Dictionary of Statistical Terms. Oxford University Press. ISBN 0-19-920613-9.

Porta, M, Greenland S, Last JM, editors. A dictionary of epidemiology. New York: Oxford University Press, 2008

MedPage Tools. Guide to Biostatistics. Available at:[PDF-380K]External

Stedman’s Medical Dictionary, 28th Edition. Lippincott Williams & Wilkins, 2006.

National Institutes of Health (NIH), National Heart, Lung, and Blood Institute (NHLBI), Health Topics. Available at:

National Health and Nutrition Examination Survey (NHANES) Laboratory Methods. Available at: