Switching to electronic cigarettes (e-cigarettes) may be a useful strategy for reducing harm caused by combustible cigarettes in Black and Latinx smokers, according to a study.
Cigarette smokers may switch to e-cigarettes in an attempt to kick the habit, although it is not yet clear whether this strategy is actually associated with less harm, notably whether exposure to nicotine is reduced. Here, researchers compared the harm incurred from the use of nicotine salt pod system (NSPS) e-cigarettes—the most common type on the market currently—versus combustible cigarettes in Black and Latinx smokers.
The researchers found that switching to e-cigarettes did not increase nicotine exposure, and they further observed that it was associated with short-term urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) concentration reduction.
They randomized Black and Latinx participants in San Diego, Calif., and Kansas City, Mo., who smoked at least five combustible cigarettes a day on at least 25 of the past 30 days for at least six months to either e-cigarettes or combustible cigarettes (control group) for six weeks. The e-cigarette group had a choice of pod flavors, which were 5% nicotine, and underwent education, training, and action planning to make the transition from combustible cigarettes to e-cigarettes; the control group continued smoking as usual. The main outcome measure was NNAL concentration at the end of the intervention. Other outcomes included change in urinary cotinine, expired carbon monoxide (CO), respiratory symptoms, lung function, blood pressure, and seven-day history of combustible cigarette consumption. The e-cigarette group was also evaluated for two- and six-week switching rates. and switching rates (e-cigarette group only) at weeks 2 and 6. The study took place between 2018 and 2019, with data analyzation performed between Sept. 18, 2019, and Sept. 4, 2020.
Final analysis included 186 Black (n=92) and Latinx (n=94) participants, with a mean (standard deviation [SD]) age of 43.3 (12.5) years; 40.3% of the cohort was female. At baseline, the mean (SD) number of cigarettes smoked per day was 12.1 (7.2) on 6.8 (0.6) days per week. The e-cigarette group had 125 participants, and the control group had 61 participants.
The median (interquartile range) NNAL was 124 (45–197) pg/mL in the e-cigarette group and 88 (58–197) pg/mL in the control group at baseline. After six weeks, the e-cigarette group, compared to the control group, had much greater reductions in NNAL (relative risk [RR], 0.36; 95% confidence interval [CI], 0.23–0.54; P<0.001), CO (RR, 0.53; 95% CI, 0.42–0.68; P<0.001), respiratory symptoms (RR, 0.63; 95% CI, 0.47–0.85; P=0.002), and seven-day history of cigarettes smoked among participants still smoking (RR, 0.30; 95% CI, 0.20–0.43; P<0.001). The e-cigarette group also maintained cotinine levels (RR, 0.80; 95% CI, 0.58–1.10; P=0.17). No significant changes or between-group differences were observed in lung function and diastolic and systolic blood pressure. At week six in the e-cigarette group, 28.1% of participants were only using e-cigarettes, 57.9% were using e-cigarettes and combustible cigarettes, and 14% of participants had resumed using only combustible cigarettes.
The study was published in JAMA Network Open.
“Reduction in cigarettes and biomarkers of exposure in this study suggest potential of NSPS e-cigarettes as a harm reduction strategy for members of the 2 largest minority groups in the US who face significant health disparities,” the researchers concluded.