Validity of a demand curve measure of nicotine reinforcement with adolescent smokers

Abstract

High or inelastic demand for drugs is central to many laboratory and theoretical models of drug abuse, but it has not been widely measured with human substance abusers. The authors used a simulated cigarette purchase task to generate a demand curve measure of nicotine reinforcement in a sample of 138 adolescent smokers. Participants reported the number of cigarettes they would purchase and smoke in a hypothetical day across a range of prices, and their responses were welldescribed by a regression equation that has been used to construct demand curves in drug selfadministration studies. Several demand curve measures were generated, including breakpoint, intensity, elasticity, P max , and O max . Although simulated cigarette smoking was price sensitive, smoking levels were high (8+ cigarettes/day) at prices up to 50¢ per cigarette, and the majority of the sample reported that they would purchase at least 1 cigarette at prices as high as $2.50 per cigarette. Higher scores on the demand indices O max (maximum cigarette purchase expenditure), intensity (reported smoking level when cigarettes were free), and breakpoint (the first price to completely suppress consumption), and lower elasticity (sensitivity of cigarette consumption to increases in cost), were associated with greater levels of naturalistic smoking and nicotine dependence. Greater demand intensity was associated with lower motivation to change smoking. These results provide initial support for the validity of a self-report cigarette purchase task as a measure of economic demand for nicotine with adolescent smokers.

Economic demand predicts addiction-like behavior and therapeutic efficacy of oxytocin in the rat

“…Thus, in this case both punishment resistance and preferred level of drug intake are expected to contribute to the total shock selfadministered. Of note, Q 0 has been reported to be associated with alcohol-related problems and misuse (10,11,14) and nicotine dependence (12,13), and could be a clinically relevant measure of addiction severity. This is consistent with the view that Q 0 parameter is similar to hedonic set point (8), a concept thought to be important in addiction behavior (31,43).…”

“…Economic demand is associated with measures of addiction in humans for several drugs, such as lifetime years of cocaine, heroin, marijuana, and benzodiazepine use (15); severity of alcohol dependence (10,11,14) and craving (16); as well as severity of nicotine dependence (12,13) and craving (17). A model of economic demand was recently validated in cocaine-dependent participants (9), providing the means for ready, direct comparison of animal and human studies of addiction treatments.…”

“…They offer a structured quantitative method to model behavior that is mathematically identical across species (7)(8)(9), and accruing evidence indicates economic-based descriptors of human behavior may be particularly useful biomarkers of addiction severity (10)(11)(12)(13)(14). Notably, economic demand has been shown to correlate with lifetime years of cocaine, heroin, marijuana, and benzodiazepine use (15); severity of alcohol dependence (10,11,14) and craving (16); as well as severity of nicotine dependence (12,13) and craving (17). However, economic demand has not yet been established as a biomarker of addictionlike behavior in animals, an essential final step in linking animal and human studies of addiction through economic demand.…”

Effects of Experimental Income on Demand for Potentially Real Cigarettes

“…Research has shown that demand indices obtained from hypothetical purchase tasks have a high correspondence to other measures of abuse or dependence severity [5][6][7][8] , and other behavioral economic valuation procedures demonstrate high concordance between hypothetical and real rewards.…”

“…These indices can be grouped into two main measures of consumption, demand intensity and demand elasticity, which are associated with use level and dependence severity. [5][6][7][8] Demand intensity is the amount of the commodity consumed when available at a very low cost approaching free, and demand elasticity quantifies the degree to which the individual is willing to increase monetary or effort-based expenditures to maintain the same level of consumption as costs increase. Elasticity of demand has been shown to be a characteristic of the drug itself and independent of drug dose.…”