Electronic cigarette use and implications for tobacco cessation

Clinical practice guidelines for treating tobacco use and dependence were most recently updated in 2008 and urge clinicians to ask patients about their current smoking status and to advise current smokers to quit.

For patients who qualify, seven first-line pharmacologic therapies are recommended to aid in quit attempts:

• five delivery systems of nicotine replacement therapy (NRT) including the patch, gum, lozenge, nasal spray (Nicotrol NS®) and the oral inhaler (Nicotrol®);

• Zyban® (bupropion SR); and

• Chantix® (varenicline).

Using six month abstinence as an outcome, Chantix was found to triple the odds of long term abstinence while all other first-line therapies doubled or were close to doubling the odds of long term abstinence, all in comparison to placebo. Many trials that evaluate these therapies also provide counseling and behavioral interventions so some of this benefit is drawn from these co-interventions. Each therapy is associated with unique adverse effects ranging from local skin irritation from patches to psychiatric and cardiovascular risks with Chantix.

There has been increasing awareness and use of electronic cigarettes (e-cigarettes) in the United States over the recent years. National survey data suggests that from 2010 to 2011, adult awareness of e-cigarettes increased from 40% to 57.9% while ever-use increased from between 2% and 3% to 6.2%.

The recent uptake of e-cigarettes in addition to encouragement from Attorneys General across the country has prompted the Food and Drug Administration (FDA) to take measures to propose expansion of what the current definition of “tobacco product” is so that it would be inclusive of electronic cigarettes. Tobacco products currently under FDA regulation include cigarettes, cigarette tobacco, roll-your-own tobacco, and smokeless tobacco. Once the proposal is finalized, the same regulations in Chapter IX of the Federal Food, Drug and Cosmetic Act that these tobacco products are held to will apply automatically to electronic cigarettes.

Until this year, little was known about e-cigarette efficacy and safety as a smoking cessation aid. Two recent trials have provided some information to fill this gap.

The first trial evaluated 300 healthy, middle-aged smokers who smoked on average 20 cigarettes per day for 20 years and were unwilling to quit at this time. Patients were randomized into three groups and treated for 12 weeks: two nicotine e-cigarette arms or placebo e-cigarettes. Although there were significant declines in actual cigarettes smoked per day in all three groups at weeks 12 and 52, there were no differences between the three groups. At both time points, there were a significantly greater number of subjects who quit smoking in the nicotine e-cigarette groups versus the placebo e-cigarette group (14% vs. 4% at 12 weeks; 11% vs. 4% at 52 weeks).

Side effects associated with smoking cessation or withdrawal such as hunger, insomnia, irritability, anxiety, and depression were reported in 6.5%, 4%, 3.5%, 3% and 2% of subjects respectively.

A second trial sought to evaluate e-cigarettes as a smoking cessation aid in comparison to nicotine patches. A total of 657 middle-aged smokers, smoking on average 18 cigarettes per day for 15 years were randomized to receive nicotine e-cigarettes, nicotine patches, or placebo e-cigarettes.

Unfortunately, the abstinence rates in the trial were much lower than anticipated which led the trial to be underpowered to statistically determine if e-cigarettes were superior to nicotine patches based on the primary outcome of continuous abstinence at six months. However, nicotine e-cigarette users reduced the mean number of cigarettes smoked per day by two more than nicotine patch users at six months and a greater proportion reduced their daily cigarette smoking by more than 50% from baseline to six months compared to nicotine patch users.

The total number of adverse events was higher in the nicotine e-cigarette group compared to the nicotine patch group although the difference was not statistically significant and the authors concluded that there was no association found with study product. Based on the current literature it appears as though e-cigarettes help smokers decrease the number of cigarettes they smoke per day without any concerning risks when used for up to 12 weeks. However, how e-cigarettes compare to approved smoking cessation therapies is still unknown and will be a subject for future research.