Heterogeneity as the cornerstone for tailoring geriatric and gerontological interventions

Heterogeneity is a fundamental characteristic of the aging population and should be central to patient-centered geriatric and gerontological care.The variability amassed over the life course renders older adults the most physiologically diverse demographic, significantly impacting their health trajectories, functional capacity, cognitive function, emotional well-being, and social circumstances.This review proposes a multidimensional framework that recognizes each older adult as a unique mixture of biological, functional, psychological, and social conditions.We describe five major determinants of variability: biological/ genetic factors, cognitive and psychological factors, functional capacity and lifestyle, chronic diseases and multimorbidity, and social and environmental influences, and highlight their relevance in clinical decision-making.These dimensions shape therapeutic tolerance, clinical outcomes, and the ability to benefit from guideline-based care, underscoring the importance of comprehensive and individualized assessment.The Comprehensive Geriatric Assessment serves as a clinical framework for addressing the heterogeneity of the geriatric population by integrating key dimensions of health, including cognitive function, physical performance, frailty, nutritional status, emotional well-being, sleep quality, and social support.It particularly highlights cognitive frailty, a potentially reversible state combining physical frailty and cognitive impairment for which multidomain interventions, such as the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability method, have shown promise.This narrative review aims to recognize the inherent variability in geriatrics, enabling clinicians to develop patient-centered, multimodal interventions that account for both biological age and individual circumstances.