The aim was to determine the influence of COVID-19 on 30-day mortality in hip fracture. Secondary aims were to examine: (1) predictors of COVID-19 on presentation and later in the admission; (2) rate of hospital-acquired COVID-19; (3) predictive value of negative swabs on admission.

A nationwide multicentre retrospective cohort study of all patients with hip fracture in all 17 Scottish hospitals in March-April. Demographics, blood results, COVID-19 status, Nottingham Hip Fracture Score (NHFS), management, length of stay (LOS), and 30-day mortality were recorded.

78/833 (9.4%) patients had COVID-19 (65 swab-proven). 30-day survival with COVID-19 was lower than without (65.4% vs 91%; p<0.001). COVID-19 within 7 days of admission (likely community-acquired) was independently associated with male sex (OR 2.34, p=0.040, CI 1.04–5.25) and COVID-19 symptoms (OR 15.56, CI 6.61–36.60, p<0.001). COVID-19 within 7–30 days (probable hospital-acquired) was independently associated with male sex (OR 1.73, CI 1.05–2.87, p=0.032), NHFS □7 (OR 1.91, CI 1.09–3.34, p=0.024), pulmonary disease (OR 1.68, CI 1.00–2.81, p=0.049), ASA □3 (OR 2.37, CI 1.13–4.97, p=0.022) and LOS □9 days (OR 1.98, CI 1.18–3.31, p=0.009). 38/65 (58.5%) of COVID-19 cases were probably hospital-acquired. The false negative rate of swabs on admission was 0% in asymptomatic and 2.9% in symptomatic patients.

COVID-19 was associated with a threefold-increased 30-day mortality. Nosocomial transmission may have accounted for half of all cases. Identification of risk factors for having COVID-19 on admission, or acquiring COVID-19 later, may guide patient pathways. LOS was the only modifiable risk factor, emphasising the importance of high-quality, timely care.