Vertebral fractures and mortality risk in hospitalised patients during the COVID-19 pandemic emergency

Background and objective Bone fragility has been linked to COVID-19 severity. The objective of this study was to evaluate whether a diagnosis of vertebral fracture (VF) increased mortality risk in COVID-19 patients and whether this effect was greater than in those without COVID-19. Methods We assessed VFs by computed tomography (CT) in a cohort of 501 patients consecutively admitted to the emergency department (ED) for clinical suspicion of SARS-CoV-2 infection during the first wave of pandemic emergency. Of those, 239 had a confirmed diagnosis of COVID-19. Results VF prevalence was similar between COVID-19 and non-COVID-19 groups (22.2 vs. 19%; p = 0.458). Death rates were similar between COVID-19 and non-COVID-19 groups at both 30 (15.8 vs. 12.2%; p = 0.234) and 120 days (21.8 vs. 17.6%; p = 0.236). The mortality risk was higher in COVID-19 patients either with one or multiple fractures compared to those without VFs, at 30 and 120 days, but statistical significance was reached only in those with multiple VFs (30-day HR 3.03, 95% CI 1.36-6.75; 120-day HR 2.91, 95% CI 1.43-5.91). In the non-COVID-19 group, the 30-day mortality risk was significantly higher in patients either with one (HR 7.46, 95% CI 3.12-17.8) or multiple fractures (HR 6.2, 95% CI 2.75-13.98) compared to those without VFs. A similar effect was observed at 120 days. After adjustment for age, sex and bone density, mortality risk remained associated with VFs in the non-COVID-19 group only. Conclusions VFs were not independently associated with short-term mortality in patients with COVID-19, but they strongly increased mortality risk in those without COVID-19.