Antibiotics | Preserving Health Beyond Infection Control: Frailty, Weight, and Cognition in OPAT Patients

This study systematically evaluated the impact of Outpatient Parenteral Antibiotic Therapy (OPAT) on patients' frailty status, weight, and cognitive function, expanding the health-protective role of OPAT beyond infection control. The study employed a multicenter retrospective design, including 119 patients receiving OPAT treatment. Results showed no significant changes in weight or frailty index before and after treatment, and cognitive function remained stable in 85.6% of patients. This provides preliminary evidence for the application of OPAT in elderly patients and those with multiple comorbidities.

Literature Overview
This article, "Preserving Health Beyond Infection Control: Frailty, Weight, and Cognition in OPAT Patients," published in the journal Antibiotics, reviews and summarizes the impact of Outpatient Parenteral Antibiotic Therapy (OPAT) on health-related indicators such as frailty, weight, and cognitive function in patients. The study indicates that OPAT is not only effective in infection control but may also have potential benefits in maintaining overall patient health, especially among elderly patients or those with multiple comorbidities. A total of 119 patients were included, of which 56.3% were male, with a median age of 67 years. Common comorbidities included ischemic heart disease, diabetes, chronic lung disease, and solid tumors. Infection types were mainly urinary tract infections, osteomyelitis, and pneumonia, with multidrug-resistant organisms isolated in 66% of cases. Using the Rockwood Clinical Frailty Index and subjective cognitive assessments, this study analyzed patients' physical condition and cognitive changes before and after treatment, suggesting that OPAT did not cause significant decline in weight or frailty during the treatment period, and cognitive function remained stable in most patients.

Background Knowledge
Outpatient Parenteral Antibiotic Therapy (OPAT) has been well-established as a proven alternative to inpatient hospitalization for managing complex or deep-seated infections. Although numerous studies have assessed its efficacy, safety, and cost-effectiveness, there has been a lack of systematic evaluation of OPAT's impact on overall health indicators such as nutritional status, frailty, and cognitive function. Hospitalization is known to be associated with adverse health events like malnutrition, frailty, and delirium, especially in elderly patients or those with multiple comorbidities. Therefore, investigating whether OPAT can control infections while preserving physiological and cognitive function is important for optimizing treatment strategies and improving patient quality of life. This study retrospectively analyzed data from two tertiary hospitals to assess the impact of OPAT on frailty, weight, and cognition, providing a foundation for future prospective studies.

Research Methods and Experiments
This was a multicenter retrospective observational study that enrolled 139 patients who received OPAT treatment between April 2024 and July 2025. A total of 119 patients with complete data and follow-up were included in the final analysis. Baseline data collected included demographics, comorbidities, weight, the Rockwood Clinical Frailty Index (CFI), and infection-related variables. Weight, frailty index, and subjective cognitive status were assessed during follow-up. Primary endpoints included clinical outcomes (recovery, readmission, mortality), adverse events, and hospitalization days saved. Additionally, antibiotic administration strategies were recorded, including once-daily dosing and elastomeric pump continuous infusion, along with adverse reactions and catheter-related complications.

Key Conclusions and Perspectives

• Among the 119 OPAT patients, 82.5% recovered, 16% required readmission, and no deaths were reported.
• No significant weight changes were observed before and after treatment (median 73 vs. 73 kg, p = 0.43), indicating OPAT does not negatively impact nutritional status.
• The Rockwood CFI score also showed no significant change before and after treatment (median 2.5 vs. 2.4, p = 0.16), suggesting OPAT does not worsen frailty.
• In cognitive assessments, 85.6% of patients self-reported no change in cognitive function, 5.9% reported cognitive decline, and 8.5% reported improvement, indicating that OPAT does not cause cognitive deterioration in most patients.
• This study highlights that OPAT not only effectively controls infections but may also help maintain overall health status, avoiding hospitalization-associated functional decline.

Conclusion
This study is the first to systematically evaluate the impact of OPAT on health status beyond infection control, finding that weight and frailty indices remained stable during treatment, and cognitive function did not significantly decline in most patients. These results support the view that OPAT is not only clinically effective but may also help maintain overall health in elderly or multimorbid patients, avoiding hospitalization-associated functional decline. Future larger-scale prospective studies incorporating standardized geriatric assessments and cognitive evaluation tools are needed to further validate OPAT’s role in multidimensional health preservation. These findings provide new insights into optimizing antibiotic treatment strategies and improving patient quality of life, particularly in the management of multidrug-resistant infections.

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