However, Russell (1971) also posited that some smokers might be ��peak seekers,�� who are motivated by the immediate acute effects of nicotine and thus would not have to smoke constantly. mostly Perhaps peak seeking better explains ITS smoking, though it is not known what pharmacological effects ITS seek or achieve when they smoke. Another factor that may help maintain ITS smoking in the absence of traditionally construed dependence based on trough maintenance is stimulus control of smoking. In analyses of chippers��very low-level smokers��we found that their smoking was under considerable stimulus control, tending to occur only in some settings but not others (Shiffman & Paty, 2006). The same might be true of ITS.

If so, these tight stimulus associations, along with acute effects of nicotine, could maintain intermittent smoking and make it hard to quit, in the presence of the triggering stimuli. Such stimulus control may constitute an alternate path to persistent smoking, absent traditional withdrawal-based dependence. It might even be considered an alternative form of dependence. The fact that ITS show some signs of dependence and have difficulty quitting may need to be considered as nicotine policy is formulated. Whereas it is reasonable to assume that lowering nicotine delivery will undermine dependence that is based on nicotine regulation (Benowitz & Henningfield, 1994), it is less clear what effect it would have on the factors that maintain ITS smoking and make quitting difficult for ITS.

In particular, our data do not speak to the role of nicotine in ITS smoking, much less what effects of nicotine may reinforce and maintain ITS smoking and what dose-response function may govern these effects. From a public health point of view, ITS behavior should be of some concern because ITS do suffer ill effects from smoking (Luoto, Uutela, & Puska, 2000); however, their exposure to toxins and their subsequent risk is much less than that of DS, so promoting a shift from daily to nondaily smoking would be a public health benefit. The data also shed light on different approaches to assessing dependence. All the methods tested for assessing dependence significantly discriminated DS and ITS, and almost all also discriminated NITS and CITS. However, the dichotomous classification based on the HONC was considerably less discriminating, as it regarded all DS as dependent, and also evaluated almost all ITS��both NITS and CITS��as dependent. Dacomitinib This is perhaps not surprising, as the HONC seems to emphasize sensitivity over specificity, regarding any single sign of dependence as sufficient to classify a smoker as dependent. In contrast, the other dependence measures consider dependence to vary continuously in severity, making finer discriminations.