Prophylactic heparin and risk of orotracheal intubation or death in patients with mild or moderate COVID-19 pneumonia
Authors: Vergori Alessandra , Lorenzini Patrizia , Cozzi-Lepri Alessandro , Donno Davide Roberto , Gualano Gina , Nicastri Emanuele , Iacomi Fabio , Marchioni Luisa , Campioni Paolo , Schininà Vincenzo , Cicalini Stefania , Agrati Chiara , Capobianchi Maria Rosaria , Girardi Enrico , Ippolito Giuseppe , Vaia Francesco , Petrosillo Nicola , Antinori Andrea , Taglietti Fabrizio ,   The ReCOVeRI Study Group, Abbonizio Maria Alessandra , Abdeddaim Amina , Agostini Elisabetta , Albarello Fabrizio , Amadei Gioia , Amendola Alessandra , Antonica Maria Assunta , Antonini Mario , Bartoli Tommaso Ascoli , Baldini Francesco , Barbaro Raffaella , Bartolini Barbara , Bellagamba Rita , Benigni Martina , Bevilacqua Nazario , Biava Gianluigi , Bibas Michele , Bordi Licia , Bordoni Veronica , Boumis Evangelo , Branca Marta , Buonomo Rosanna , Busso Donatella , Camici Marta , Canichella Flaminia , Capobianchi Maria Rosaria , Capone Alessandro , Caporale Cinzia , Caraffa Emanuela , Caravella Ilaria , Carletti Fabrizio , Castilletti Concetta , Cataldo Adriana , Cerilli Stefano , Cerva Carlotta , Chiappini Roberta , Chinello Pierangelo , Cianfarani Maria Assunta , Ciaralli Carmine , Cimaglia Claudia , Cinicola Nicola , Ciotti Veronica , Colavita Francesca , Corpolongo Angela , Cristofaro Massimo , Curiale Salvatore , D’Abramo Alessandra , Dantimi Cristina , De Angelis Alessia , De Angelis Giada , De Palo Maria Grazia , De Zottis Federico , Di Bari Virginia , Di Lorenzo Rachele , Di Stefano Federica , D’Offizi Gianpiero , Evangelista Francesca , Faraglia Francesca , Farina Anna , Ferraro Federica , Fiorentini Lorena , Frustaci Andrea , Fusetti Matteo , Fusto Marisa , Galati Vincenzo , Gagliardini Roberta , Gallì Paola , Garotto Gabriele , Gaviano Ilaria , Tekle Saba Gebremeskel , Giancola Maria Letizia , Giansante Filippo , Giombini Emanuela , Granata Guido , Greci Maria Cristina , Grilli Elisabetta , Grisetti Susanna , Iaconi Marta , Iannicelli Giuseppina , Inversi Carlo , Lalle Eleonora , Lamanna Maria Elena , Lanini Simone , Lapa Daniele , Lepore Luciana , Libertone Raffaella , Lionetti Raffaella , Liuzzi Giuseppina , Loiacono Laura , Lucia Andrea , Lufrani Franco , Macchione Manuela , Maffongelli Gaetano , Marani Alessandra , Mariano Andrea , Marini Maria Cristina , Maritti Micaela , Mastrobattista Annelisa , Mastrorosa Ilaria , Matusali Giulia , Mazzotta Valentina , Mencarini Paola , Meschi Silvia , Messina Francesco , Micarelli Sibiana , Mogavero Giulia , Mondi Annalisa , Montalbano Marzia , Montaldo Chiara , Mosti Silvia , Murachelli Silvia , Musso Maria , Nardi Michela , Navarra Assunta , Nocioni Martina , Noto Pasquale , Noto Roberto , Oliva Alessandra , Onnis Ilaria , Ottou Sandrine , Palazzolo Claudia , Pallini Emanuele , Palmieri Fabrizio , Palombi Giulio , Pareo Carlo , Passeri Virgilio , Pelliccioni Federico , Penna Giovanna , Petrecchia Antonella , Petrone Ada , Pianura Elisa , Pinnetti Carmela , Pisciotta Maria , Piselli Pierluca , Pittalis Silvia , Pontarelli Agostina , Proietti Costanza , Puro Vincenzo , Ramazzini Paolo Migliorisi , Rianda Alessia , Rinonapoli Gabriele , Rosati Silvia , Rubino Dorotea , Rueca Martina , Ruggeri Alberto , Sacchi Alessandra , Sampaolesi Alessandro , Sanasi Francesco , Santagata Carmen , Scarabello Alessandra , Scarcia Silvana , Scognamiglio Paola , Scorzolini Laura , Stazi Giulia , Strano Giacomo , Taibi Chiara , Taloni Giorgia , Nardi Tetaj , Tonnarini Roberto , Topino Simone , Tozzi Martina , Vairo Francesco , Valli Maria Beatrice , Vincenzi Laura , Visco-Comandini Ubaldo , Vita Serena , Vittozzi Pietro , Zaccarelli Mauro , Zanetti Antonella , Zito Sara 
Published: May 2021

Prophylactic low molecular weight heparin (pLMWH) is currently recommended in COVID-19 to reduce the risk of coagulopathy. The aim of this study was to evaluate whether the antinflammatory effects of pLMWH could translate in lower rate of clinical progression in patients with COVID-19 pneumonia. Patients admitted to a COVID-hospital in Rome with SARS-CoV-2 infection and mild/moderate pneumonia were retrospectively evaluated. The primary endpoint was the time from hospital admission to orotracheal intubation/death (OTI/death). A total of 449 patients were included: 39% female, median age 63 (IQR, 50–77) years. The estimated probability of OTI/death for patients receiving pLMWH was: 9.5% (95% CI 3.2–26.4) by day 20 in those not receiving pLMWH vs. 10.4% (6.7–15.9) in those exposed to pLMWH; p-value = 0.144. This risk associated with the use of pLMWH appeared to vary by PaO2/FiO2 ratio: aHR 1.40 (95% CI 0.51–3.79) for patients with an admission PaO2/FiO2 ≤ 300 mmHg and 0.27 (0.03–2.18) for those with PaO2/FiO2 > 300 mmHg; p-value at interaction test 0.16. pLMWH does not seem to reduce the risk of OTI/death mild/moderate COVID-19 pneumonia, especially when respiratory function had already significantly deteriorated. Data from clinical trials comparing the effect of prophylactic vs. therapeutic dosage of LMWH at various stages of COVID-19 disease are needed.