ABSTRACT
Introduction:
Smoking topography (ST) describes
smoking behavior and patterns. Removal of the
cigarette filter and subsequent impact on ST has not been investigated. This is the first
clinical trial comparing ST for filtered and unfiltered
cigarettes in a naturalistic experiment.
Methods:
We conducted a crossover
clinical trial following established people
who smoke cigarettes (n = 32) for two weeks under filtered and unfiltered
smoking experimental conditions. Participants (50 %
female, mean age 38.3 yr.) smoked in each experimental condition followed by a 3-week post-washout period. ST (puff count, volume, duration, peak and average flow) was measured at six
time-points.
Statistical analysis included a linear repeated mixed-effects model of
smoking experimental conditions by visit number and
sex.
Results:
Average flow (ml/sec) was significantly less for filtered
smoking (-6.92 lower (95 % CI -13.44 to -0.39), p < 0.05), thus demonstrating more resistance on
inhalation. No significant differences were found between filtered or unfiltered experimental conditions for other ST variables. However, average volume and average peak flow were somewhat higher in unfiltered
smoking, and lower mean puff counts/
cigarette were observed for unfiltered compared to filtered
smoking.
Conclusion:
Lower average flow rates were associated with filtered
cigarette smoking. No significant differences were found for other ST variables between
smoking experimental conditions. ST measurements comparing
cigarette smoking conditions may determine if product regulatory changes, such as removing the
cigarette filter could impact
smoking behavioral patterns among people
who smoke. This proof-of-principle study measuring ST may be replicated in larger trials to determine potential behavioral changes in
smoking unfiltered
cigarettes.