xBio 2014 ASPET Blogging: Incentives for Smoking Cessation

Smoking is bad for your health. Everyone knows that, right? While the number of smokers has steadily declined since 1965, 20% of adults in the United States were smokers in 2011. According to the Centers for Disease Control and Prevention (CDC), smoking is the leading cause of preventable disease and premature death with 480,000 deaths per year in the United States. That's 1 in 5 deaths. Let that sink in. It also accounts for 10% of all deaths worldwide. There are huge economic costs associated with smoking, to the tune of $300 billion per year in the US. Economic costs are calculated using direct health care costs as well as the cost of lost time from work due to smoking-related illness, premature death, and disability.

Figure 1: Cigarette smoking in the US has declined steadily since 1965 (Source)

Knowing all this, it becomes clear that reducing smoking is an important goal which goes beyond just, "it's an unhealthy life choice". Some people are able to quit cold turkey but nicotine has highly addictive properties and many struggle to abstain permanently. Currently available strategies for quitting include behavioral modification and pharmacological approaches.



Behavioral approaches include activities such as attending smoking cessation sessions, telephone support, one-on-one cognitive behavioral therapy, and incentive programs. Incentive programs can be highly effective, according to Dr. Stephen Higgins at the University of Vermont, but take experience to design. Dr. Higgins said the most effective programs use higher value incentives and regular contact to track abstinence and reward success.

Dr. Higgins' research focuses on a group whose background is associated with higher rates of smoking and for whom quitting can have a dramatic impact: pregnant women in lower socioeconomic classes. In an ongoing study in his clinic, 166 pregnant women were enrolled and randomly partitioned into two groups. Both groups received financial incentives in the form of vouchers exchangeable for retail items. In the control group, financial incentives were provided at regular intervals for continued participation and independent of smoking status. In the experimental group, participants received financial incentives only if they reported abstaining from smoking and that report was biochemically verified.  Smoking abstinence was monitored daily in the first week of quitting, then weekly, then every other week through the pregnancy.  Dr. Higgins said this regular monitoring schedule with material rewards for success is crucial and is where many programs go wrong.  The amount of financial incentives is also important. The control group received an average of $416 and the experimental group $460 over the course of the study, which was not a statistically significant difference.  The critical difference was that women in the experimental condition had to change their behavior in order to receive the reward.

At the birth of their child, the experimental group showed a higher rate of abstinence from smoking (35%) when compared with the control group (7%). In the experimental group, birth weight of the babies was higher, preterm birth was less common, and NICU admissions were reduced. Abstinence rates did decrease at 24 weeks postpartum (12 weeks after the incentives were discontinued), down to 15% in the experimental condition and 2% in the control condition, which was still a statistically significant difference.

Overall, the results so far are very promising. It would be interesting to know the cause of relapse back to smoking as time passes. Parenting an infant can be stressful and smoking can help alleviate stress. However, a reversal back to smoking could also be due to the loss of financial incentives. Another factor is intrinsic vs extrinsic motivation. That is, did they quit because they were motivated more by an internal desire to quit smoking or by the external rewards: health of their baby and financial incentives? The answer will likely include both types. The results of this study are informative for how to help women successfully quit smoking during pregnancy and protect their fetuses from the harmful effects of in utero smoke exposure, and important for groups designing incentive smoking cessation programs.