Behavioral economics of drug self-administration. III. A reanalysis of the nicotine regulation hypothesis.

The maintenance of a characteristic level of nicotine in a smoker's body is referred to as nicotine regulation. Considerable research has examined this question of whether smokers regulate nicotine intake. This is because nicotine regulation raises the question of whether smokers who, to decrease their intake of tar, switch to low tar/low nicotine cigarettes will increase the number and/or intensity of cigarettes smoked. Although the results of studies examining nicotine regulation are reported as generally consistent, considerable variability exists across these analyses such that the health hazards of smoking low tar/nicotine cigarettes remains uncertain. In the present analysis, these studies were analyzed to ascertain whether a behavioral-economic interpretation could better quantify the effects of changing nicotine yield on individuals' nicotine and smoke consumption. Specifically, 17 nicotine-regulation studies were reanalyzed using a unit-price analysis (i.e., cost-benefit analysis). The reanalysis showed less variability across regulation studies than previously reported; a positively-decelerating demand curve was found across most studies, consistent with previous unit-price analyses of food- and drug-maintained behavior. The benefits of this reanalysis versus the traditional regulation interpretation are that the behavioral economics approach: 1) brings unity to a variable set of data, 2) shows a nonlinear relationship, previously considered to be linear, between nicotine consumption and nicotine yield, 3) shows that nicotine yields higher, and not lower, than the smoker's usual brand decrease smoke consumption and thus decreases consumption of the harmful agents in tobacco, 4) better quantifies the data and provides a more parsimonious interpretation that generalizes to other drugs and food-maintained behavior in humans and nonhumans and, 5) integrates behavioral and pharmacological factors that control the consumption of reinforcers. These results suggest the value of behavioral economics in the study of consumptive behaviors and clinically suggest, in agreement with the studies contained herein, that decreasing the smoker's usual nicotine yield can have potential health risks for smokers who are unable to stop smoking.