ABSTRACT
Purpose: To better know the impact and characteristics of Covid-19 in renal patients, the Spanish Society of Nephrology set up a voluntary registry in March, 2020 Methods: Retrospective observational study of KT recipients included in the Spanish Covid-19 Registry (1st March to 14th November, 2020). We applied Cox multivariate analysis to identify risk factors for mortality and Kaplan-Meier and log rank survival analysis. Results: 1080 KT with Covid-19 were registered, having 937 (86.1%) their outcome reported (cure or death). Most were men (63.2%), mean age 60 years infected a median of 72 months postransplantation. Death occurred in 204 patients. Multivariate analysis found age, neumonia and KT within the last 6 months before Covid-19 were risk factors for mortality and gastrointestinal symptoms were protective. Survival analysis showed significant increasing mortality risk in four subgroups: age<65 years&postransplant time> 6mo (n=526), age<65×<6mo (n=49), age>65× >6mo (n=325) and age>65×<6mo (n=31)($$graphic). Of 1080 cases, 605 correspond to the first wave (1stW until June2020) and 475 to the second wave (2ndW). In the 2ndW, KT were younger (56.4 vs 61.1yr;p=.000), 15.8% were asymptomatic (p=.000) and presented less pneumonia (50.3% vs. 78%;p=.000). Fever, lymphopenia and respiratory symptoms were less frequent but gastrointestinal symptoms similar (30.9% vs. 34.2%;p=.256). Treatment has changed, with more use of remdesivir (p=.000) and steroids (p=.018), no use of ritonavir/lopinavir, hidroxycloroquine andazitromycin (p=.000), and no treatment in (37.1% vs 6.3% in 1stW, p=.000). Hospitalization decreased (89.2% vs. 63.2%;p=.000) but more KT were admitted to critical care units (14.5% vs 20%;p=.058). We found lower mortality (overall 26.4% vs 14.8%;p=.000, hospitalized 29% vs 23%;p=.088). Multivariate analysis of the 2ndW shows again that age, pneumonia and recent transplant (< 6 months) are mortality risk factors. Conclusions: Over a thousand KT have suffered Covid-19 in Spain with a high mortality rate in the first and second waves, mainly related with age, pneumonia and recent transplantation. The interaction between age and time after transplant has to be considered when selecting recipients in the Covid-19 pandemic.