Hyperthyroid radioiodine therapy in the time of COVID-19: easy does it.

The COVID-19 pandemic continues to disrupt clinical services, with many hospitals endeavouring to resume routine work, mitigate viral transmission and prepare for the complexities of COVID-19 during annual winter pressures. In radiology and nuclear medicine, a large amount of recommendations, guidance and changes to legislation have been published to aid services to both react to the initial COVID-19 outbreak and to adjust operational procedures to minimise COVID-19 transmission [1,2]. Ideally, this would lead to a nationally harmonious and synchronised response to service resumption and access, for the benefit of patients in all areas of the country.

However, as the pandemic transitioned from country-wide outbreaks (such as the scale observed in most European countries in March/April 2020) to more local flare-ups and endemic infections, more localised responses are becoming evident in the resumption of services. Indeed, different response effects have been noted in a recent international survey that assessed changes across 220 nuclear medicine departments [3].

Many nuclear medicine services have resumed under ‘new normal conditions,’ utilising amended standard operating procedures, patient pathways and COVID-19 infection control practices (e.g. the British Nuclear Medicine Society COVID-19 recovery phase guidance: ). However, the path to recovering radioiodine therapy (RAIT) services for hyperthyroidism has been less clear. This is possibly due to hyperthyroid patients being considered as at a lower risk of harm than oncology patients, and because of concerns regarding the potential radiation exposure to healthcare staff should RAIT patients become infected with COVID-19 and require hospital admission and close care [2].

To better understand the approaches taken, or being considered, to reintroducing this service, we instigated a cross-sectional survey of the resumption of hyperthyroid RAIT as it stands in the UK in the autumn of 2020. The survey was circulated on the Institute of Physics and Engineering in Medicine’s nuclear medicine community of interest and the medical physics joint information systems committee mail base. Responses were received from 19 centres in England, Wales and Scotland from 28 August to 15 October 2020. Here, we present the survey findings and discuss the results.

Survey questions and responses

Is your thyrotoxicosis service still closed? Are you planning to reopen? If so, when?

Ten of the 19 respondents (53%) were yet to reopen. Seven of the ten centres yet to reopen were clarifying plans to restart their service by the end of October, whereas the remaining three centres yet to restart RAIT were awaiting further guidance on how to proceed or provided no further details.

Have you reopened your service? If so, when?

Nine of the 19 responding centres (47%) indicated that they had restarted treatments. One centre reopened in June, whereas three reopened in July, three in August and one in September. One centre did not detail when they reopened.

If you are planning to reopen or have reopened, are you using or planning to use any social restrictions for patients before or after treatment that you would not have advised prior to COVID-19? If so, could you provide details (e.g. pre/post-treatment, how long for, how severe; e.g. full self-isolation as per government advice, a subset of those measures, patient only, whole household)?

The majority of centres (15/19; 79%) required, or planning to introduce, a period of patient self-isolation prior to treatment. Significant variation in both the severity and duration of these pretreatment restrictions was reported (Table 1).

Table 1

The patient social restrictions prior to RAIT detailed by the responding centres

Number of respondents	Percentage of respondents (%)	Pre-RAIT precautions planned/being used
6	32	14 days of patient selfisolation
2	11	14 days of patient strict social distancing
1	5	14 days household isolation, or patient shielding within the home where this was impractical
1	5	10 days household isolation, or patient shielding within the home where this was impractical
1	5	7 days household isolation, or patient shielding within the home where this was impractical
1	5	7 days of patient selfisolation
1	5	5 days of patient selfisolation
1	5	3 days of patient shielding
1	5	Planning on advising a period of restriction, details to be confirmed
2	11	No current restrictions (one centre detailed being prepared to escalate should low local case numbers rise)
2	11	No information provided

Eight (42%) of the responding centres were also utilising increased periods of patient social restriction after treatment. Of the eight centres using additional post-therapy isolation periods, five stated that 14 days of patient self-isolation after treatment was being advised, whereas three detailed the use of 14 days of total household isolation (or patient shielding/strict social distancing within the home where whole household isolation was not possible). Six of all the respondents (32%) were not using additional post-therapy social restrictions, whereas five (26%) provided no further information on this issue.

Two of the survey respondents (11%) provided additional information as to preparations they had made should a RAIT patient be admitted with COVID-19. One centre indicated that patients are given a letter to present should they be admitted within 2 weeks of RAIT, with instructions to contact the nuclear medicine department for a patient-specific risk assessment. The other centre stated that guidelines for the emergency care of radioactive patients had been provided to departments along the emergency patient pathway, which included out of hours radiation protection advice and nuclear medicine contact details for a patient-specific risk assessment.

If you are planning to reopen or have reopened, are you planning on or currently asking patients to take a COVID-19 swab test in the days prior to treatment? If so, what cut off on how many days before treatment are you working/planning to work to?

In total 13 of the 19 responding centres (68%) stated that they were requesting patients to undergo a COVID-19 swab test prior to treatment (6 of the 13 centres had reopened their RAIT service and were using testing, whereas 7 of the centres were planning on utilising testing when they had reinstated their service). Of these 13 centres, 11 specified testing at 3 days or 72 h prior to treatment, whereas the remainder were testing up to 48 h prior to treatment.

Three centres (16% of all respondents) detailed that they were not using/planning to use COVID-19 testing. Two of these centres reported that this was either due to concerns about false-negative results, or because it was felt that the use of 14 days of patient self-isolation before treatment was adequate. The remaining three centres (16% of all respondents) were either still planning their service recovery and were yet to reach a decision regarding COVID-19 testing, or provided no further information.

If you are planning to reopen or have reopened, are you planning to treat/currently treating all patients as referrals come in, or only those that are clinically urgent and likely to suffer harm without I131 therapy, deferring less urgent patients?

Four of the 19 respondents (21%) detailed that either only urgent patients will be treated, that each patient will be assessed for eligibility, or that they will not be accepting patients deemed to be a high COVID-19 risk. Although 11 centres (58%) indicated that they planned to treat all patients in their backlog, 4 were treating (or planning to treat) their patients in order of clinical priority as defined by their endocrinology practitioner(s). The remaining four respondents (21%) either provided no information on their approach to patient prioritisation or inclusion for RAIT, or were yet to confirm their plans.

Discussion

The responses to the survey questions demonstrated a varied approach to reintroducing and delivering RAIT during the COVID-19 pandemic. With 15 out of the 19 respondents (79%) instituting some form of social restriction prior to treatment, the risk of administering RAIT to a patient with presymptomatic COVID-19 who may then require COVID-19 treatment was a significant concern. Even though the use of post-RAIT social restrictions to keep radiation exposure to patient’s family members and members of the public as low as reasonably practicable [4] can be seen as complementary to COVID-19 social distancing advice, eight (42%) of the responding centres were also advising, or planning to advise, additional social restrictions after treatment due to concerns around patients contracting COVID-19 after RAIT.

While published guidelines, experiences and recommendations provide a general and broad method to safely alter practice to minimise COVID-19 transmission, overriding decisions will most likely continue to be made at a local level. This is seen in the survey responses, in the variety of approaches detailed in Table 1, the varied use of COVID-19 testing prior to treatment, the range of post-treatment social restriction advice and the level of contingency planning should a RAIT patient require care for COVID-19.

In addition to radiation protection concerns regarding the care of a COVID-19 positive RAIT patient, the data collected in this survey also demonstrates that many centres have built up a backlog of RAIT referrals, while clinically nonurgent services were closed. The addition of COVID-19 infection control measures [2] has also reduced the number of patients that can be treated to below previous patient flow norms, and some centres are not yet operationally ready to deliver treatments to all patients. This has led to some centres expressing that the resumption of services had not reached a level where all referrals could be accepted.

Although there is no ‘right answer’ on how to proceed with the resumption of hyperthyroid RAIT, centres may modify their requirements following the phases of nationwide and local disease prevalence, as well as following organisational level directions. Local decisions are being made to try to balance the risk of potentially caring for a COVID-19 positive, radioactive patient with the collective benefit of providing RAIT treatments to the hyperthyroid population. However, it remains to be seen how the use of significant social restrictions before and after therapy affects patient consent. This may be a particular problem for medium- to high-risk patients who do not have access to significant sick pay or work with children. These patients may be required to take up to 41 days out of the workplace using the longest pre-therapy isolation period found in this survey and normal post-therapy restrictions for contact with young children [5]. Patients with a young family may also find it difficult to maintain self-isolation in the home for such lengthy time periods.

Many logistical changes are taking place in the delivery of healthcare due to the ongoing pandemic, for example, the emerging role of telemedicine [6], the employment of artificial intelligence in the stratification of patients [7] and in the delivery of clinical imaging research [8]. As COVID-19 is now well established in the population and is likely to be a challenge for the foreseeable future, more novel approaches to delivering therapeutic nuclear medicine services may be required going forward. While this editorial primarily seeks to share the approaches being taken by the responding centres to restart and deliver RAIT services for hyperthyroidism, it seems that there is also space for innovation in the delivery of this treatment during the pandemic. One potential approach could be a patient-specific COVID-19 risk assessment for RAIT. This could consider local COVID-19 infection rates, the age of the patient, the number and type of contacts they have, personal protective equipment use and any other preconditions that may increase the risk of admission after RAIT, rather than the application of significant restriction periods before and after treatment. Such an approach may provide a useful tool to control the COVID-19 risk in a patient-centered manner and more confidently deliver RAIT services while the risk of COVID-19-related admissions is present.

Acknowledgments

Authors are grateful to all the responders of this survey for their participation and support. Bill Thomson and Bruno Rojas Fisher are also thanked for useful discussions. J.O.D. is employed by Siemen Medical Solutions, this work was not financially sponsored or supported by Siemens Medical Solutions.

Conflicts of interest

There are no conflicts of interest.