P190 The impact of drug therapies on COVID-19 mortality in a UK tertiary centre

Introduction and ObjectivesThe availability of treatment options for Covid-19 is rapidly expanding. Whilst the efficacy data is well-established from clinical trials, real-life efficacy of drug therapies remains lacking. We aimed to compare clinical outcomes between first and second wave of Covid-19 and determine real-world effectiveness of dexamethasone on 30-day mortality.MethodsThis is a retrospective observational study. Clinical data and information regarding 30-day mortality, length of stay (LOS) and Intensive Care Unit (ICU) admission of hospitalised Covid-19 patients during early first wave (10.03.2020 to 13.04.2020) and second wave (01.12.2020 to 09.02.2021) were collected. Treatment was limited to second wave and included either dexamethasone only or both remdesivir and dexamethasone. The effectiveness of dexamethasone only on 30-day mortality was measured.ResultsOf 373 patients (64.3% male) during the first wave, 24.9% died within 30 days. The 30-day mortality rate was lower during the second wave (61/324, 18.8%, p-value= 0.064). Patients were younger (mean [SD], 60.0 [16.5] years) and had higher body mass index (mean [SD], 30.3 [11.0] kg/m2) during the second wave than the first wave (68.7 [14.8] years and 28.2 [7.70] kg/m2). In the first wave, no patients received specific drug therapy for Covid-19. However, 86.5% of patients received dexamethasone only during the second wave. The LOS for the first wave was longer (median (IQR): 5 (2–11) days) compared to the second wave (4 (2–9) days, p=0.013). ICU admission during the second wave (11.2%) was also lower than the first wave (23.4%, p<0.001). In second wave, 14.3% of patients who were given dexamethasone died within 30 days compared to 25% who had no treatment (p-value=0.088).ConclusionsIn the real-world setting, there was an improvement in mortality, shortened hospital LOS and lower ICU admission rate between early first and second waves of the pandemic. The major difference in treatment strategy between the two waves was the approval of drug therapies in hospitalised patients. Dexamethasone reduced the 30-day mortality, although it did not reach statistical significance, likely due to the retrospective nature and small sample size of this study. Our findings corroborate clinical trial data on the benefit of dexamethasone therapy.