The time course of compensatory puffing with an electronic cigarette: Secondary analysis of real-world puffing data with high and low nicotine concentration under fixed and adjustable power settings

Abstract Introduction In a secondary analysis of our published data demonstrating compensatory vaping behaviour (increased puff number, puff duration and device power) with e-cigarettes refilled with low vs. high nicotine concentration e-liquid, here we examine 5-day time course over which compensatory behaviour occurs under fixed and adjustable power settings. Methods Nineteen experienced vapers (37.90±10.66 years, 8 females) vaped ad libitum for 5 consecutive days under four counterbalanced conditions (i.e. 20 days in total): i) low nicotine (6mg/mL)/fixed power (4.0V/10W); ii) low nicotine/adjustable power; iii) high nicotine (18mg/mL)/fixed power; iv) high nicotine/adjustable power (at 1.6 Ohm). Puff number, puff duration and power settings were recorded by the device. For each day, total daily puffing time was calculated by multiplying daily puff number by mean daily puff duration. Results A significant day x setting interaction revealed that whilst puffing compensation (daily puffing time) continued to increase over 5 days under fixed power, it remained stable when power settings were adjustable. Separate analysis for puff number and puff duration suggested that the puffing compensatory behaviour was largely maintained via longer puff duration. Conclusion Under fixed power conditions (4.0V/10W), vapers appear to compensate for poor nicotine delivery by taking longer puffs and this compensatory puffing appears to be maintained over time.