Malnutrition—a broad term for the inadequate consumption and utilization of nutrients necessary for bodily functioning, which leads to impaired body composition as well as physical and mental function—is common in older adults.1 According to a 2025 comprehensive systematic review and meta-analysis, the estimated prevalence of malnutrition in this population is 20.3% in the United States.2 There are multiple factors linked to the increased risk, including physiological changes, accumulation of comorbidities, and limited access to nutritious food.3 Malnutrition in older adults results in special considerations for perioperative care due to patients’ altered physiologic and metabolic profiles.
Perioperative malnutrition is an independent risk factor for poor post-operative outcomes.4 In a 2025 retrospective cohort study, increasing severity of malnutrition was found to be significantly associated with increased risk of post-operative complications among geriatric patients undergoing spinal surgery.5 In this study, both malnourished and severely malnourished cohorts were found to have statistically significant increased proportions of adverse events (p <0.001), longer lengths of stay (p <0.001), and increased 30-day mortality (p <0.001) using multivariable analysis.5
Not all surgeries confer the same risk of malnutrition. A 2021 retrospective analysis yielded data demonstrating that upper gastrointestinal tract surgery (odds ratio [OR] 20.4, p <0.001), hepatobiliary-pancreatic surgery (OR 3.7, p = 0.001), and lower gastrointestinal surgery (OR 5.2, p < 0.001) were variables independently associated with malnutrition risk among the elderly (defined as an age >65 years).6
Given the profound associations between malnutrition in older adults and poorer outcomes in the perioperative period, an initial assessment of risk for malnutrition may be helpful in guiding care and instituting preventive efforts. The Malnutrition Universal Screening Tool (MUST) is a clinical risk appraisal for malnutrition and has been shown to be highly accurate in detecting malnutrition risk for hospitalized patients.7 In a 2024 validation systematic review and meta-analysis, the MUST risk calculator was compared to the reference standards, the Subjective Global Assessment (SGA) and the European Society for Clinical Nutrition and Metabolism (ESPEN). Compared to the SGA, the MUST had a sensitivity of 0.84 (95% confidence interval [CI] 0.73-0.91) with a specificity of 0.85 (95% CI 0.75-0.91). Meanwhile, compared to the ESPEN, MUST demonstrated a sensitivity of 0.97 (95% CI 0.53-0.99) and a specificity of 0.80 (95% CI 0.50-0.94).7
For those deemed higher risk for pre-operative malnutrition, it is recommended that a holistic and patient-centered approach is taken to lower the risk of associated post-operative complications.8 Specifically, this may entail involving nutritional rehabilitation services to optimize nutrition through the use of supplementary nutrition (e.g., vitamin D, protein, carbohydrate loading) as well as ensuring adequate peri-operative hydration.8
Older adults are at higher risk of malnutrition, which confers higher risk of several adverse post-operative outcomes. The MUST screening tool is a helpful risk calculator for identifying those at increased risk of malnutrition, enabling the incorporation of nutritional rehabilitation prior to surgery, which can optimize the patient’s nutritional status and mitigate the risks associated with perioperative malnutrition. However, minimizing this risk relies upon multi-disciplinary collaboration with all medical teams to identify and allocate resources to attenuating risk in the perioperatively malnourished elderly patient.
References
1. Cruz-Jentoft AJ, Volkert D. Malnutrition in Older Adults. N Engl J Med. 2025;392(22):2244-2255. doi:10.1056/NEJMra2412275
2. Salari N, Darvishi N, Bartina Y, Keshavarzi F, Hosseinian-Far M, Mohammadi M. Global prevalence of malnutrition in older adults: A comprehensive systematic review and meta-analysis. Public Health Pract. 2025;9:100583. doi:10.1016/j.puhip.2025.100583
3. Dent E, Wright ORL, Woo J, Hoogendijk EO. Malnutrition in older adults. The Lancet. 2023;401(10380):951-966. doi:10.1016/S0140-6736(22)02612-5
4. Williams DGA, Molinger J, Wischmeyer PE. The malnourished surgery patient: a silent epidemic in perioperative outcomes? Curr Opin Anaesthesiol. 2019;32(3):405-411. doi:10.1097/ACO.0000000000000722
5. Elsamadicy AA, Serrato P, Belkasim S, et al. Impact of preoperative nutritional status on morbidity and mortality in geriatric patients undergoing spine surgery: Role of geriatric nutritional risk index. Clin Neurol Neurosurg. 2025;256:109000. doi:10.1016/j.clineuro.2025.109000
6. Venianaki M, Andreou A, Nikolouzakis TK, Chrysos E, Chalkiadakis G, Lasithiotakis K. Factors Associated with Malnutrition and Its Impact on Postoperative Outcomes in Older Patients. J Clin Med. 2021;10(12):2550. doi:10.3390/jcm10122550
7. Cortés-Aguilar R, Malih N, Abbate M, Fresneda S, Yañez A, Bennasar-Veny M. Validity of nutrition screening tools for risk of malnutrition among hospitalized adult patients: A systematic review and meta-analysis. Clin Nutr Edinb Scotl. 2024;43(5):1094-1116. doi:10.1016/j.clnu.2024.03.008
8. Gumuskaya O, Skendri S, Birkenhead K, Sarkies MN. Perioperative nutrition in older patients: what are the priorities? Curr Opin Clin Nutr Metab Care. 2025;28(1):6-13. doi:10.1097/MCO.0000000000001085
