A review of the literature on the degree of "compensatory" smoking of low-delivery cigarettes
To review trends in measures of compensatory smoking behavior over time and by method of assessment.Introduction. An analysis of the papers published on "compensatory" smoking, observed when smokers switch to lower-yielding products from higher-yielding products (yields determined on smoking machines), indicates that compensation clearly does occur. However, differences in the degree of compensation reported, according to the approach taken for the measurement of compensation, have not previously been reviewed.Results. Almost all studies using the "voluntary switching" concept (smokers selecting longterm their own brands, with no experimental switching) show tobacco-specific biomarker (e.g. serum or urine cotinine) responses that are intermediate between those that would be expected for complete compensation (compensation index, CI, =1), and for absorption of the ISO yields of nicotine (CI=O). The "voluntary switching" data show that daily exposure in smokers of lower-yielding cigarettes may be somewhat higher than would be expected, based on nominal yields, but that the exposures are much lower than would be expected, if compensation were complete. These conclusions are further compared to a number of studies that have looked at different aspects of compensation such as puffing behavior, vent blocking and numbers of cigarettes smoked per day.Implications. An overall judgment is for a CI of ~0.6, considerably less than complete compensation. Smokers of lower-yielding cigarettes do indeed have lower daily exposures of nicotine.