Hip fracture mortality in patients co-infected with coronavirus disease 2019: a comparison of the first two waves of the United Kingdom pandemic during the pre-vaccine era

AIMS: In the UK, deaths associated with COVID-19 have occurred in two waves. Evidence has shown an increase in 30-day mortality for hip fracture patients co-infected with COVID-19. However, there are no studies analysing mortality trends between the first two waves of the UK pandemic. Additionally, hospital versus community acquired COVID-19 infection between the two waves has not been analysed. Furthermore, predictive factors of 30-day mortality have not been fully evaluated. METHODS: Data from two audits conducted by the CHIP collaborative group were used: a published regional audit in England of nine hospitals providing the COVID-19 negative cases and an unpublished UK national audit of 43 hospitals, which provided the COVID-19 positive cases. Data collection for the COVID-19 positive cases was from 23 March to 31 December 2020. September 1, 2020 was used to define the transition between the two waves. RESULTS: There were 517 COVID-19 positive hip fracture patients and 1445 COVID-19 negative hip fracture patients. Overall, 30-day mortality rates were 5.7% in the COVID-19 negative group and 22.4% in the COVID-19 positive patients (p < 0.001). A difference in survival function between the first and second waves was found (p = 0.038). To allow for significant demographic differences, a matched analysis of 185 patients found a 26.5% 30-day mortality in the first wave compared to 21.1% in the second wave (p = 0.222). Within the COVID-19 positive groups, the virus was hospital acquired in 66.7% of cases in the first wave and 72.8% of cases in the second wave (p = 0.130). Independent predictors of mortality were found to include COVID-19 positive status, AMTS ≤ 6, male gender and age. CONCLUSION: There was a reduction in 30-day mortality for hip fracture patients co-infected with COVID-19 between the two UK pandemic waves but this was not statistically significant. There was no reduction in hospital acquired COVID-19 infection between the two waves.