Prognostic Indicators and Outcomes of Hospitalised COVID-19 Patients with Neurological Disease: A Systematic Review and Individual Patient Data Meta-Analysis

Background: Neurological COVID-19 disease has been reported widely, but often without using standard case definitions or detailed diagnostic work up. Several meta-analyses, based on such reports, describe the neurological diagnoses but give little information on outcomes and risk factors. Methods: We conducted an individual patient data meta-analysis of hospitalised patients with neurological COVID-19 disease, using standard case definitions. We invited authors of studies from the first pandemic wave, plus clinicians in the Global COVID-Neuro Network with unpublished data, to contribute, and extracted aggregate data from published reports. We analysed features associated with poor outcome (moderate to severe sequelae or death, 3-6, on the modified Rankin scale) using multivariable models. Findings: We identified 381 studies (31 unpublished) describing 4443 patients with COVID-19 and neurological disease: 83 of these provided IPD for 1979 (45%) patients. Encephalopathy (978 [49%]) and cerebrovascular events (506 [26%]), were the most common diagnoses in the IPD database and aggregate data. Respiratory and systemic symptoms preceded neurological features in 93% of patients; one third developed neurological disease after hospital admission. A poor outcome was more common in patients with cerebrovascular events (76% [95% CI 67-82]), than encephalopathy (54% [42-65]). Intensive care use was high (38% [35-41] overall), and also greater in the cerebrovascular patients. In the cerebrovascular, but not encephalopathic patients, risk factors for poor outcome included breathlessness on admission and elevated D-Dimer. Overall, 30-day mortality was 30% (27-32). The hazard of death was reduced for patients in the WHO European region, but increased in low- and lower-middle-income countries. Interpretation: Neurological COVID-19 disease poses a considerable burden in terms of disease outcomes and use of hospital resources. The different risk factors for encephalopathy and stroke suggest different disease mechanisms which may be amenable to intervention, especially in those who develop neurological symptoms after hospital admission. Funding This study was funded by the UK Medical Research Council’s Global Effort on COVID-19 Programme (MR/V033441/1); UK National Institute for Health Research (NIHR)-funded Global Health Research Group on Acute Brain Infections (17/63/110); and the NIHR Health Protection Research Unit in Emerging and Zoonotic Infections (NIHR200907), at University of Liverpool in partnership with Public Health England (PHE), in collaboration with Liverpool School of Tropical Medicine and the University of Oxford (Grant Nos. IS-HPU-1112-10117 and NIHR200907). Declaration of Interests: BS reports a grant from UKRI/DHSC Global Effort on COVID-19 Research (Medical Research Council) and non-financial support from UK National Institute for Health Research Global Health Research Group on Brain Infections. SL and TS are supported by a grant from the EU Zika Preparedness Latin American Network consortium (ZikaPLAN). ZikaPLAN has received funding from the EU's Horizon 2020 research and innovation programme under grant agreement number 734584. LCG reports non-financial support from Pfizer, non-financial support from Gilead. LB reports grants from GlaxoSmithKline, Research England and Wellcome Trust. AMBM reports grants from Conselho Nacional de Desenvolvimento Cientifico e Tecnologico CNPq/Brazil, and Sao Paulo Research Foundation FAPESP/Brazil. AP reports personal fees from ZAMBON, UCB , BIOMARIN, and ABBvie pharma. TS was an adviser to the GlaxoSmithKline Ebola Vaccine programme, chaired a Siemens Diagnostics clinical advisory board, and advises the WHO Brain Health Unit Forum on Neurology and COVID-19; TS has also previously filed a patent for a test for bacterial meningitis based on a blood test (GB 1606537.7, April 14, 2016), and has grants from the UK Medical Research Council and National Institute for Health Research. All other authors declare no conflict of interest