Glossary

Longevity Clinic Glossary

Alphabetical definitions for commonly used biomarker and testing terms.

Apolipoprotein B (ApoB)

Blood test counting atherogenic cholesterol particles. Higher ApoB suggests more plaque-forming lipoprotein burden.

Basophils

Least common white blood cell type involved in allergic and inflammatory signaling; often variable and low-volume in routine CBC interpretation.

Bilirubin (Direct)

Conjugated bilirubin processed by the liver; elevations can indicate hepatic or biliary dysfunction and are interpreted with liver enzymes.

Blood Pressure

Core vital sign measuring pressure in arteries. Persistent elevation is a major cardiovascular risk signal.

Body Composition (DXA)

Dual-energy X-ray assessment of fat, lean mass, and bone composition used for metabolic and frailty risk tracking.

Bone Density (DXA)

DXA-based bone mineral density test used to detect osteopenia and osteoporosis risk.

Calcium (Serum)

Regulated electrolyte tied to bone, muscle, and endocrine health; interpreted with albumin and vitamin D context.

Cardiac Stress Test

Exercise or pharmacologic test evaluating perfusion and ischemic signs not always visible at rest.

Carotid Intima-Media Thickness (CIMT)

Ultrasound measurement of carotid wall thickness used to estimate early atherosclerotic burden.

Cognitive Screening

Structured memory and executive-function testing used to detect early decline before overt dementia syndromes.

Comprehensive Metabolic Panel (CMP)

Multi-analyte chemistry panel covering glucose, electrolytes, kidney markers, and liver enzymes for broad metabolic screening.

Coronary Calcium Scan

CT-based scoring of calcified coronary plaque to estimate atherosclerotic cardiovascular risk.

Creatinine

Renal filtration marker derived from muscle metabolism; evaluated with urea and eGFR for kidney-aging context.

DNA Methylation Clocks

Epigenetic assays estimating biological age from DNA methylation signatures across selected genomic loci.

Electrocardiogram (ECG/EKG)

Heart electrical activity recording used for rhythm abnormalities and prior injury patterns.

Gamma-Glutamyl Transferase (GGT)

Liver enzyme linked to glutathione metabolism, oxidative stress, and metabolic-liver burden.

Gamma-Globulins

Immunoglobulin fraction of serum proteins; elevations may track chronic immune activation and inflammaging patterns.

Grip Strength

Dynamometer measure of hand strength used as a fast frailty and functional reserve indicator.

Hemoglobin

Oxygen-carrying red-cell protein. Age-related decline and anemia patterns can reflect nutritional and inflammatory load.

Hemoglobin A1c (HbA1c)

Three-month blood glucose exposure marker used for diabetes and insulin-resistance risk assessment.

High-sensitivity C-reactive Protein (hs-CRP)

Low-level systemic inflammation marker associated with cardiometabolic and vascular risk.

Lipid Panel

Measures LDL, HDL, triglycerides, and cholesterol distribution to assess atherosclerotic risk.

Lipoprotein(a) [Lp(a)]

Inherited lipoprotein marker associated with earlier and more aggressive vascular plaque risk.

MCHC (Mean Corpuscular Hemoglobin Concentration)

Average hemoglobin concentration inside red blood cells; used in anemia pattern classification.

MCV (Mean Corpuscular Volume)

Average red blood cell size; helps identify microcytic or macrocytic anemia patterns.

Monocytes

Myeloid immune cells that can increase with chronic low-grade inflammation and immune aging.

Neutrophils

Frontline innate immune cells; counts may stay stable with age while functionality often declines.

Platelets

Clotting cell fragments that also participate in inflammatory signaling and vascular biology.

Pulse Oximetry

Noninvasive oxygen saturation measurement used to monitor cardiopulmonary oxygen delivery.

Pulse Wave Velocity

Arterial stiffness metric based on pulse transit speed; higher values suggest vascular aging.

Resting Metabolic Rate (RMR)

Baseline calorie expenditure at rest; helps profile metabolic efficiency and adaptation.

Sodium

Primary extracellular electrolyte essential for fluid and neurologic balance; vulnerable to dysregulation in older adults.

Spirometry

Breathing function test (FEV1/FVC) for airflow limitation and respiratory reserve.

Telomere Length

Measurement of chromosomal end-cap length, sometimes used as an exploratory cellular-aging signal.

Total Protein

Combined albumin and globulin concentration indicating nutritional, hepatic, and inflammatory state.

VO2 Max

Maximal oxygen uptake during exercise, commonly used as a cardiorespiratory fitness and longevity proxy.

Whole-Genome Sequencing

Broad DNA sequencing that can reveal inherited variants tied to disease susceptibility and prevention planning.