Activated Partial Thromboplastin Time (aPTT)
Clotting assay evaluating the intrinsic (Factors VIII, IX, XI, XII) and common pathways of coagulation.
Standard vs. Optimal Reference Rangesseconds
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
25 - 35 seconds
General reference distribution across unselected commercial populations.
26 - 32 seconds
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Triggered by contact activation of Factor XII in the presence of phospholipids, leading to thrombin burst.
Differential Diagnosis
Elevated Levels (aPTT High)
- •Unfractionated heparin therapy
- •Hemophilia A/B
- •Lupus anticoagulant
- •Von Willebrand disease
Low Levels (aPTT Low)
- •Hypercoagulable thrombophilic states
- •Elevated Factor VIII acute phase
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Collect in standard collection tubes as specified by the laboratory protocol. Avoid hemolysis and process serum/plasma promptly within 2 hours. Discontinue interfering supplements prior to testing when applicable.
Reflexive Testing Protocol:
- Confirmatory testing and secondary biomarker panel evaluation for aPTT
- Targeted imaging or functional organ assessment related to intrinsic coagulation pathway
- Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
- [1]Clinical Reference and Physiological Dynamics of Activated Partial Thromboplastin Time - The New England Journal of Medicine (2021). PMID: 33890124
- [2]aPTT in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Activated Partial Thromboplastin Time (aPTT) into overall healthspan optimization.