Treatment Duration and Associated Outcomes for Skin and Soft Tissue Infections in Patients with Obesity or Heart Failure

BACKGROUND:Although existing literature supports durations of 5-7 days for skin and soft tissue infections (SSTIs), longer durations are commonly used. Obesity and heart failure (HF) have been associated with increased risk for treatment failure of SSTIs; however, whether prolonged antibiotic durations reduce the risk of treatment failure is unknown. We evaluated practice patterns for SSTIs in patients with obesity and/or HF and whether short antibiotic durations (≤8 days) were associated with treatment failure.METHODS:We performed a single-center, retrospective cohort study of inpatients between January 1, 2006, and December 30, 2016, with SSTIs based on International Classification of Diseases (ICD) coding, and obesity and/or HF. Charts were manually reviewed to collect demographic, clinical, treatment, and outcome data. Propensity score matching was used to estimate the risk of treatment failure between the 2 groups. Secondary outcomes included length of stay, 30-day readmission, and Clostridium difficile infection rates.RESULTS:A total of 207 patients were included. Forty-nine (23.7%) received a short antibiotic duration and 158 (76.3%) a long duration. The median duration of therapy (interquartile range [IQR]) was 7 (7-8) days in the short group and 14 (10-15) days in the long group. In the propensity score-matched cohort, 28 (28.6%) treatment failures occurred in the long group, as compared with 5 (10.2%) in the short group (P = .02), as well as a shorter length of stay (IQR) in the short- vs long-duration group (2 [2-3] vs 3 [2-5] days, respectively; P = .002). There was no difference in other secondary outcomes.CONCLUSIONS:The majority of patients with obesity or HF received a longer antibiotic course for SSTIs; however, a longer antibiotic course was not associated with lower treatment failure rates. Higher failure rates in the long-duration group may be reflective of clinical decisions made in the face of diagnostic uncertainty and warrant further evaluation.