Missed opportunities in nutritional care: prevalence, mortality, and resource utilization in internal medicine wards

Background Malnutrition is a highly prevalent and underdiagnosed condition among hospitalized patients, especially in internal medicine wards. Hospital malnutrition is associated with increased morbidity, mortality, prolonged admissions, and a substantial economic burden. Objectives This study aimed to assess the clinical and economic impact of nutritional risk in patients admitted to internal medicine wards, focusing on mortality, hospital resource utilization, and the effectiveness of nutritional interventions. Methods A retrospective cohort study was conducted at ULS Santo António, Porto, including 1,150 hospital admissions from January to December 2022. All adult patients with nutritional risk screening (NRS-2002) in the first 48 h of admission were included. Data were collected from hospital information systems on demographic, clinical, and economic variables, with outcomes including in-hospital mortality, readmissions at 30, 90, and 180 days, and one-year post-discharge mortality. Results Nutritional risk (NRS-2002 ≥ 3) was identified in 42.4% of patients ( n  = 488), while ICD-10 malnutrition coding at discharge was recorded in only 0.7% of admissions. Of patients at nutritional risk, 74.4% ( n  = 363) received no nutritional supplementation. Nutritional risk was associated with higher in-hospital mortality, longer length of stay, and increased costs across all resource categories. In the time-dependent Cox model, patients at nutritional risk without supplementation showed a markedly higher hazard of in-hospital death at admission (HR 23.32, 95% CI 13.09–41.56), with this excess hazard attenuating over time. Patients at nutritional risk who received supplementation also showed elevated early risk (HR 6.15, 95% CI 2.96–12.80), though lower than unsupplemented patients. A similar pattern was observed for one-year post-discharge mortality. Total hospitalization costs were approximately 79% higher in at-risk patients, driven mainly by longer length of stay. Conclusion Nutritional risk affected 42.4% of internal medicine inpatients and was associated with higher mortality and resource use. The finding that 74.4% of at-risk patients received no nutritional intervention represents a substantial missed opportunity. Patients who received nutritional supplementation showed a pattern of lower mortality risk than unsupplemented at-risk patients, consistent with but not proving a beneficial association. These findings support systematic nutritional screening and timely intervention in hospital care.