Attention to age: similar dosing regimens lead to different vancomycin levels among older and younger patients

• Published in: Age and ageing 2020-01, Vol.49 (1), p.26-31
• Main Authors: Yahav, Dafna, Abbas, Maria, Nassar, Laila, Ghrayeb, Alia, Shepshelovich, Daniel, Kurnik, Daniel, Leibovici, Leonard, Paul, Mical
• Format: Article
• Language: English
• Subjects: Age differences; Antibiotics; Dosage; Drug resistance; Glomerular filtration rate; Infections; Methicillin; Minimum inhibitory concentration; Mortality; Mortality rates; MRSA; Older people; Prospective studies; Staphylococcus aureus; Staphylococcus infections; Toxicity; Vancomycin
• ISSN: 0002-0729; 1468-2834
• DOI: 10.1093/ageing/afz135

Abstract Background little is known on the clinical implications of vancomycin trough levels among older patients. Objective to evaluate the association between vancomycin levels and outcomes among older versus younger patients. Design retrospective study. Subjects patients aged 18–64 and ≥65 years treated with vancomycin for documented methicillin resistant Staphylococcus aureus (MRSA) infections. Methods we compared the effectiveness and toxicity of vancomycin according to trough levels in older versus younger patients. Subgroup analysis of patients with glomerular filtration rate (GFR) > 60 ml/min/1.73 m2 was performed. Results we included 181 patients aged ≥65 years and 104 younger patients. Mean age in the older group was 76.9 ± 8 years versus 50.9 ± 12.4 in the younger group. Vancomycin trough levels and 24-hours area under the curve to minimal inhibitory concentrations (AUC/MIC) were significantly higher in older patients who were also significantly more likely to achieve trough levels of ≥15 mg/l within 4 days, (98/181 (54.1%) vs. 38/104 (36.5%) in younger patients, P = 0.004). Results were similar among patients with GFR > 60. Thirty-day mortality was significantly higher in older (74/181, 40.9% vs. 13/104, 12.5%, respectively, P