External validation of the IMPROVE Bleeding Risk Assessment Model in medical patients

Abstract

The IMPROVE Bleed Risk Assessment Model (RAM) remains the only bleed RAM in hospitalised medical patients using 11 clinical and laboratory factors. The aim of our study was to externally validate the IMPROVE Bleed RAM. A retrospective chart review was conducted between October 1, 2012 and July 31, 2014. We applied the point scoring system to compute risk scores for each patient in the validation sample. We then dichotomised the patients into those with a score <7 (low risk) vs ≥ 7 (high risk), as outlined in the original study, and compared the rates of any bleed, non-major bleed, and major bleed. Among the 12,082 subjects, there was an overall 2.6 % rate of any bleed within 14 days of admission. There was a 2.12 % rate of any bleed in those patients with a score of < 7 and a 4.68 % rate in those with a score ≥ 7 [Odds Ratio (OR) 2.3 (95 % CI=1.8-2.9), p<0.0001]. MB rates were 1.5 % in the patients with a score of < 7 and 3.2 % in the patients with a score of ≥ 7, [OR 2.2 (95 % CI=1.6-2.9), p<0.0001]. The ROC curve was 0.63 for the validation sample. This study represents the largest externally validated Bleed RAM in a hospitalised medically ill patient population. A cut-off point score of 7 or above was able to identify a high-risk patient group for MB and any bleed. The IMPROVE Bleed RAM has the potential to allow for more tailored approaches to thromboprophylaxis in medically ill hospitalised patients.

<p>Platelet Count and Bleeding in Patients Receiving Anticoagulant Therapy for Venous Thromboembolism: Lesson from the RIETE Registry</p>

“…A number of prognostic scores have been developed with variable grades of complexity and reproducibility. [7][8][9][10] Unfortunately however, none of the evaluated bleeding scores has an adequate accuracy and power to accurately identify VTE patients at increased risk of major bleeding.…”

Reassessment of venous thromboembolism and bleeding risk in medical patients receiving VTE prophylaxis

“…This is in keeping with the original IMPROVE Bleed RAM derivation cohort, which stratified 9.7% patients as high bleed risk, and with a similar analysis of adult medical patients that used the same RAM . Other external validation studies of the Bleed RAM demonstrated a higher percentage of patients at high bleed risk (19%‐20.7%) …”

“…For the assessment of bleed risk, the IMPROVE Bleed RAM remains the only evidence‐derived RAM known to the authors. This tool was derived from the same population as its VTE counterpart, consists of 13 weighted risk factors, and has been validated in two external populations …”

Guidelines' risk assessment recommendations for venous thromboembolism prophylaxis: A comparison and implementability appraisal

“…This difference might be explained by the limited availability of evidence for bleeding risk assessment, resulting in different approaches within each guideline development group. Only recently the IMPROVE bleeding RAM was externally validated [33]. Approximately 20% of the patients were classified with high bleeding risk.…”