Analysis of in-hospital deaths in patients with critical limb ischemia necessitating invasive treatments: based on a Japanese nationwide database

Kiwamu Iwata; Manabu Nitta; Makoto Kaneko; Kiyohide Fushimi; Shinichiro Ueda; Sayuri Shimizu

doi:10.1007/s12928-024-01003-7

Analysis of in-hospital deaths in patients with critical limb ischemia necessitating invasive treatments: based on a Japanese nationwide database

Cardiovasc Interv Ther. 2024 Apr 30. doi: 10.1007/s12928-024-01003-7. Online ahead of print.

Authors

Kiwamu Iwata^#^{1

2}, Manabu Nitta^#^{3

4

5}, Makoto Kaneko⁶, Kiyohide Fushimi⁷, Shinichiro Ueda^{6

8}, Sayuri Shimizu⁶

Affiliations

¹ Department of Cardiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-0004, Japan.
² Wellbe Heart Clinic Konandai, 3-19-1-1F, Konandai, Konan, Yokohama, Kanagawa, 234-0054, Japan.
³ Department of Cardiology, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-0004, Japan. mnitta@yokohama-cu.ac.jp.
⁴ Center for Novel and Exploratory Clinical Trials (Y-NEXT), Yokohama City University Hospital, 1-1-1-5F Fukuura, Kanazawa, Yokohama, Kanagawa, 236-0004, Japan. mnitta@yokohama-cu.ac.jp.
⁵ Department of Health Data Science, Graduate School of Data Science, Yokohama City University, 22-2 Seto, Kanazawa, Yokohama, Kanagawa, Japan. mnitta@yokohama-cu.ac.jp.
⁶ Department of Health Data Science, Graduate School of Data Science, Yokohama City University, 22-2 Seto, Kanazawa, Yokohama, Kanagawa, Japan.
⁷ Department of Health Policy and Informatics, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
⁸ Department of Clinical Pharmacology and Therapeutics, University of the Ryukyus Graduate School of Medicine, 207 Uehara, Nishihara-cho, Okinawa, 903-0215, Japan.

^# Contributed equally.

PMID: 38689203
DOI: 10.1007/s12928-024-01003-7

Abstract

Critical limb ischemia (CLI) is associated with systemic cardiovascular and non-cardiovascular diseases. Treatments primarily targeting limb-related outcomes may not improve overall life prognosis. We aimed to describe in-hospital mortality and the underlying etiologies in Japanese patients with CLI. We analyzed the Diagnosis Procedure Combination (DPC) database from approximately 1200 Japanese acute-care hospitals between April 2018 and March 2020. The definition of patients with CLI was based on the diagnostic codes listed as the most resource-intensive diagnosis and information regarding invasive procedures (endovascular treatment, bypass, or amputation). The DPC database provides information on whether in-hospital death was caused by the most resource-intensive diagnosis. Among 15,228 distinct patients with CLI, we identified 18,970 records, including 5,378 amputations. In-hospital death occurred in 1238 (6.5%) patients. Among them, 811 (65.5%) were due to causes unrelated to CLI. In patients who underwent amputation (n = 5378), causes unrelated to CLI accounted for 70.0% of in-hospital deaths, whereas among patients who did not undergo amputation (n = 13,592), this proportion was 60.1%. When compared to patients who died due to causes related to CLI, the prevalence of male patients was higher (62.6% vs 52.7%, p = 0.001), and amputation was more frequently performed (58.0% vs 47.1%, p < 0.001) in those who died due to causes unrelated to CLI. The majority of in-hospital deaths among patients with CLI necessitating endovascular treatment, bypass, or amputation were attributable to factors unrelated to the primary condition of CLI. Managing systemic cardiovascular and non-cardiovascular diseases beyond the affected limb is crucial to improve the prognosis of these patients.

Keywords: Amputation; Cause of death; Critical limb ischemia; Diagnosis Procedure Combination (DPC); In-hospital mortality.