Variability in Puff Topography and Exhaled CO in Waterpipe Tobacco Smoking

We examined intra-individual variability in puff topography and CO measures collected during laboratory waterpipe (WP) tobacco smoking using a research-grade waterpipe (RWP).

WP smoking topography and exhaled CO measures were obtained from 10 established WP smokers in a single-blind, crossover design. Using a previously validated RWP, each participant smoked "Two Apples" WP tobacco ad libitum with a single quick-light charcoal to satiation in 3 laboratory sessions spaced at least one week apart. To examine the intra-individual variability, the intraclass correlation coefficient (ρ) for topography and CO measures were estimated. Results: The majority of the topography and CO measures were stable. Most stable were puff frequency (ρ = 0.88), number of puffs (ρ = 0.86), and puff duration (ρ = 0.80). Less stable were peak flow (ρ = 0.57) and total puff volume (ρ = 0.52).

The results provide the first set of empirical evidence that most topography and CO measurements collected using the RWP from a single laboratory smoking session are stable such that they can be representative of a smoker's puffing behaviors and reproducible among 3 sessions spread equally across 3 weeks.