Harms

In the early phases of the study design, our funders panel and PPI work raised several concerns that EC devices provided free of charge to those presenting with substance use disorders or very little income might be sold, stolen or used for inhaling illicit street trade substances. Therefore, despite a well-intended act of offering an EC, this could invite several unintended consequences.

To systemically monitor risk and the occurrence of unintended consequences, we developed a checklist of questions that participants would be asked at each follow-up assessment. The questionnaire is based on our extensive PPI, with input from our expert and multidisciplinary team, our Trial Steering Group and those working in the third sector. These data, although recorded retrospectively, do not prevent the occurrence of these incidents. The rationale for the inclusion of this checklist was twofold: first, it was included so that we could capture the number of times these events occurred and, second, it was included to offer support if required.

The rationale for each question based on our PPI work is as follows:

1. Do you still have the electronic cigarette that we supplied? This question was asked to ascertain whether or not the participant was still in possession of the product that had been supplied to them as part of the study. It was raised during our PPI consultation work that adults who are not securely housed or sharing residences may easily lose their EC, have it stolen or sell it.
2. (If no) Since our last meeting has your electronic cigarette been lost, stolen, sold, exchanged? Here we are seeking to gather information as to what happened to the device. Understanding if people are retaining their EC can help with future planning for more definitive studies or service provision.
3. If yes, to any of the above, please provide details. This allowed free-text responses so that the participant could elaborate and give the study team more information related to the event. By collecting more detailed information, study teams can try to further mitigate risks such as theft and understand the nature of the event (e.g. coercive theft) surrounding the incidents.
4. Have you added any of the following to your electronic cigarette? A frequent concern when designing the study was that participants may use the EC for vaping substances other than e-liquid. Here we aim to capture if the EC is being used for vaping any other substances and which ones.
5. Have you used the electronic cigarette for any other purposes? To monitor unforeseen or unpredicted use, we were advised to include this question to capture a broad range of usage.
6. For you, does the experience of using an electronic cigarette have any other similarities to drug use (for example crack)? Although not common, in our scoping and PPI work, a small number of clients from homeless centres commented that, for them, use of a pen-like second-generation EC triggered memories of historic crack cocaine smoking owing to the device’s shape and the sensory aspect of inhalation.

The majority of the participants used the device as intended. Table 12 presents frequency and percentage data at each follow-up point.

Electronic cigarette, lost, stolen or exchanged

At the 24-week follow-up, 63% of participants still had the EC we provided. Across the follow-up period, there were only seven individual incidents of EC loss and six reported thefts, and nobody reported selling their device. However, one person reported exchanging their device at 4 weeks and three people gave their device away. Other reasons why people did not have their device was because they did not like the taste or the feel of it (n = 2) or reported accidentally leaving it elsewhere (n = 5); one person reported having it confiscated upon admission to hospital.

There was a high percentage of breakages; across the follow-up times, breakages were reported on average 25% of the time. The most common breakage reported was cracked glass tanks.

Adding other substances

There were two reports across the follow-up period of adding other substances not intended for vaping. At 24 weeks, one person reported adding THC and another CBD oil; however, these were added to other devices, not the devices that were provided in this study, suggesting that regular second-generation ECs as provided here may not be compatible with vaping other substances.

Use of the electronic cigarette for any other purpose

At all follow-up appointments, the majority of people said that they had not used their device for any other purpose. At 4 weeks, one person reported using it to mimic vaping without actually switching the device on (‘I put my lips on it’). There were no reports of unintentional use at 12 weeks. At the 24-week follow-up, one person reported using it as a back scratcher and attempted to use it to light a cigarette.

Similarities to drug use

The majority of participants reported no similarities to drug use experiences. However, two did. One participant noted at all three follow-up points that using the device was similar to crack use, and one other participant reported a similarity to smoking cannabis through a ‘bong’.