Nutrition and Frailty in the Older Adult: A Case-Based Approach to Assessment, Diagnosis, Intervention, Monitoring, and Evaluation in Preoperative Care

Background/Objectives: Frailty is a multidimensional syndrome characterized by reduced physiologic reserve and increased vulnerability to adverse outcomes, including postoperative complications, functional decline, and mortality. Malnutrition frequently coexists with frailty and contributes to muscle loss, impaired function, and decreased resilience. This narrative review explores the relationship between frailty and malnutrition and highlights practical approaches to assessment and management in older adults undergoing surgery. Methods: A narrative review of the current literature on frailty, malnutrition, comprehensive geriatric assessment, and prehabilitation was conducted. A fictional case study of Mrs. Jones, a 71-year-old woman undergoing evaluation for colon cancer surgery, was used to illustrate evidence-based assessment and management strategies. Results: Frailty and malnutrition interact in a reciprocal cycle that increases surgical risk and worsens health outcomes. Early screening can identify modifiable deficits, including weight loss, inadequate nutritional intake, impaired physical performance, functional limitations, and social barriers. Comprehensive geriatric assessment facilitates evaluation of medical, nutritional, functional, cognitive, and psychosocial factors. Evidence supports multimodal prehabilitation that combines individualized nutrition interventions, adequate protein and energy intake, exercise, medication optimization, oral-health management, and social support to improve surgical readiness and recovery. Conclusions: Routine screening for frailty and malnutrition, followed by comprehensive geriatric assessment and interdisciplinary management, can help identify reversible risk factors and guide individualized care. Integrating nutrition-focused interventions within prehabilitation programs may improve perioperative outcomes while supporting the preservation of strength, function, independence, and quality of life in older adults.