Trends in utilization of smoking cessation agents before and after the passage of FDA boxed warning in the United States.
BACKGROUND
In 2009, the FDA required a black box warning (BBW) on bupropion and varenicline, the two commonly prescribed smoking cessation agents due to reports of adverse neuropsychiatric events. We investigated if there was a decline in use of bupropion and varenicline after the BBW by comparing the percent using these medications before and after BBW.


METHODS
We conducted a retrospective observational study using data from the Medical Expenditure Panel Survey from 2007 to 2014. The study sample consisted of adult smokers, who were advised by their physicians to quit smoking. We divided the time period into "pre-warning", "post-warning: immediate", and "post-warning: late." Unadjusted analysis using chi-square tests and adjusted analyses using logistic regressions were conducted to evaluate the change in bupropion and varenicline use before and after the BBW. Secondary analyses using piecewise regression were also conducted.


RESULTS
On an average, 49.04% of smokers were advised by their physicians to quit smoking. We observed a statistically significant decline in varenicline use from 22.1% in year 2007 to 9.23% in 2014 (p value<0.001). In the logistic (Adjusted Odds Ratio=0.36, 95% CI=0.22-0.58) and piecewise regressions (Odds Ratio=0.64, 95% CI=0.41-0.99) smokers who were advised to quit smoking by their physicians were less likely to use varenicline in the immediate post-BBW period as compared to pre-BBW period. While the use of varenicline continued to be significantly low in the late post-BBW period (AOR=0.45, 95% CI=0.31-0.64) as compared to the pre-BBW period, the trend in use as seen in piecewise regression remained stable (OR=0.90, 95% CI=0.75-1.06). We did not observe significant differences in bupropion use between the pre- and post-BBW periods.


CONCLUSION
The passage of the FDA boxed warning was associated with a significant decline in the use of varenicline, but not in the use of bupropion.
['Shah|Drishti|D|', 'Shah|Anuj|A|', 'Tan|Xi|X|', 'Sambamoorthi|Usha|U|']
D000293:Adolescent D000328:Adult D000368:Aged D016642:Bupropion D003430:Cross-Sectional Studies D004348:Drug Labeling D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D018722:Nicotinic Agonists D012189:Retrospective Studies D012907:Smoking D016540:Smoking Cessation D061485:Tobacco Use Cessation Devices D014481:United States D014486:United States Food and Drug Administration D000068580:Varenicline D055815:Young Adult
Trends Smoking cessation agents Boxed warning Bupropion Varenicline Neuropsychiatric adverse events