key: cord-0890795-s2hqm6jt
authors: Lambert, David
title: Opioids and the COVID-19 pandemic: does chronic opioid use or misuse increase clinical vulnerability?
date: 2020-07-19
journal: Br J Anaesth
DOI: 10.1016/j.bja.2020.07.004
sha: f7382e1a8b96d75cb66b8895f41562109a7b4192
doc_id: 890795
cord_uid: s2hqm6jt

nan

or 'opioid crisis' [1] . According to a UK Office for National Statistics report in 2019 [2] there were 139,845 people in contact with drug services during the 2018/19 period; some of these will be opioid dependent but for many this will not be a single substance misuse.

Moreover, a Public Health England (PHE) report suggests 540,000 patients (retrospective) were continuously prescribed opioids for three years [3] , and some of these may be opioid dependent. It is possible that some patients in the PHE report may have also made contact with drug services. Patients presenting to substance misuse services are likely to be using multiple substances so purist ascription of effect to opioid alone is problematic.

The current COVID-19 pandemic and 'opioid epidemic' or dare I say pandemic have clearly intersected. There is an excellent, thought-provoking opinion piece on this by Becker and Fiellin [4] . The thrust of several papers on opioids and COVID-19 and the main narrative revolves around opioid prescribing, access to opioids and sociological considerations [e.g., [5] [6] . What about side effects of opioids in COVID infection? Is the opioid epidemic fuelling the COVID-19 pandemic ?

As we know opioids depress respiratory drive [7] and long-term use is immunosuppressive, [8] although direct clinical trial evidence for the latter is lacking [9] . That said some of the seminal early work showing opioid immunosuppression is based on data showing increased infections in addicts [10] . COVID infection is more likely to produce adverse outcomes in immunosuppressed patients, and this is part of the scientific evidence for shielding in this patient group. The respiratory effects of COVID-19 infection are known only too well to anaesthetists and intensivists, and ventilation of acutely unwell patients has been the mainstay of treatment and of ICU workload. Opioids may be required for pain management in COVID-19 patients, [11] and paradoxically opioids have been suggested in COVID-19 palliative care for patients experiencing the sensation of suffocation [12] .

In those using opioids chronically or misusing opioids, where immune depression and a propensity to respiratory depression is likely, COVID-19 infection may be all the more deadly. At the time of writing I am not aware of any published clinical data to support this prediction although Shanthanna and colleagues [13] , suggest that patients with chronic pain taking opioids might be more susceptible to COVID-19. Individuals who are opioid dependent also present with a range of additional co-morbidities, social deprivation and homelessness. Whilst not suggesting these are a direct consequence of opioid misuse they may be linked and combining to a major public health issue. With respect to COVID-19 protection, the UK Government defines a category of clinically vulnerable people where those with 'mild to moderate respiratory disease' and those with a 'weakened immune system as the result of certain conditions or medicines they are taking' are advised to take extra care [14] . Surely those using chronic opioids therapeutically or those misusing opioids should be included in the clinically vulnerable group?

The good, the bad, and the ugly: the many faces of opioids

When Epidemics Collide: Coronavirus Disease 2019 (COVID-19) and the Opioid Crisis

COVID-19 and addiction

Opioid Use Disorder and COVID-19: Crashing of the Crises

Opioid-induced respiratory depression in humans: a review of pharmacokinetic-pharmacodynamic modelling of reversal

Opioids and immune modulation: more questions than answers

Opioids and the immune system -friend or foe

Infections resulting from narcotic addiction; report of 102 cases

Chronic pain after COVID-19: implications for rehabilitation

Relieving the sensation of suffocation in patients dying with COVID-19. Tidsskr Nor Legeforen

Caring for patients with pain during the COVID-19 pandemic: consensus recommendations from an international expert panel