Modular Organ Aging Framework in the Real World: Cost, Frequency, Equity, and a Patient-Facing Calculator

Abstract

Chronological age reflects time since birth, whereas biological ageing captures heterogeneous decline across cells, tissues, and organs. Composite biological age integrates biomarkers across organ systems, yet a feasibility-first pathway to translate organ-age theory into real-world monitoring and communication remains lacking. We present an implementation-oriented toolkit that classifies candidate biomarkers across cardiovascular, neurologic, pulmonary, renal, hepatic, musculoskeletal, immune, endocrine, and integumentary domains into functional ageing tests (e.g., grip strength, gait speed, reaction time, sleep architecture) and physiological markers (e.g., MRI-based brain volume, IGF-1, cystatin C). To enhance interpretability, we introduce a fast- versus slow-ageing organ framework based on deviations from age-referenced norms. Crucially, all measures are organized into feasibility tiers: Tier 0 (low-cost, at-home tests), Tier 1 (routine, low-cost laboratory tests), Tier 2 (specialist-administered assessments), and Tier 3 (send-out or referral laboratory tests). We summarize accessibility, cost, recommended testing intervals, expected biological drift to reduce over-interpretation, and population-specific reference ranges. The proposed application enables individuals to input routine laboratory and functional data to visualize organ-specific trajectories and composite biological age for self-tracking and research purposes only, supported by human factors such as clear design principles and explicit clinical disclaimers.

Keywords: Biological Age, Aging Biomarkers, Organ-specific Aging, Epigenetic Clocks

DOI: 10.54941/ahfe1007468