The interaction of sociological and biological factors in adolescent cigarette smoking

Individual variations in motives for nicotine self-administration in male rats: evidence in support for a precision psychopharmacology

The significant heterogeneity in smoking behavior among smokers, coupled with the inconsistent efficacy of approved smoking cessation therapies, supports the presence of individual variations in the mechanisms underlying smoking. This emphasizes the need to shift from standardized to personalized smoking cessation therapies. However, informed precision medicine demands precision fundamental research. Tobacco smoking is influenced and sustained by diverse psychopharmacological interactions between nicotine and environmental stimuli. In the classical experimental rodent model for studying tobacco dependence, namely intravenous self-administration of nicotine, seeking behavior is reinforced by the combined delivery of nicotine and a discrete cue (nicotine+cue). Whether self-administration behavior is driven by the same psychopharmacological mechanisms across individual rats remains unknown and unexplored. To address this, we employed behavioral pharmacology and unbiased cluster analysis to investigate individual differences in the mechanisms supporting classical intravenous nicotine self-administration (0.04 mg/kg/infusion) in male outbred Sprague-Dawley rats. Our analysis identified two clusters: one subset of rats sought nicotine primarily for its reinforcing effects, while the second subset sought nicotine to enhance the reinforcing effects of the discrete cue. Varenicline (1 mg/kg i.p.) reduced seeking behavior in the former group, whereas it tended to increase in the latter group. Crucially, despite this fundamental qualitative difference revealed by behavioral manipulation, the two clusters exhibited quantitatively identical nicotine+cue self-administration behavior. The traditional application of rodent models to study the reinforcing and addictive effects of nicotine may mask individual variability in the underlying motivational mechanisms. Accounting for this variability could significantly enhance the predictive validity of translational research.

How Adverse Childhood Experiences and Gender Shape Perceptions of Synthetic Drug Use and Desistance in Yunnan, China

Past research on illicit drug use and desistance has primarily been conducted in western countries, relied on quantitative data, and given little attention to potential gender differentiation. Utilizing qualitative data, we explore gender differences in how illicit drug users perceive the onset of use, whether or not they connect this to adverse childhood experiences (ACEs), and why they quit. The work is based on a sample of 24 informants from Yunnan. Women link onset of use to adverse childhood experiences (ACE) and report quitting primarily for their children. Men found support from their families helpful in ending illicit drug use. This adds qualitative support to theoretical work done by Wu and colleagues, Zhang, and Zhang and Demant who argue that familial attachment is critical in desistance. Utilizing a gendered lens, we gain and nuanced understanding of illicit drug use and links to ACEs which may better inform intervention programs.

Salivary testosterone as a potential indicator for risky behaviour associated with smoking-related peer pressure in adolescents

Early smoking is considered an indicator for risky behaviour in adolescents. Although social indicators predicting adolescent smoking are known, biological indicators have not been defined. This study aimed to establish whether salivary testosterone could be used as a "predictive biomarker" for smoking-associated peer pressure. Saliva samples were collected from Bruneian adolescents (aged 13-17 years) by the passive drool method. Salivary testosterone concentration was determined by enzyme-linked immunosorbent assay. Salivary testosterone concentration and smoking-associated peer pressure indicators were compared between adolescent males and females and statistical significance was determined by an independent samples t-test. A significant positive relationship between smoking-associated peer pressure and salivary testosterone levels in adolescents was found. However, this relationship was not significant when males and females were considered separately. Our data suggest that students who have tried cigarette smoking and have friends who are cigarette smokers have higher salivary testosterone levels.

Biosocial processes predicting multisystemic therapy treatment response

This study examined biological (testosterone) and social (deviant peer affiliation) factors early in treatment as predictors of treatment outcome among adolescent boys receiving Multisystemic Therapy (MST) in community settings. Outcome variables included changes in youth aggression and delinquency as reported by the primary caregiver. Testosterone and deviant peer affiliation were assessed at treatment onset; and outcome variables (aggression and delinquency) were assessed at treatment onset, mid-treatment and end-of-treatment. Participants were 112 adolescent boys (M age=15.42, SD=1.31) and their caregivers. Growth curve analyses revealed that the combination of high testosterone and high deviant peer affiliation early in treatment were significantly associated with less of a decline in aggression and delinquency over the course of treatment. Results provide novel evidence for the role of testosterone in the prediction of future externalizing behaviors. Clinical and theoretical implications are discussed.

Does mother's smoking influence girls' smoking more than boys' smoking? A 20-year review of the literature using a sex- and gender-based analysis

A systematic literature review was conducted to examine whether mother's smoking influences girls' smoking more than boys' smoking. Fifty-seven studies, published between 1989 and 2009, were analyzed using a sex and gender lens. Results indicate that mother's prenatal and postnatal smoking influences girls' smoking more than boys' smoking. Despite evidence that sex and gender are important determinants of smoking among adolescents when examined in relation to mother's smoking, the theoretical understanding of why girls are more likely to smoke if prenatally and postnatally exposed to mother's smoking remains unclear. Implications for future research are discussed.

Sex and ovarian hormones influence vulnerability and motivation for nicotine during adolescence in rats

The purpose of this study was to examine sex differences in sensitivity to nicotine's reinforcing effects during adolescence, a hormone transition phase characterized by rapid and marked changes in levels of gonadal hormones. Male and female rats were trained to self-administer nicotine (5 or 10 microg/kg/infusion) under a fixed-ratio 1 schedule beginning on postnatal day 30. Following acquisition, responding was assessed under a progressive-ratio schedule until postnatal day 45 with blood sampling occurring prior to the first 5 sessions in order to determine the relationship between gonadal hormones (i.e., estradiol and progesterone in females and testosterone in males) and responding for nicotine. Under low dose conditions, a greater percentage of females than males acquired nicotine self-administration. Under progressive-ratio testing conditions, although adolescent females and males initially responded at similar levels, by the end of the adolescent testing period, females responded at higher levels than males to obtain nicotine infusions. Levels of responding under the progressive-ratio schedule were negatively associated with progesterone and positively associated with the ratio of estradiol to progesterone. These findings demonstrate an enhanced sensitivity in adolescent females as compared to adolescent males to nicotine's reinforcing effects with evidence implicating circulating hormone levels as modulating this sensitivity.

A Test of Biosocial Models of Adolescent Cigarette and Alcohol Involvement

We tested biosocial models that posit interactions between biological variables (testosterone, estradiol, pubertal status, and pubertal timing) and social context variables (family, peer, school, and neighborhood) in predicting adolescent involvement with cigarettes and alcohol in a sample of 409 adolescents in grades 6 and 8. Models including the biological and contextual variables and their interactions explained significantly more variance in adolescent cigarette and alcohol involvement than did models including only the main effects of the biological and contextual variables. Post-hoc analyses of significant interactions suggested that, in most case, moderation occurred in the hypothesized direction. Consistent with dual hazards models of adolescent antisocial behaviors, the relationships between the biological and substance use variables became positive and stronger as the context became more harmful. Considerations of adolescent substance use, and perhaps other problem behaviors, should recognize the possible role of biological variables and how their influence may vary by social context.

Psychobiological correlates of smoking in patients with erectile dysfunction

Although it is clear that cigarette abuse is closely linked to sexual dysfunction, it is still unclear which are the psychobiological correlates of smoking among individuals with sexual dysfunction. The aim of the present study is the assessment of the organic, psychogenic and relational correlates of erectile dysfunction (ED) in outpatients with different smoking habits. We studied the psychobiological correlates of smoking behaviour in a consecutive series of 1150 male patients, seeking medical care for ED. All patients were investigated using a Structured Interview (SIEDY), which explores the organic, relational and intra-psychic components of ED, and a self-administered questionnaire for general psychopathology (MHQ). In addition, several biochemical and instrumental parameters were studied, to clarify the biological components underlying ED. Current smokers (CS) showed a higher activation of the hypothalamus-pituitary-testis axis (higher LH, testosterone and right testicular volume) and lower levels of both prolactin and TSH. Hormonal changes were reverted after smoking cessation. CS showed a higher degree of somatized anxiety and were more often unsatisfied of their occupational and domestic lifestyle. Smoking, as part of a risky behaviour, was significantly associated with abuse of alcohol and cannabis. Both CS and past smokers (PS) showed an impairment of subjective and objective (dynamic peak systolic velocity at penile duplex ultrasound) erectile parameters. This might be due to a direct atherogenic effect of smoking, a cigarette-induced alteration of lipid profile (higher triglyceride and lower HDL cholesterol in CS than in non-smokers or PS), or due to a higher use of medications potentially interfering with sexual function. This is the first comprehensive evaluation of the biological and intrapsychic correlates to the smoking habit. Our report demonstrates that smoking has a strong negative impact on male sexual life, even if it is associated at an apparently more sexual-favourable hormonal milieu.

Familial influences on adolescent smoking

The family unit is the primary source of transmission of basic social, cultural, genetic, and biological factors that may underlie individual differences in smoking. Existing information on the role of familial factors in tobacco use is characterized by two separate, but somewhat overlapping, lines of research: genetic epidemiological studies and risk-factor research. The present paper summarizes and evaluates studies assessing the association between adolescent smoking and parent and sibling smoking behaviors. A review of 87 studies reveals that methods are limited by a lack of standardized instruments, failure to measure important confounding and mediating factors, reliance on cross-sectional designs and the use of inconsistent definitions of tobacco-related behavior and assessment procedures. Moreover, there are no systematic family studies of the acquisition and continuation of smoking that have employed contemporary methodological standards for examining familial aggregation of tobacco behaviors among adolescents. Findings across studies show weak and inconsistent associations between parent and adolescent smoking; inconsistent findings may be attributed to methodological issues or associated factors that may complicate the relation between parent and adolescent smoking. Sibling and peer smoking show greater associations with adolescent smoking. Suggestions for future research include contemporary family studies that delineate meaningful phenotypes of tobacco use and prospective work on the later stages of tobacco use and the timing of the influence and valence of parent and family factors. Integration of the risk factor approach within the family study design may enrich both approaches to elucidate familial influences on smoking.

Smoking and high-risk sexual behavior among young adults in Hong Kong

Young adults (n = 964; never married; age, 18-27 years) in Hong Kong were surveyed to obtain information about their smoking habits and sexual behaviors. Current smokers (15% of the entire sample) and those who had ever had sexual intercourse (28%) were more likely to be male, to have ended their education at secondary school, and to report less life satisfaction. After controlling for demographic and psychosocial correlates, sexual intercourse was associated with smoking status for both males and females. Among those who were sexually active, those who had multiple sexual partners, had their first sexual experience prior to age 18 years, and (for males) reported visiting massage parlors were more likely to have a history of smoking. Our findings extend those of our previous study with community adolescents in Hong Kong and suggest that smoking may be a marker for other high-risk behaviors among young Chinese adults.

The association of testosterone with nicotine use in young adult females

This pilot laboratory study examined the relationship of testosterone levels, carbon monoxide (CO) levels, current and adolescent nicotine use, and histories of pubertal onset in 30 young adult female smokers. These females had completed questionnaires regarding nicotine use in the 7th through 10th grades, and again at age 21 as part of a cohort study of drug use. In addition, history of pubertal onset was obtained at age 21, as were testosterone and CO levels. Testosterone levels were positively correlated with cigarette use in the last 30 days (P< or =.01), CO levels (P< or =.05), cigarette use reported in the 7th and 10th grades (P< or =.05), and negatively correlated with age of pubertal onset (P< or =.001). The relationship of testosterone to nicotine will be discussed.

Initial tobacco use episodes in children and adolescents: current knowledge, future directions

Approximately three-quarters of adult tobacco users report that their first tobacco use occurred between ages 11 and 17, while many adults who do not regularly use tobacco report that they experimented with it as adolescents. Surprisingly little is known about the effects of these initial tobacco use episodes and their influence on adult tobacco use patterns. In particular, understanding the role that nicotine plays in these early tobacco use experiences may be important in understanding the development of regular tobacco use and concomitant nicotine dependence. One goal of this review is to summarize current knowledge regarding the effects of initial tobacco use episodes in adolescents and to discuss nicotine exposure in initial tobacco use episodes. Another goal is to outline a research agenda designed to learn more about initial tobacco use episodes and the effects of nicotine in children. An ethical rationale and some potential methods for this research agenda are presented.

Prenatal effects of maternal smoking on daughters' smoking: nicotine or testosterone exposure?

OBJECTIVES

The purpose of this study was to specify the effect of prenatal fetal exposure to maternal cotinine and testosterone on daughters' smoking in adolescence and adulthood.

METHODS

Longitudinal causal models were estimated among 240 White mother-daughter pairs from the Child Health and Development Study. Mothers and daughters were reinterviewed when daughters were aged 15 to 17 years, and daughters were interviewed at 27 to 30 years of age. Blood samples were obtained from both parents during pregnancy and from adult daughters.

RESULTS

Testosterone and smoking were positively correlated among mothers during their pregnancy and among adult daughters. Maternal prenatal cotinine had no direct effect on daughters' smoking; self-reported smoking in pregnancy did have a direct effect. Smoking among daughters during adolescence was determined by maternal prenatal testosterone and self-reported maternal smoking during pregnancy and postnatally. Smoking among adult daughters reflected chronic smoking since adolescence and the continuing effect of postnatal maternal smoking. Prenatal maternal testosterone affected adult daughters' testosterone.

CONCLUSIONS

Estimates of the impact of prenatal maternal smoking depend on the measure of smoking. Prenatal testosterone exposure is a previously unrecognized risk factor for smoking among female offspring.

Psychosocial factors related to adolescent smoking: a critical review of the literature

OBJECTIVE

To extend the analysis of psychosocial risk factors for smoking presented in the United States surgeon general's 1994 report on smoking and health, and to propose a theoretical frame of reference for understanding the development of smoking.

DATA SOURCES

General Science Index, Medline, PsycLIT, Sociofile, Sociological Abstracts, and Smoking and Health. Holdings of the Addiction Research Foundation of Ontario Library as well as the authors' personal files.

STUDY SELECTION

Reviewed literature focused on studies that examined the association of sociodemographic, environmental, behavioural, and personal variables with smoking.

DATA SYNTHESIS

Adolescent smoking was associated with age, ethnicity, family structure, parental socioeconomic status, personal income, parental smoking, parental attitudes, sibling smoking, peer smoking, peer attitudes and norms, family environment, attachment to family and friends, school factors, risk behaviours, lifestyle, stress, depression/distress, self-esteem, attitudes, and health concerns. It is unclear whether adolescent smoking is related to other psychosocial variables.

CONCLUSIONS

Attempts should be made to use common definitions of outcome and predictor variables. Analyses should include multivariate and bivariate models, with some attempt in the multivariate models to test specific hypotheses. Future research should be theory driven and consider the range of possible factors, such as social, personal, economic, environmental, biological, and physiological influences, that may influence smoking behaviour. The apparent inconsistencies in relationships between parental socioeconomic status and adolescent disposable income need to be resolved as does the underlying constructs for which socioeconomic status is a proxy.