TIME-VARYING EXUDATE SEVERITY AND DELAYED HEALING IN PRESSURE INJURIES: A REAL-WORLD COHORT ANALYSIS
Author(s)
Jan Kottner, PhD1, Grace Gahlon, PhD2, Vladica M. Velickovic, PhD, MD3, Yun Han, PhD2, Cornelia Santoso, PhD4, Anitha Pitchika, PhD4, Shelby Corman, MS, PharmD5, Peter Gloviczki, PhD, MD6, David G. Armstrong, PhD, MD7, Kenneth Rothman, PhD8.
1Charité-Universitätsmedizin, Berlin, Germany, 2Precision AQ, New York, NY, USA, 3Head of Evidence Generation, Hartmann group, Neu-Ulm, Germany, 4Hartmann group, Heidenheim, Germany, 5Precision AQ, Gladstone, NJ, USA, 6Hartmann group, Phoenix, AZ, USA, 7Keck School of Medicine of University of Southern California, Los Angeles, CA, USA, 8Boston University School of Public Health, Boston, MA, USA.
1Charité-Universitätsmedizin, Berlin, Germany, 2Precision AQ, New York, NY, USA, 3Head of Evidence Generation, Hartmann group, Neu-Ulm, Germany, 4Hartmann group, Heidenheim, Germany, 5Precision AQ, Gladstone, NJ, USA, 6Hartmann group, Phoenix, AZ, USA, 7Keck School of Medicine of University of Southern California, Los Angeles, CA, USA, 8Boston University School of Public Health, Boston, MA, USA.
OBJECTIVES: To quantify the relationship between evolving exudate severity and both wound closure and time spent unhealed in pressure injuries (PIs), with emphasis on evidence relevant to prognosis and resource planning.
METHODS: U.S. outpatient wound center records (2002-2020) were analyzed retrospectively. The analytic cohort comprised non-device-related stage 2 to 4 PIs, excluding deep-tissue PIs, with an initial surface area of 2.0-100.0 cm² and at least one subsequent visit. Clinicians graded exudate at each assessment as none, mild, moderate, or heavy, analyzed as a time-varying exposure. The endpoint was complete healing (i.e., documented healing, closure, resolution, or treatment completion). Stabilized inverse probability-of-treatment and censoring weights were incorporated into marginal structural models to mitigate time-dependent confounding and informative censoring. Weighted Royston-Parmar flexible parametric survival models generated hazard ratios (HRs), standardized 52-week healing probabilities, and restricted mean survival time (RMST) representing days unhealed.
RESULTS: The analysis included 11,737 PIs among 6,965 patients (mean age, 67.0 years; 50.8% male). Compared with no exudate, the hazard of healing was reduced for mild (HR, 0.12; 95% CI, 0.08-0.17), moderate (HR, 0.07; 0.04-0.11), and heavy exudate (HR, 0.002; 0.001-0.005). RMST estimates were 42, 269, 306, and 356 unhealed days, corresponding to 226, 264, and 313 additional days for mild, moderate, and heavy exudate. Standardized 52-week healing estimates were 99.9% (no exudate), 41.1% (mild), 25.6% (moderate), and 4.5% (heavy). Because median follow-up was 56 days, later estimates relied on model extrapolation. The outcome definition included treatment completion, which may not reflect closure.
CONCLUSIONS: Increasing exudate severity was associated with progressively slower PI healing and more time spent unhealed. These findings should be interpreted as prognostic associations across the exudate gradient. Persistent exudate may reflect underlying wound chronicity, while potentially contribute to, a biologically active wound environment that promotes chronicity, reinforcing the clinical importance of exudate assessment and management.
METHODS: U.S. outpatient wound center records (2002-2020) were analyzed retrospectively. The analytic cohort comprised non-device-related stage 2 to 4 PIs, excluding deep-tissue PIs, with an initial surface area of 2.0-100.0 cm² and at least one subsequent visit. Clinicians graded exudate at each assessment as none, mild, moderate, or heavy, analyzed as a time-varying exposure. The endpoint was complete healing (i.e., documented healing, closure, resolution, or treatment completion). Stabilized inverse probability-of-treatment and censoring weights were incorporated into marginal structural models to mitigate time-dependent confounding and informative censoring. Weighted Royston-Parmar flexible parametric survival models generated hazard ratios (HRs), standardized 52-week healing probabilities, and restricted mean survival time (RMST) representing days unhealed.
RESULTS: The analysis included 11,737 PIs among 6,965 patients (mean age, 67.0 years; 50.8% male). Compared with no exudate, the hazard of healing was reduced for mild (HR, 0.12; 95% CI, 0.08-0.17), moderate (HR, 0.07; 0.04-0.11), and heavy exudate (HR, 0.002; 0.001-0.005). RMST estimates were 42, 269, 306, and 356 unhealed days, corresponding to 226, 264, and 313 additional days for mild, moderate, and heavy exudate. Standardized 52-week healing estimates were 99.9% (no exudate), 41.1% (mild), 25.6% (moderate), and 4.5% (heavy). Because median follow-up was 56 days, later estimates relied on model extrapolation. The outcome definition included treatment completion, which may not reflect closure.
CONCLUSIONS: Increasing exudate severity was associated with progressively slower PI healing and more time spent unhealed. These findings should be interpreted as prognostic associations across the exudate gradient. Persistent exudate may reflect underlying wound chronicity, while potentially contribute to, a biologically active wound environment that promotes chronicity, reinforcing the clinical importance of exudate assessment and management.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
RWD163
Topic
Clinical Outcomes, Medical Technologies, Real World Data & Information Systems
Topic Subcategory
Health & Insurance Records Systems
Disease
Injury & Trauma, Sensory System Disorders (Ear, Eye, Dental, Skin)