Outcomes in high and low volume hospitals in patients with acute hematochezia in a cohort study

Ishii, Naoki; Nagata, Naoyoshi; Kobayashi, Katsumasa; Yamauchi, Atsushi; Yamada, Atsuo; Omori, Jun; Ikeya, Takashi; Aoyama, Taiki; Tominaga, Naoyuki; Sato, Yoshinori; Kishino, Takaaki; Sawada, Tsunaki; Murata, Masaki; Takao, Akinari; Mizukami, Kazuhiro; Kinjo, Ken; Fujimori, Shunji; Uotani, Takahiro; Fujita, Minoru; Sato, Hiroki; Suzuki, Sho; Narasaka, Toshiaki; Hayasaka, Junnosuke; Funabiki, Tomohiro; Kinjo, Yuzuru; Mizuki, Akira; Kiyotoki, Shu; Mikami, Tatsuya; Gushima, Ryosuke; Fujii, Hiroyuki; Fuyuno, Yuta; Gunji, Naohiko; Toya, Yosuke; Narimatsu, Kazuyuki; Manabe, Noriaki; Nagaike, Koji; Kinjo, Tetsu; Sumida, Yorinobu; Funakoshi, Sadahiro; Kawagishi, Kana; Matsuhashi, Tamotsu; Komaki, Yuga; Miki, Kuniko; Watanabe, Kazuhiro; Omata, Fumio; Shiratori, Yasutoshi; Imamura, Noriatsu; Yano, Takahiko; Kaise, Mitsuru

Outcomes of acute lower gastrointestinal bleeding have not been compared according to hospital capacity. We aimed to perform a propensity score-matched cohort study with path and mediation analyses for acute hematochezia patients. Hospitals were divided into high- versus low-volume hospitals for emergency medical services. Rebleeding and death within 30 days were compared. Computed tomography, early colonoscopy (colonoscopy performed within 24 h), and endoscopic therapies were included as mediators. A total of 2644 matched pairs were yielded. The rebleeding rate within 30 days was not significant between high- and low-volume hospitals (16% vs. 17%, P = 0.44). The mortality rate within 30 days was significantly higher in the high-volume cohort than in the low-volume cohort (1.7% vs. 0.8%, P = 0.003). Treatment at high-volume hospitals was not a significant factor for rebleeding (odds ratio [OR] = 0.91; 95% confidence interval [CI], 0.79–1.06; P = 0.23), but was significant for death within 30 days (OR = 2.03; 95% CI, 1.17–3.52; P = 0.012) on multivariate logistic regression after adjusting for patients’ characteristics. Mediation effects were not observed, except for rebleeding within 30 days in high-volume hospitals through early colonoscopy. However, the direct effect of high-volume hospitals on rebleeding was not significant. High-volume hospitals did not improve the outcomes of acute hematochezia patients.