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Timing of colonoscopy in acute lower GI bleeding: a multicenter retrospective cohort study
Yasutoshi Shiratori1, Naoki Ishii2, Tomonori Aoki3
1Department of Gastroenterology, St Luke's International University, Tokyo, Japan.
Insights
Early colonoscopy for acute lower GI bleeding improves identification of hemorrhage but increases rebleeding risk. It benefits patients with shock index ≥1 or poor performance status, without improving mortality.
Area of Science:
- Gastroenterology
- Endoscopy
- Clinical Research
Background:
- Acute lower gastrointestinal bleeding (LGIB) is a common medical emergency.
- Determining the optimal timing for colonoscopy in LGIB is crucial for patient outcomes.
- Early colonoscopy may improve diagnostic yield but could increase risks.
Purpose of the Study:
- To evaluate the optimal timing of colonoscopy for patients with acute lower GI bleeding.
- To identify patient factors that benefit from early colonoscopy.
- To assess the impact of colonoscopy timing on rebleeding rates, interventions, and mortality.
Main Methods:
- A retrospective analysis of 6270 patients with acute hematochezia from the CODE BLUE-J study.
- Patients were categorized into early (≤24 hours), elective (24-48 hours), and late (48-120 hours) colonoscopy groups.
- Inverse probability of treatment weighting was used to adjust for baseline characteristics; 30-day rebleeding rate was the primary outcome.
Main Results:
- Early colonoscopy (≤24 hours) significantly increased stigmata of recent hemorrhage (SRH) identification and shortened hospital stays.
- However, the 30-day rebleeding rate was significantly higher in the early colonoscopy group.
- Early colonoscopy showed a significant benefit in reducing the need for interventional radiology or surgery in patients with a shock index ≥1.
Conclusions:
- While early colonoscopy enhances SRH identification and reduces hospital stay, it increases rebleeding risk without improving mortality or intervention rates.
- Patients presenting with a shock index ≥1 or performance status ≥3 particularly benefit from early colonoscopy.
- The optimal timing of colonoscopy in acute LGIB should consider individual patient factors and risk-benefit profiles.
Background And Aims:
We aimed to determine the optimal timing of colonoscopy and factors that benefit patients who undergo early colonoscopy for acute lower GI bleeding.
Methods:
We identified 10,342 patients with acute hematochezia (CODE BLUE-J study) admitted to 49 hospitals in Japan. Of these, 6270 patients who underwent a colonoscopy within 120 hours were included in this study. The inverse probability of treatment weighting method was used to adjust for baseline characteristics among early (≤24 hours, n = 4133), elective (24-48 hours, n = 1137), and late (48-120 hours, n = 1000) colonoscopy. The average treatment effect was evaluated for outcomes. The primary outcome was 30-day rebleeding rate.
Results:
The early group had a significantly higher rate of stigmata of recent hemorrhage (SRH) identification and a shorter length of stay than the elective and late groups. However, the 30-day rebleeding rate was significantly higher in the early group than in the elective and late groups. Interventional radiology (IVR) or surgery requirement and 30-day mortality did not significantly differ among groups. The interaction with heterogeneity of effects was observed between early and late colonoscopy and shock index (shock index <1, odds ratio [OR], 2.097; shock index ≥1, OR, 1.095; P for interaction = .038) and performance status (0-2, OR, 2.481; ≥3, OR, .458; P for interaction = .022) for 30-day rebleeding. Early colonoscopy had a significantly lower IVR or surgery requirement in the shock index ≥1 cohort (OR, .267; 95% confidence interval, .099-.721) compared with late colonoscopy.
Conclusions:
Early colonoscopy increased the rate of SRH identification and shortened the length of stay but involved an increased risk of rebleeding and did not improve mortality and IVR or surgery requirement. Early colonoscopy particularly benefited patients with a shock index ≥1 or performance status ≥3 at presentation.
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