Prevalence of e-cigarette users in New South Wales

Electronic cigarette (e-cigarette) use has grown rapidly in parts of the world, the United Kingdom and United States in particular.1,2 In Australia, evidence is lacking regarding how widely e-cigarettes are used, for what purpose and by whom. There is vigorous debate over the harms and benefits of e-cigarettes, including whether they are the next big thing in smoking cessation or whether they will act as a gateway to tobacco smoking.3,4 The first step towards being able to answer these important questions is to understand the profile and prevalence of e-cigarette users.

While information on the prevalence of e-cigarette use among smokers in Australia has been publicly reported,4 to our knowledge, there is no published information on population-level prevalence rates of e-cigarette use in Australia and no indication of whether we are seeing an increase from year to year comparable with what has been seen overseas. The 2014 New South Wales Population Health Survey provides insights into e-cigarette use in the state and a baseline from which future changes in use can be measured in the general population.

The telephone-based survey, administered by the NSW Ministry of Health, captured responses to a question on e-cigarette use from 12 502 respondents aged 18 years or older, using a dual frame (mobile phone and landline) sampling strategy to account for declines in landline ownership. Data collection and weighting methods for the survey have been described elsewhere.5 Current e-cigarette use was defined as respondents who used e-cigarettes on a daily or occasional basis, which may include users who were trialling the devices when surveyed.1 Design-adjusted prevalence estimates, relative risks (RRs) and 95% confidence intervals were calculated using SAS version 9.4 (SAS Institute).

We found the prevalence of current e-cigarette users in NSW was 1.3% (95% CI, 0.9–1.7), while 8.4% (95% CI, 7.5–9.3) of the population was estimated to have tried an e-cigarette (Box). Current smokers were 7.5 times more likely to be current e-cigarette users than non-smokers (RR, 7.5; 95% CI, 4.2–13.7), while males (RR, 1.2; 95% CI, 0.7–2.2) and people aged 18–44 years (RR, 1.8; 95% CI, 1.0–3.3) were more likely to have ever tried an e-cigarette compared with females and people aged 45 years or older, respectively. We estimate that about 78 000 people are current users of e-cigarettes in NSW. Current use of e-cigarettes is relatively low compared with other countries, such as the US and the UK.1,2 While increases in e-cigarette use were observed in the US and the UK, it is unclear whether NSW will see a similar growth pattern. The NSW Ministry of Health will continue to monitor the use of e-cigarettes in the state.