A prospective, longitudinal study found that most patients with COVID-19 disorders of consciousness (COVID-DoC) regained consciousness. These findings were published in Neurology.
Neurologic manifestations have been observed among up to 20% of patients with COVID-19. These patients commonly experience prolonged infection and outcomes remain unknown. The researchers asserted that DoC has presented as a unique challenge as patients are unable to communicate and recovery remains uncertain, causing clinicians and families to make difficult decisions about continuing or stopping life-sustaining treatment in the absence of robust clinical data.
The objective of the current study was to characterize the long-term recovery from COVID-DoC and evaluate its brain connectivity profile.
All patients (n=12) admitted or transferred to the intensive care unit (ICU) at Massachusetts General Hospital with COVID-DoC between July 2020 and March 2021 were included in this study. Disease features and clinical outcomes were compared with age-matched patients in the ICU with COVID-19 but no DoC (n=12) and neuroimaging data were compared with data from healthy controls individuals.
Patients admitted to the ICU with COVID-DoC were aged median 63.5 (interquartile range [IQR], 55-76.3) years and 42% were men. At admission to the ICU, they were in a vegetative state (67%), were comatose (17%), or minimally conscious (17%). Most had comorbidities of hypertension (92%), obesity (67%), diabetes (67%), and hyperlipidemia (58%). This patient population remained hospitalized for a median 49.5 (IQR, 36.8-62) days and all were intubated.
The patients admitted to the ICU with COVID-19 and no DoC had similar comorbidities and disease severity.
Patients with DoC remained under intravenous sedation longer than control individuals (t, 3.65; P <.005).
Excluding the patient who died before MRI, the remaining 11 patients with DoC recovered consciousness between 0 and 25 (median, 7) days after cessation of continuous sedation. Patients were discharged to an inpatient rehabilitation facility (n=6), a long-term acute care facility (n=2), or died (n=4).
Compared with healthy control individuals, the COVID-DoC population had less positive intra-network connectivity within the default mode network (F, 3.88; P <.001) and less negative intra-network connectivity between default mode network and salience network (F, 2.86; P <.01). In addition, COVID-DoC associated with reduced whole brain (F, 9.06; P <1´10-8) and brainstem (F, 4.27; P <.001) fractional anisotropy. All findings remained significant after Bonferroni correction.
This study found that patients with DoC who survived severe COVID-19 were likely to regain consciousness, however, rates of disability remained high immediately following hospital discharge. In addition, COVID-DoC was associated with loss of functional and structural brain connectivity, likely caused by brain injury.
This study was limited by power, despite being the largest study of COVID-DoC to date.
The researchers concluded that although future research is necessary, “these prospective findings inform the prognosis and pathophysiology of COVID-DoC.”
Fischer D, Snider SB, Barra ME, et al. Disorders of Consciousness Associated With COVID-19: A Prospective, Multimodal Study of Recovery and Brain Connectivity. Neurology. Published online December 3, 2021. doi:10.1212/WNL.0000000000013067