In 2006, it was determined that admission heart rate (AHR) may be used to predict in-hospital mortality in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and respiratory failure (RF). This was revealed in a published study. BMC Respiratory Medicine.

Researchers found that AECOPD, classified as mild, moderate, and severe, is one of the most common causes of hospitalization, and patients with severe AECOPD often experience rapid deterioration and require hospitalization. I explained. They noted that patients who frequently experience AECOPD have a decreased quality of life and accelerated decline in lung function, and RF contributes most to the high mortality rate and poor prognosis of these patients.

Previous studies have linked AHR (defined by researchers as the first measurable heart rate measured during initial hospitalization) to increased short-term and long-term mortality in patients discharged after acute myocardial infarction. Ta. The researchers noted that previous studies have also found that COPD patients are at increased risk for cardiovascular disease, as they die more frequently from cardiovascular disease than from respiratory disease. As a result, researchers expressed the need to analyze the relationship between AHR and in-hospital mortality in AECOPD/RF patients.

Hospital bed | Image credit: catinsyrup – Stock.adobe.com

To investigate this relationship, researchers targeted patients aged 40 years and older diagnosed with AECOPD and RF at the First Affiliated Hospital of Jinzhou Medical University in China from January 2021 to March 2023. A single-center retrospective analysis was performed. The outcome measure was all-cause in-hospital mortality.

They enrolled all patients admitted with a primary diagnosis of AECOPD based on Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria and a confirmed RF diagnosis by arterial blood gas analysis. Conversely, researchers excluded people younger than 40 years of age, those for whom heart rate data were not available, those with a history of multiple hospitalizations, those with incomplete data, and those with an AHR less than 35 beats/min. did.

The researchers used patient demographics, vital signs, laboratory tests, outcomes, diagnosis and treatment information for their analysis. All patient demographic information and laboratory data were extracted from the hospital’s electronic medical system, and comorbidities were diagnosed based on patient medical history and medication use.

Initially, researchers identified 510 eligible patients, but only 397 were included in the analysis. Average (standard deviation) [SD]) The age of patients in the study cohort was 72.6 (9.5) years, and 49.4% of patients were female. Also, the medical history of the study population included type II RF (n = 266), cor pulmonale (n = 187), heart failure (n = 167), hypertension (n = 135), type I RF (n = 131), diabetes (n = 43). In addition, 261 patients used inhaled corticosteroids (ICS) and 199 used mechanical ventilation.

Overall, in-hospital mortality was 5%. The researchers explained that the non-hospital survival group was older and had a shorter hospital stay than the hospital survival group (P < .05). Regarding the mean (SD) AHR, the AHR of patients in the non-survival group (107.0) [21.8] heart rate/min) was higher than that of the survival group (96.2) [18.2] beats/min. P = .011).

Both multivariate logistic regression analysis and smooth curve fitting revealed a nonlinear association between AHR and in-hospital mortality in the study population, with 100 beats/min representing an inflection point. They found that each beat/min AHR increase above 100 beats/min had an odds ratio (OR) of 1.094 (95% CI, 1.01-1.186; P = .0281). In other words, an AHR greater than 100 beats/min was a potential predictor of mortality, and the researchers claimed that each 1 beat/min increase in AHR was associated with a 9.4% increase in mortality.

Conversely, for patients with AHR <100 beats/min, the effect size (OR) was 0.474 (95% CI, 0.016-13.683; P = .6635); there was no significant difference in survival among patients with AHR <100 beats/min.

The researchers acknowledged their study had limitations, one of which was that it was a single-center study with a small sample size. Therefore, the possibility of selection bias and the lack of a validation cohort must be considered. Additionally, we were unable to obtain all baseline characteristics of the patients, which may have resulted in biased results.

The researchers suggested designing future studies to address these limitations to validate and extend their findings. However, they expressed confidence in their findings despite their limitations.

“AHR was associated with increased all-cause in-hospital mortality in patients with AECOPD and RF,” the authors concluded. “Therefore, as a simple and easily accessible parameter, elevated AHR should serve as a risk signal to alert respiratory physicians for early intervention.”

reference

Zhou R, Pan D. Association between admission heart rate and in-hospital mortality in patients with acute exacerbation of chronic obstructive pulmonary disease and respiratory failure: a retrospective cohort study. BMC Palm Med. 2024;24(1):111. doi:10.1186/s12890-024-02934-w