To Get Pregnant Smokers to Quit, Money Talks

Cold cash proved to be an effective incentive for pregnant French women to stop smoking during gestation, a randomized trial indicated.

Quit rates were doubled in a group rewarded with money for confirmed abstinence, relative to a control group that received payments for showing up to clinic visits but not for actual smoking cessation (16% vs 7%; OR 2.45, 95% CI 1.34-4.49), reported Ivan Berlin, MD, PhD, of Hôpital Pitié-Salpêtrière-Sorbonne Université in Paris, and colleagues.

The paid-for-abstinence group could receive as much as €520 (~$600); the maximum payment for control participants was €120 (~$140), the group explained in The BMJ.

Other factors related to the strength of participants’ smoking habits were also diminished in the group paid to maintain abstinence. These included time to smoking resumption and participants’ ratings of their tobacco craving.

Perhaps more importantly, the financial incentives appeared to benefit participants’ babies, with lower risk of poor neonatal outcomes (2% in the intervention group vs 9% among controls, P=0.003).

An accompanying BMJ editorial by three Dutch and British researchers applauded the study, saying it “adds to growing evidence that the time is right to start including incentives as part of standard practice to support smoking cessation during pregnancy.”

How it might work in the U.S. is another question. Besides parents and infants, the principal beneficiaries of improved maternal and neonatal health are their healthcare payers, i.e., private and public insurers. In theory they could reduce or waive premiums for pregnant smokers. Whether that would serve as well as direct cash payments, which would represent an entirely new model for insurers, is unclear.

Dubbed FISCP, the trial randomized 460 pregnant smokers 1:1 to each of the two arms. Participants reported smoking at least five regular cigarettes per day (or three that they rolled themselves) and were at less than 18 weeks’ gestation. All received €20 vouchers at each monthly clinic visit, with six scheduled. The intervention group received additional vouchers both for demonstrating abstinence at each visit (via self-report and expired carbon monoxide testing) and also for maintaining it over time. These additional vouchers added up to as much as €400 (~$460) for participants who were confirmed abstinent throughout the trial.

At any given clinic visit, abstinence at that point ranged from 25% to 40% over the five follow-up visits with the financial incentives, compared with about 12% to 21% among controls. The median point at which abstinence was lost was visit 5 in the intervention group, versus visit 4 for controls.

A total of 451 live births were recorded in the trial. Four in the intervention group and 18 in the control group had poor neonatal outcomes, defined as a composite of transfer to neonatal intensive care, congenital defect, convulsions, or perinatal death.

In addition, a post-hoc analysis (i.e., not included in the original protocol) found that fewer babies in the intervention group had low birth weight, with an odds ratio for weight ≥2,500 g of 1.95 (95% CI 0.99-3.85). On the other hand, mean birth weight was only 50 g lower in the control group, which did not approach statistical significance. Berlin and colleagues explained the discrepancy by suggesting “the effect of the financial incentives on birth weight might not be linear.”

The editorialists, headed by Leonieke J. Breunis, MD, of University Medical Centre Rotterdam in the Netherlands, did not appear bothered by the low rate of full abstinence or the questionable difference in infant birth weight. They did, however, see a need for additional research to answer outstanding questions, such as, “what is the optimal incentive scheme (i.e., timing, frequency, value, duration, and type of incentive)? Who should deliver that scheme, and how? Could personalized incentives be more effective than a one-size-fits-all approach? Would involvement of a significant other (such as a partner) in the intervention increase effectiveness?”

But provision of financial incentives should not wait for answers to those questions, the group suggested. Rather, “we argue that implementation should be pursued in parallel with ongoing and future research,” Breunis and colleagues wrote.