Psychiatry Research EG

Tobacco is currently used by 1.3 billion individuals, of whom 80% live in developing and transitional economy countries. Tobacco is currently the second major cause of death worldwide, being responsible for the deaths of one in 10 adults worldwide, five million deaths each year. It is the fourth most common risk factor for disease worldwide. If the current smoking patterns continue, 10 million tobacco-related deaths per year will occur by 2020. Of the roughly 650 million individuals who are smoking today, about half will eventually die due smoking complications [1]. The economic costs of tobacco use include the high public health costs of treating tobacco-caused diseases, depriving families of breadwinners and nations of a healthy workforce as tobacco kills individuals at the height of their productivity and lowers productivity while tobacco users are alive, because of increased sickness [2]. The intensity, duration, and pattern of nicotine abstinence effects can vary widely across individuals [3]. Indeed, studies have identified several predictors of the severity and quality of abstinence effects [4], including psychiatric conditions [5], alcohol problems [6], and sex [7]. It is important to identity the predictors of abstinence effects because interventions can be selected on the basis of a patient’s characteristics. For example, Pomerleaue et al. [5] reported that depressed smokers are at an increased risk of experiencing depressed mood during nicotine abstinence and may therefore require mood management interventions to buffer these effects before a quit attempt [8]. Personality is also a significant clinical characteristic that influences smoking patterns and may impact expressions of nicotine withdrawal [9]. Several different theories and measures of personality have been used in the smoking literature, including Eysenck’s personality scales [10], Zuckerman’s sensation seeking scale [11], Barratt’s impulsivity scale [12], and Costa and McCrae’s NEO – five-factor inventory) [9]. These measures are designed to identify psychometrically supported affective and behavioral patterns in humans. In contrast, Cloninger’s psychobiological model of personality [13] is unique because it is based on a synthesis of information from twin and family studies, investigations of longitudinal development, neuropharmacological and neurobehavioral studies of learning in humans and other animals, and psychometric analyses of personality in individual and twin pairs [14]. This model identifies personality dimensions that may be manifestations of genetically transmitted neuropharmacological processes [15–17]. These personality dimensions can be assessed by the temperament and character inventory (TCI) [18]. The factorial structures of temperament dimensions of the TCI have been supported in several studies [13,19]. The heritability of the TCI’s temperament dimensions has been supported by a large twin study that reported heritability rates between 50 and 65% [20]. Nevertheless, there remains some debate about the pharmacogenetic and psychometric specificity of these dimensions [21]. Cloninger’s theory is especially relevant to smoking for several reasons. First, the behaviors assessed in TCI dimensions (e.g. impulsivity, intolerance of uncertainty) are conceptually relevant to the initiation and maintenance of nicotine dependence. For example, impulsive individuals high in novelty seeking (NS) may become more frustrated when restricted from nicotine reward and therefore may experience greater negative affect during tobacco abstinence. Second, the TCI measures heritable traits that may mediate relations between genotypes and smoking behavior [22]. For example, Elovainio et al. [22] reported that the effect of the dopamine D4 receptor genotype on smoking behavior was mediated by NS. Third, systems involved in processing and responding to appetitive, aversive, and novel stimuli that are related to TCI temperament dimensions may also underlie smoking behavior [23]. Specifically, responding to aversive stimuli, such as the physical sensations of nicotine withdrawal, may be exaggerated in individuals with particular TCI profiles. Fourth, the pharmacological correlates of TCI dimensions may be related to the pathophysiology of nicotine addiction [24]. Indeed, dopaminergic and serotonergic systems, which are related to NS and harm avoidance (HA), have been implicated in nicotine withdrawal [24]. There has been a considerable degree of research on the association between TCI dimensions and smoking. Many studies have reported that NS is associated with various components of smoking behavior, including tobacco-use initiation, smoking status, and the severity of nicotine dependence [20,22,25–30]. HA and reward dependence (RD) have been reported to be modestly associated with smoking initiation and the severity of nicotine dependence in some studies [20,25,30–32]. However, in other studies, RD has been reported to be associated negatively with tobacco dependence [30]. Given that there is a link between temperament scores on the TCI and various smoking characteristics, it is possible that smokers with different temperaments may show different patterns of acute tobacco withdrawal. From the well-known relationship between smoking and personality, the main objective of this study was to test the association of personality profile and motivation to quit smoking. In addition, this study aimed to compare between those who were motivated to quit but could not maintain the abstinence (relapsed motivated group) and those who were able to maintain the abstinence (nonrelapsed motivated group).