Anaemia in the first week may be associated with long-term mortality among critically ill patients: propensity score-based analyses

I-Hung Lin; Pei-Ya Liao; Li-Ting Wong; Ming-Cheng Chan; Chieh-Liang Wu; Wen-Cheng Chao

doi:10.1186/s12873-023-00806-w

Anaemia in the first week may be associated with long-term mortality among critically ill patients: propensity score-based analyses

BMC Emerg Med. 2023 Mar 22;23(1):32. doi: 10.1186/s12873-023-00806-w.

Authors

I-Hung Lin¹, Pei-Ya Liao¹, Li-Ting Wong², Ming-Cheng Chan^{3

4}, Chieh-Liang Wu^{5

6

7

8}, Wen-Cheng Chao^{9

10

11

12

13}

Affiliations

¹ Division of Chest Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
² Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan.
³ Division of Critical Care and Respiratory Therapy, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
⁴ College of Science, Tunghai University, Taichung, Taiwan.
⁵ Department of Critical Care Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
⁶ Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan.
⁷ Department of Industrial Engineering and Enterprise Information, Tunghai University, Taichung, Taiwan.
⁸ Artificial Intelligence Studio, Taichung Veterans General Hospital, Taichung, Taiwan.
⁹ Department of Critical Care Medicine, Taichung Veterans General Hospital, Taichung, Taiwan. cwc081@hotmail.com.
¹⁰ Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan. cwc081@hotmail.com.
¹¹ Department of Automatic Control Engineering, Feng Chia University, Taichung, Taiwan. cwc081@hotmail.com.
¹² Big Data Center, Chung Hsing University, Taichung, Taiwan. cwc081@hotmail.com.
¹³ Taichung Veterans General Hospital, No, 1650, Section 4, Taiwan Boulevard, Xitun District, Taichung City, 40705, Taiwan. cwc081@hotmail.com.

Abstract

Background: Anaemia is highly prevalent in critically ill patients; however, the long-term effect on mortality remains unclear.

Methods: We retrospectively included patients admitted to the medical intensive care units (ICUs) during 2015-2020 at the Taichung Veterans General Hospital. The primary outcome of interest was one-year mortality, and hazard ratios (HRs) with 95% confidence intervals (CIs) were determined to assess the association. We used propensity score matching (PSM) and propensity score matching methods, including inverse probability of treatment weighting (IPTW) as well as covariate balancing propensity score (CBPS), in the present study.

Results: A total of 7,089 patients were eligible for analyses, and 45.0% (3,189/7,089) of them had anaemia, defined by mean levels of haemoglobin being less than 10 g/dL. The standardised difference of covariates in this study were lower than 0.20 after matching and weighting. The application of CBPS further reduced the imbalance among covariates. We demonstrated a similar association, and adjusted HRs in original, PSM, IPTW and CBPS populations were 1.345 (95% CI 1.227-1.474), 1.265 (95% CI 1.145-1.397), 1.276 (95% CI 1.142-1.427) and 1.260 (95% CI 1.125-1.411), respectively.

Conclusions: We used propensity score-based analyses to identify that anaemia within the first week was associated with increased one-year mortality in critically ill patients.

Keywords: Anaemia; Critical illness; Long-term outcome; Propensity score.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anemia*
Critical Illness*
Hemoglobins
Humans
Propensity Score
Retrospective Studies

Substances

Hemoglobins