Persistent cognitive impairment is increasingly recognised as a major component of post-acute sequelae of SARS-CoV-2 infection (PASC) 1. It is distinct from the cognitive sequelae of acute COVID-19 and other neurological disorders such as stroke and encephalitis. Estimates of the prevalence of cognitive impairment in PASC vary from 20 to 75% (1–3). Cognitive impairment in PASC is characterised primarily by impairments in executive function, attention, speed of information processing (4), and working memory (3, 5–7), with the impairment independent of age, gender, or prior medical conditions (8). The notion that cognitive impairment is a major and distinct aspect of PASC is reinforced by observations that the occurrence of cognitive impairment is unrelated to prior ITU admission and is not associated with fatigue, depression, or severity of acute inflammation 9. These studies also show that cognitive impairment as part of PASC occurs even after milder infections, independent of comorbidities or stress reactions. The potential negative impact on working-age individuals, and in turn personal and national economies, is underscored by a UK study showing that dementia-range cognitive impairment was found in 26% of affected individuals, half of whom were working-age 10.
The loss in cognitive ability has major consequences for affected people, their families, and the wider economy given the problems caused regarding return to work. Moreover, its impact has been observed on overall well-being and quality of life (9–11), and regulation of emotions – symptoms of anxiety, depression, and mood swings(12). Reduction in occupational and social activities like participating in hobbies, engaging in physical activities, and reduction in social interactions, have been reported as potentially leading to social isolation (13), with an overall reduced ability to carry out daily tasks (14).
However, despite the major morbidity associated with this new disorder, to date, there are no evidence-based treatments for PASC cognitive impairment. Therefore, this represents a major unmet need in the management of PASC and there is an imperative to identify and test potential treatment options.
1.1. Cognitive rehabilitation
Cognitive rehabilitation represents one possible treatment. There is an extensive history of cognitive rehabilitation being successfully applied to other acquired cognitive disorders, notably, traumatic brain injury (TBI) and multiple sclerosis (MS) (15), whose profiles of cognitive impairment share similarities with that observed in PASC (16). Cognitive rehabilitation has helped people with TBI to improve their attention, learning, and memory, and to develop compensatory activities. This has led to better performance in activities of daily living (17, 18). Techniques like goal management training and external cueing can lead to improvement in executive functioning, better organisation and planning and long-term functional gains in real-world tasks (19). In multiple sclerosis, cognitive impairment often involves reduced processing speed, memory, and executive dysfunctions that negatively impact the quality of life (20). Cognitive rehabilitation using self-generation, repetition strategies, and functional aids have been found to improve memory, processing speed, and daily task performance in people with MS (21).
1.2. Telehealth-delivered cognitive rehabilitation
While traditional methods have involved lengthy face-to-face sessions, the requirement for social distancing during the COVID-19 pandemic necessitated a wholesale pivot towards remote provision of clinical care (22). However, the potential utility of remotely applied cognitive rehabilitation in PASC is supported by precedents for this approach, with telehealth platforms having previously been used to deliver cognitive interventions in dementia(23) and MS (24). While telehealth introduces some technical and logistical considerations (25), it confers notable advantages over traditional approaches that are especially relevant for this clinical population. Remote application helps remove barriers of geography and mobility that can limit access to in-person services. It has shown to be also a cost-effective way to deliver therapies and have a positive impact on quality of life(26) across patient and demographic groups (27). Given that COVID-19 in the UK disproportionately affected ethnic minority populations (28), historically disadvantaged in access to health services, such issues are of particular salience. Furthermore, the fatigue that represents a major symptom of PASC might make it difficult for affected individuals to complete traditional face-to-face cognitive rehabilitation sessions, potentially compromising the treatment effect. Remote delivery of the treatment in shorter segments mitigates this risk in a way that has advantages both for the provider and the recipient of treatment.
This manuscript focuses on the study protocol for an RCT to test the effectiveness and cost-effectiveness of this rehabilitation programme to improve personally identified functional outcomes by people living with post-COVID cognitive impairment.