Retrospective Study of Factors Affecting the Accuracy of Predicting Vancomycin Concentrations in Patients Aged 75 Years and Above

• Published in: Medicina (Kaunas, Lithuania) Vol. 60; no. 8; p. 1273
• Main Authors: Takigawa, Masaki, Tanaka, Hiroyuki, Kinoshita, Masako, Ishii, Toshihiro, Masuda, Masayuki
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 07.08.2024; MDPI
• Subjects: Accuracy; Aged; Aged, 80 and over; Anti-Bacterial Agents - blood; Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - therapeutic use; Bland–Altman plot; Creatinine; Creatinine - blood; creatinine clearance; Female; Geriatrics; Gerontology; Humans; Japan; Male; Medical research; Medicine, Experimental; Methicillin; older people; Patients; predictive performance; Retrospective Studies; Software; Staphylococcus aureus; Staphylococcus aureus infections; Staphylococcus infections; therapeutic drug monitoring; Vancomycin; Vancomycin - blood; Vancomycin - pharmacokinetics; Vancomycin - therapeutic use; Japan; vancomycin; older people; creatinine clearance; Bland–Altman plot; therapeutic drug monitoring; predictive performance
• ISSN: 1648-9144; 1010-660X; 1648-9144
• DOI: 10.3390/medicina60081273

: The predicted serum concentrations of vancomycin are determined using population pharmacokinetic parameters. However, the accuracy of predicting vancomycin serum concentrations in the older population remains unclear. Therefore, this study aimed to investigate the accuracy of predicting vancomycin serum concentrations and identifying elements that diminish the prediction accuracy in older people. : A total of 144 patients aged 75 years or older were included. The serum vancomycin concentrations in the patients were predicted based on population pharmacokinetic parameters common in Japan. We examined the accuracy of serum vancomycin concentration prediction in elderly individuals by comparing the predicted and measured serum vancomycin concentrations in each patient. The prediction accuracy was evaluated using the mean prediction error (ME) and mean absolute error of prediction (MAE) calculated from the measured and predicted serum vancomycin concentrations in each patient. : The ME for all patients was 0.27, and the 95% CI included 0, indicating that the predicted values were not significantly biased compared to the measured values. However, the predicted serum concentrations in the <50 kg body weight and serum creatinine (Scr) < 0.6 mg/dL groups were significantly biased compared to the measured values. The group with a history of intensive care unit (ICU) admission showed the largest values for the ME and MAE. : Our prediction accuracy was satisfactory but tended to be lower in underweight patients, those with low creatinine levels, and patients admitted to the ICU. Patients with multiple of these factors may experience a greater degree of decreased predictive accuracy.