CO exposure and puff topography are associated with Lebanese waterpipe dependence scale score.

Background: Waterpipe tobacco smoking involves self-administration of the dependence-producing drug nicotine. Few studies have examined if dependence in waterpipe smokers influences toxicant exposure and smoking behavior.

Methods: Current waterpipe tobacco smokers were categorized based on Lebanese Waterpipe Dependence Scale-11 (LWDS-11) score (LWDS-11: LOW < 7; N = 59; HIGH > 13; N = 59). Participants abstained from smoking for 12 hr and then completed a single 30-min waterpipe tobacco smoking episode. Expired-air carbon monoxide (CO) was measured before and 5 min after smoking and puff topography was measured during smoking.

Results: Total mean smoking time was 30.9 min (SD = 3.5) and did not differ significantly by LWDS-11 score. CO boost was greater for participants in the HIGH versus LOW groups (62.3 vs. 43.6 ppm, p < .01). Similarly, those in the HIGH versus LOW group took more puffs (198.6 vs. 157.1 puffs, p < .01), longer duration puffs (2.7 vs. 2.3 s, p < .05), puffs with lower flow rate (10.3 vs. 12.6 L/min, p < .01), and less time between puffs (8.0 vs. 12.4 s, p < .001).

Conclusions: The puff topography of waterpipe tobacco smokers can be predicted by LWDS-11 score, with those scoring higher taking longer duration and lower velocity puffs at a higher frequency. These behavioral differences may underlie the 40% greater CO exposure observed for those with higher LWDS-11 scores. To the extent that waterpipe dependence is associated with more smoke inhalation, more dependent smokers will be exposed to greater amounts of toxic smoke constituents.