Incidence and prevalence of coma in the UK and the USA

Daniel Kondziella; Moshgan Amiri; Marwan H Othman; Ettore Beghi; Yelena G Bodien; Giuseppe Citerio; Joseph T Giacino; Stephan A Mayer; Thomas N Lawson; David K Menon; Verena Rass; Tarek Sharshar; Robert D Stevens; Lorenzo Tinti; Paul Vespa; Molly McNett; Chethan P Venkatasubba Rao; Raimund Helbok; Curing Coma Campaign Collaborators

doi:10.1093/braincomms/fcac188

Incidence and prevalence of coma in the UK and the USA

Brain Commun. 2022 Sep 1;4(5):fcac188. doi: 10.1093/braincomms/fcac188. eCollection 2022.

Authors

Daniel Kondziella^{1

2}, Moshgan Amiri¹, Marwan H Othman¹, Ettore Beghi³, Yelena G Bodien^{4

5}, Giuseppe Citerio^{6

7}, Joseph T Giacino⁴, Stephan A Mayer⁸, Thomas N Lawson⁹, David K Menon¹⁰, Verena Rass¹¹, Tarek Sharshar^{12

13}, Robert D Stevens^{14

15

16}, Lorenzo Tinti³, Paul Vespa^{17

18}, Molly McNett⁹, Chethan P Venkatasubba Rao¹⁹, Raimund Helbok¹¹; Curing Coma Campaign Collaborators

Collaborators

Curing Coma Campaign Collaborators:
Yama Akbari, Melanie Boly, Neha Dangayach, Brian Edlow, Brandon Foreman, Emily Gilmore, Flora M Hammond, J Claude Hemphill 3rd, Theresa Human, Lori Kennedy Madden, Shraddha Mainali, Geert Meyfroidt, Martin Monti, Risa Nakase-Richardson, Paul Nyquist, DaiWai Olson, Soojin Park, Jose Javier Provencio, Louis Puybasset, Aarti Sarwal, Lori Shutter, Briana Witherspoon, John Whyte, Wendy Ziai

Affiliations

¹ Department of Neurology, Rigshospitalet, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.
² Department of Clinical Medicine, University of Copenhagen, Copenhagen 2100, Denmark.
³ Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan 20156, Italy.
⁴ Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Harvard Medical School, Boston, MA 02115, USA.
⁵ Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
⁶ NeuroIntensive Care, ASST di Monza, Monza 20900, Italy.
⁷ School of Medicine and Surgery, Università Milano Bicocca, Milan 20100, Italy.
⁸ Department of Neurology, New York Medical College, Valhalla, NY 10595, USA.
⁹ College of Nursing, The Ohio State University, Columbus, OH 43210, USA.
¹⁰ Division of Anaesthesia, University of Cambridge, Cambridge CB2 2QQ, UK.
¹¹ Department of Neurology, Neuro-Intensive Care Unit, Medical University of Innsbruck, Innsbruck 6020, Austria.
¹² Neuro-anesthesiology and Intensive Care Medicine, Sainte-Anne Hospital, Paris-Descartes University, Paris 75006, France.
¹³ Experimental Neuropathology, Infection and Epidemiology Department, Institut Pasteur, Paris 75015, France.
¹⁴ Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
¹⁵ Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21218, USA.
¹⁶ Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore 21287, MD, USA.
¹⁷ Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
¹⁸ Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
¹⁹ Division of Vascular Neurology and Neurocritical Care, Baylor College of Medicine and CHI Baylor St Luke's Medical Center, Houston, TX 77030, USA.

Abstract

The epidemiology of coma is unknown because case ascertainment with traditional methods is difficult. Here, we used crowdsourcing methodology to estimate the incidence and prevalence of coma in the UK and the USA. We recruited UK and US laypeople (aged ≥18 years) who were nationally representative (i.e. matched for age, gender and ethnicity according to census data) of the UK and the USA, respectively, utilizing a crowdsourcing platform. We provided a description of coma and asked survey participants if they-'right now' or 'within the last year'-had a family member in coma. These participants (UK n = 994, USA n = 977) provided data on 30 387 family members (UK n = 14 124, USA n = 16 263). We found more coma cases in the USA (n = 47) than in the UK (n = 20; P = 0.009). We identified one coma case in the UK (0.007%, 95% confidence interval 0.00-0.04%) on the day of the survey and 19 new coma cases (0.13%, 95% confidence interval 0.08-0.21%) within the preceding year, resulting in an annual incidence of 135/100 000 (95% confidence interval 81-210) and a point prevalence of 7 cases per 100 000 population (95% confidence interval 0.18-39.44) in the UK. We identified five cases in the USA (0.031%, 95% confidence interval 0.01-0.07%) on the day of the survey and 42 new cases (0.26%, 95% confidence interval 0.19-0.35%) within the preceding year, resulting in an annual incidence of 258/100 000 (95% confidence interval 186-349) and a point prevalence of 31 cases per 100 000 population (95% confidence interval 9.98-71.73) in the USA. The five most common causes were stroke, medically induced coma, COVID-19, traumatic brain injury and cardiac arrest. To summarize, for the first time, we report incidence and prevalence estimates for coma across diagnosis types and settings in the UK and the USA using crowdsourcing methods. Coma may be more prevalent in the USA than in the UK, which requires further investigation. These data are urgently needed to expand the public health perspective on coma and disorders of consciousness.

Keywords: COVID-19; brain injury; cardiac arrest; coma; consciousness.