Xu Yilin, Fang Jianhua, Kang Xiuhua, Xiang Tianxin
Infection Control and Prevention Department, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, China.
Jiangxi Provincial Key Laboratory of Prevention and Treatment of Infectious Diseases, First Affiliated Hospital of Nanchang University, Nanchang, China.
Lab Med. 2025 Mar 10;56(2):178-186. doi: 10.1093/labmed/lmae079.
The prevalence of anemia in patients with community-acquired pneumonia (CAP) has been well described. However, few studies have explored its association with short-term and long-term mortality risk in CAP patients.
We aimed to investigate the associations between hemoglobin concentrations at baseline and 14-day and 1-year mortality risk in a CAP population with a large sample size. Our data originated from the Dryad database, including a dataset from the study "Incidence rate of community-acquired pneumonia in adults: a population-based prospective active surveillance study in 3 cities in South America." A total of 1463 study samples with follow-up data from the dataset were enrolled for our analysis.
During the follow-up period of 3 years, the 14-day risk and 1-year mortality risk were 206 (14.08%) and 401 (27.41%), respectively, among these CAP patients. Curve analysis indicated a strong U-shaped relationship between blood hemoglobin concentrations and 14-day mortality (r = -0.191, P < .001) and 1-year mortality (r = -0.220, P < .001). The blood hemoglobin level with the lowest point of mortality risk was 14.5 g/dL, suggesting that an increased hemoglobin concentration contributed to reduced 14-day and 1-year mortality risk in CAP patients when hemoglobin does not exceed 14.5 g/dL even if it is within the normal clinical range. In addition, we also observed significant associations of hemoglobin with 14-day mortality risk (odds ratio [OR] = 0.817; 95% CI, 0.742-0.899 P < .001) and 1-year mortality risk (OR = 0.834; 95% CI, 0.773-0.900; P < .001), but only in participants without risk factors for health care-associated pneumonia (HCAP) rather than in participants with risk factors for HCAP.
The greatest discovery is that our findings indicated a significant U-shaped relationship between hemoglobin levels and 14-day and 1-year mortality risk in CAP patients. However, a significant relationship was only discovered in subjects without risk factors for HCAP. More evidence is needed to support this finding.
社区获得性肺炎（CAP）患者贫血的患病率已有详尽描述。然而，很少有研究探讨其与CAP患者短期和长期死亡风险的关联。
我们旨在调查在一个大样本量的CAP人群中，基线血红蛋白浓度与14天和1年死亡风险之间的关联。我们的数据源自Dryad数据库，包括来自“成人社区获得性肺炎发病率：南美洲3个城市基于人群的前瞻性主动监测研究”的数据集。总共纳入了该数据集中有随访数据的1463个研究样本进行分析。
在3年的随访期内，这些CAP患者中14天风险和1年死亡风险分别为206例（14.08%）和401例（27.41%）。曲线分析表明，血红蛋白浓度与14天死亡率（r = -0.191，P <.001）和1年死亡率（r = -0.220，P <.001）之间存在强烈的U型关系。死亡风险最低点的血红蛋白水平为14.5 g/dL，这表明当血红蛋白浓度不超过14.5 g/dL时，即使在正常临床范围内，其升高也有助于降低CAP患者的14天和1年死亡风险。此外，我们还观察到血红蛋白与14天死亡风险（优势比[OR] = 0.817；95%置信区间，0.742 - 0.899；P <.001）和1年死亡风险（OR = 0.834；95%置信区间，0.773 - 0.900；P <.001）之间存在显著关联，但仅在无医疗保健相关肺炎（HCAP）危险因素的参与者中存在，而在有HCAP危险因素的参与者中未发现。
最大的发现是我们的研究结果表明CAP患者的血红蛋白水平与14天和1年死亡风险之间存在显著的U型关系。然而，仅在无HCAP危险因素的受试者中发现了显著关系。需要更多证据来支持这一发现。
