Almost half (40%) of recently hospitalized smokers enrolled in smoking cessation trials fail biochemical verification of self-reported abstinence from smoking, according to a recent study published in the journal Addiction.
“Participants may feel pressure to say they have quit when they have not, so it is essential in studies to verify claims of quitting using an objective test such as cotinine to know true quit rates,” said lead author Taneisha Scheuermann, PhD, researcher, University of Kansas Cancer Center, Kansas City, KA.
In the body, nicotine is converted into cotinine by the liver. Measuring cotinine via saliva sampling is a highly accurate measure of whether someone has smoked in the past few days.
Dr. Sheuermann and fellow researchers conducted this study, therefore, to estimate the prevalence and possible predictors of failed biochemical verification of self-reported smoking abstinence in subjects enrolled in trials of hospital-initiated smoking cessation interventions. They compared characteristics in subjects who verified, and those who failed to verify, self-reported smoking cessation.
They included 1,178 recently hospitalized smokers reporting tobacco abstinence for 6 months after randomization, who provided a saliva sample for verification, and who were enrolled in multi-site randomized clinical trials performed between 2010 and 2014 in hospitals throughout the US.
Adequate saliva samples were returned by 822 subjects, who reported that they had quit smoking for the past 7 days. In all, 57.8% of subjects were verified as quitting when the 10 ng/mL cut-off was used (95% CI: 54.4, 61.2) and 60.6% were verified at the 15 ng/mL cut-off (95% CI: 57.2, 63.9).
Researchers found that the factors independently associated with verification at the 10 ng/mL cut-off included education beyond high school (OR: 1.51; 95% CI: 1.07, 2.11), continuous abstinence since hospitalization (OR: 2.82; 95% CI: 2.02, 3.94), mailed vs in-person sample (OR: 3.20; 95% CI: 1.96, 5.21), and race. African American subjects were less likely to verify abstinence compared with white subjects (OR: 0.64; 95% CI: 0.44, 0.93).
These findings were similar for verification at the 15 ng/mL cut-off, and verification rates did not differ by treatment group.
Misreporting may have been even higher, as 18.6% of subjects who said they had quit smoking did not reply, despite multiple attempts and an offer of $50 to $100 for providing a sample.
Yet Dr. Scheuermann noted that the most important tool in helping smokers quit is not a biological test, but rather, the patient-provider relationship. Providers must recognize how difficult overcoming an addiction can be.
“Providers can create a non-judgmental, collaborative atmosphere that will help smokers better engage in the treatment process and discuss when they slip and smoke. They should tell patients that they know it’s hard to quit, and that they’re prepared to help patients change medications and sources of support until they get the right combination—the one that helps the patient quit,” she said.
Still, if patients do not accurately report their tobacco habits, providers cannot provide the best care.
“It’s hard to quit smoking. Slips and relapses are part of the normal process for quitting. We encourage smokers to be open with their health care providers about their struggles to quit. Providers can help them switch tactics to figure out the best strategy to help them quit for good,” Dr. Scheuermann concluded.