Prognostic Value of Vertebral Bone Density in the CT Scans of Sepsis Patients Admitted to the Intensive Care Unit

Abstract

Aim: To evaluate the prognostic value of vertebral bone mineral density (BMD) and its relationship with mortality using the computed tomography (CT) scans of sepsis patients admitted to the intensive care unit. Methods: In this retrospective study, patients diagnosed with sepsis at the intensive care unit between January and December 2022 were evaluated. Bone density was manually measured from the vertebral body using axial CT images. The relationship of clinical variables and patient outcomes with vertebral BMD, mortality, and mechanical ventilation was investigated. A lower BMD (osteoporosis) was defined as ≤100 HU. Results: The study included 213 patients (95 females, 44.6%). The mean age of all patients was 60.1±18.7 years. At least one comorbidity was present in 64.7% (n=138) of the patients, and the most common comorbidity was hypertension (n=73, 34.2%). The mortality rate was 21.1% (n=45), and the mechanical ventilation rate was 17.4% (n=37), both being statistically significantly higher among the patients with a lower BMD (36.4 vs. 12.9%; p<0.001 and 29.7 vs. 10.8%; p=0.001, respectively). The rate of a lower BMD was significantly higher in the mortality group (59.5 vs. 29.5%; p=0.001). In the regression analysis, a lower BMD [odds ratio (OR), 2.785; 95% confidence interval (CI): 1.231–6.346, p=0.014] was a significant independent predictor of mortality. Interobserver agreement for BMD measurement was excellent, with an intraclass correlation coefficient of 0.919 (95% CI: 0.904−0.951). Conclusion: Vertebral BMD is a strong independent predictor of mortality and can be easily and reproducible evaluated on the thoracoabdominal CT images of patients admitted to the intensive care unit with a diagnosis of sepsis.