Cigarette Smoking Trajectories in Adolescent Smokers: Does the Time Axis Metric Matter?

INTRODUCTION: Most studies modeling adolescent cigarette smoking trajectories use age as the time axis, possibly obscuring depiction of the natural course of cigarette smoking. We used a simulated example and real data to contrast smoking trajectories obtained from models that used time since smoking onset or calendar time (age) as the time axis. METHODS: Data were drawn from a longitudinal investigation of 1293 grade 7 students (mean age 12.8 years) recruited from 10 high schools in Montreal, Canada in 1999-2000, who were followed into young adulthood. Cigarette consumption was measured every 3 months during high school, and again at mean ages 20.4 and 24.0. Analyses using time since onset of smoking as the time metric was restricted to 307 incident smokers; analysis using calendar time included 645 prevalent and incident smokers. Smoking status and nicotine dependence (ND) were assessed at mean ages 20.4 and 24.0. Simulated data mimicked the real study during high school. RESULTS: Use of different time metrics resulted in different numbers and shapes of trajectories in the simulated and real datasets. Participants in the calendar time analyses reported more ND in young adulthood, reflecting inclusion of 388 prevalent smokers who had smoked for longer durations. CONCLUSIONS: Choosing the right time metric for trajectory analysis should be balanced against research intent. Trajectory analyses using the time since onset metric depict the natural course of smoking in incident smokers. Those using calendar time offer a snapshot of smoking across ages during a given time period. IMPLICATIONS: This study uses simulated and real data to show that trajectory analyses of cigarette smoking that use calendar time (e.g., age) versus time since onset as the time axis metric tell a different story. Trajectory analyses using the time since onset metric depict the natural course of smoking in incident smokers. Those using calendar time offer a snapshot of smoking across ages during a given time period. Choosing the right time metric should be balanced against research intent.

Secondhand Smoke Exposure and Depressive Symptoms in Children: A Longitudinal Study.

INTRODUCTION: We investigated whether secondhand smoke (SHS) exposure is associated with depressive symptoms in a population-based sample of children. METHODS: Never-smoking students from 29 French-language elementary schools in Greater Montréal, Canada, were followed from 5th to 11th grade (2005-2011) in five waves: 1 (5th grade), 2 (spring 6th grade), 3 (7th grade), 4 (9th grade), and 5 (11th grade). Associations between depressive symptoms and SHS exposure at home and in cars were examined in cross-sectional and longitudinal gamma generalized regression models adjusted for sex, maternal education, and neighborhood socioeconomic status. RESULTS: The sample comprised 1553 baseline never-smokers (mean [SD] age = 10.7 [0.5] years; 44% male; 89% French-speaking). SHS exposure at home and in cars was associated with higher depressive symptom scores in cross-sectional analyses pooled across grades and adjusted for demographics (B [95% confidence interval (CI)] = 0.041 [0.017 to 0.068] for home exposure; 0.057 [0.030 to 0.084] for car exposure). In longitudinal analyses from fifth to sixth grade, B (95% CI), adjusted for demographics and baseline depressive symptoms, was 0.042 (0.003 to 0.080) for home exposure and 0.061 (0.019 to 0.103) for car exposure. From sixth to seventh grade, B (95% CI) was 0.057 (0.003 to 0.110) for home exposure and 0.074 (0.015 to 0.133) for car exposure. SHS exposure at any age did not predict depressive symptoms 2 years later. CONCLUSIONS: SHS exposure is associated with depressive symptoms in young persons, both concurrently and 1 year later. This finding adds to the evidence base supporting that children should be protected from SHS exposure. IMPLICATIONS: SHS exposure has deleterious effects on physical health and results of this study raise concerns that such exposure might also affect the mental health of young persons. Clearly, protecting children from SHS in all locations is a critical public health priority. Although research is needed to determine if the association between SHS exposure and depressive symptoms is causal, continued implementation of smoking bans and educational efforts to discourage smoking in vehicles when children are present are warranted.

Type of e-liquid vaped, poly-nicotine use and nicotine dependence symptoms in young adult e-cigarette users: a descriptive study.

BACKGROUND: Data are lacking on type of e-liquid vaped among e-cigarette users. Further, few studies assess all sources of nicotine used by e-cigarette users to assess whether poly-nicotine use relates to nicotine dependence (ND). The objectives were to describe young adult e-cigarette users by: (i) type of e-liquid vaped; (ii) poly-nicotine use; (iii) ND symptoms; and (iv) attempts to quit conventional cigarettes. METHODS: Data were available in cycle 23 of a longitudinal investigation on the natural course of cigarette smoking and ND. A total of 775 young adults (44% male; mean (SD) age 30.5(1.0)) completed mailed self-report questionnaires in 2017-20. RESULTS: Of 775 participants, 149 (19.2%) reported past-year e-cigarette use. Overall, 55.0% of e-cigarette users had used cannabis-containing e-liquid (31.5% vaped cannabis e-liquid exclusively); 50.4% used nicotine-containing e-liquid (23.5% vaped nicotine e-liquid exclusively); and 39.9% used e-liquid without nicotine (8.7% vaped e-liquid without nicotine exclusively). Most e-cigarette users (82.6%) used other nicotine-containing products including conventional cigarettes (72.5%); 60.8% reported ND symptoms, rising to 79.4% among those who vaped nicotine-containing e-liquid. Finally, 29.0% tried to quit conventional cigarettes using e-cigarettes in the past-year, but only 16.7% found them helpful. CONCLUSIONS: E-cigarettes now appear to appeal to a broader market than smokers who want to quit. More than half of young adult e-cigarette users vaped cannabis-containing e-liquid in the past year while only one-quarter had used e-cigarettes to assist with cessation. Most e-cigarette users used multiple nicotine-containing substances (including combustible cigarettes) which were associated with reports of ND symptoms.

Depression symptoms and night eating in young adulthood.

PURPOSE: We estimated cross-sectional and longitudinal associations between depression symptoms and night eating in young adults. METHODS: Data were drawn from a longitudinal investigation of students age 12-13 years at inception in 1999-2000, in Montreal, Canada. Depression symptoms were measured with the Depressive Symptoms Scale (DSS) 20 times from age 12 to 17, and with the Major Depression Inventory (MDI) post-high school at ages 20 and 24. Night eating was measured at age 24. The association between depression symptoms and night eating was estimated in multivariable logistic regression models adjusted for sex, age and mother university-educated. RESULTS: 9% of 829 participants (n = 77) reported night eating. In cross-sectional analysis, the adjusted odds ratio (OR) estimate for MDI scores (range 0-50) was 1.04 (1.01, 1.07). In longitudinal analyses, the OR estimates were 1.75 (1.20, 2.55) for DSS scores (range 1-4) and 1.03 (1.002, 1.06) for the MDI. CONCLUSIONS: Depression symptoms are associated with night eating in young adults cross-sectionally and possibly longitudinally. Treatment of depression symptoms may be important in preventing night eating, a core symptom of the Night Eating Syndrome. LEVEL OF EVIDENCE: Level III, cohort analytic study.

Parental Cannabis Use Is Associated with Cannabis Initiation and Use in Offspring.

OBJECTIVES: To assess, before legalization in Canada, whether parental cannabis use is associated with initiation of use in adolescent offspring or with use in young-adult offspring. STUDY DESIGN: Data were available in 2 longitudinal studies in Montréal, Canada. In AdoQuest, 1048 parents with children in grade 6 reported past-year cannabis use. Cannabis initiation among offspring was measured in grade 7, 9, and/or 11. In the Nicotine Dependence in Teens study, cannabis use data were available for 584 participants (mean age 24 years) and their parents (ie, 542 offspring-mother pairs, 438 offspring-father pairs). The association between parental and offspring cannabis use was estimated using multivariable logistic regression in both studies. RESULTS: In AdoQuest, grade 6 never-users were 1.8 times more likely to initiate cannabis during high school if their parents reported past-year use. In the Nicotine Dependence in Teens study, the aORs (95% CI) for past-year cannabis use among adult offspring were not different for "mother uses cannabis" (2.8 [1.4-5.8]) or "father uses cannabis" (2.1 [1.2-3.8]). Participants with 1 or 2 cannabis-using parents were 1.7 and 7.1 times more likely to use cannabis, respectively, than participants with non-using parents. CONCLUSIONS: To enable informed decision-making about their own cannabis use, parents need to be aware that children of cannabis users are more likely to use cannabis in adolescence and young adulthood.

Sex Differences in Attaining Cigarette Smoking and Nicotine Dependence Milestones Among Novice Smokers.

There may be sex differences in the response to nicotine, according to findings of studies in animals; however, sex differences in the natural course of cigarette smoking and nicotine dependence are documented in few studies. Prevalent (n = 240 girls; n = 184 boys) and incident (n = 231 girls; n = 184 boys) cigarette smokers from the Nicotine Dependence in Teens Study were followed up to 5 years after first puff, from age 12 to 18 years (1999-2005). We used Cox proportional hazards models to compare time to development of 3 cigarette-use (i.e., whole cigarette; 100 cigarettes lifetime; regular smoking), and 3 nicotine-dependence symptom (i.e., "really need a cigarette"; mentally addicted; physically addicted) milestones across sex. Girls were at higher risk than boys of attaining all milestones; hazard ratios (95% confidence intervals) ranged from 1.35 (1.06, 1.72) for 100 cigarettes lifetime to 1.74 (1.44, 2.10) for "really need a cigarette." Among nonregular smokers, 26% (8%; 43%) and 25% (6%; 44%) more girls than boys reported "really need a cigarette" 1 and 2 years, respectively, after first puff. Preventive interventions may need adjustment to incorporate these findings. Additional research should clarify the relative contribution of biological and social underpinnings of these sex differences.

Determinants of sustained binge drinking in young adults.

BACKGROUND: Binge drinking occurs frequently among young adults, posing risks to health and safety. Little is known, however, about which drinkers continue to binge later into adulthood. We sought to identify predictors of sustained binge drinking behaviors in young adulthood. METHODS: Participants from the Nicotine Dependence in Teens (NDIT) cohort (n = 609, 53% female) completed self-report questionnaires in 20 survey cycles (SCs) during secondary school between 1999 and 2005, and in 2 postsecondary school SCs in 2007 to 2008 (SC 21; Mage = 20 years) and 2011 to 2012 (SC 22; Mage = 24 years). Participants reporting past-year binge drinking in both SCs 21 and 22 were categorized as sustainers (n = 517). Using multivariable logistic regression, we investigated 25 potential predictors of sustained binge drinking, binge-drinking frequency, and change in frequency over time among sustainers. RESULTS: Compared with stoppers, sustainers (85% of participants) were more likely to be younger, male, and to have no college/university education. Sustainers began drinking alcohol and binge drinking earlier, drank at least monthly during more secondary school grades, binged more frequently at age 20, and scored higher on impulsivity and novelty seeking in adolescence. Among sustainers, frequent binge drinkers were more likely to be male, to be nonstudents, to score higher on novelty seeking, and to have reported more depressive symptoms in adolescence. Sustainers who decelerated their binge frequency between SCs 21 and 22 were more likely to be female, to have achieved a higher level of education, and to report more depressive symptoms in SC 21. CONCLUSIONS: The determinants of sustained binge drinking are similar to predictors of binge drinking reported in the literature. Early identification of, and intervention with, youth who are impulsive, inclined toward novelty seeking, and who report higher levels of early sub clinical depressive symptoms might forestall their involvement in risky alcohol use.

Sustained waterpipe use among young adults.

INTRODUCTION: Waterpipe smoking is increasingly popular among North American youth. However, the extent to which waterpipe use is sustained over time is not known. The objective of this study was to describe the frequency and the predictors of sustained waterpipe use over 4 years among young adults. METHODS: Data were available in a prospective cohort investigation of 1,293 seventh-grade students recruited in a convenience sample of 10 secondary schools in Montreal, Canada, in 1999. Data on past-year waterpipe use were collected from 777 participants when they were age 20 years on average (in 2007-2008) and again when they were age 24 years (in 2011-2012) in mailed self-report questionnaires. Twenty potential predictors of sustained waterpipe use were tested, each in a separate multivariable logistic regression model. RESULTS: About 51% of 182 waterpipe users at age 20 reported waterpipe use 4 years later. Most sustained users (88%) smoked a waterpipe less than once a month. Parental smoking, being currently employed, less frequent cigarette smoking, and more frequent marijuana use were associated with sustained waterpipe use. CONCLUSIONS: Half of the young adults who used waterpipe during young adulthood reported use 4 years later. Young adults who sustain waterpipe use appear to do so as an activity undertaken occasionally to socialize with others.

Gender differences in reasons to quit smoking among adolescents.

It is well established that many adolescents who smoke want to quit, but little is known about why adolescents want to quit and if reasons to quit differ across gender. The objective of this study was to determine if reasons to quit smoking differ in boys and girls. Data on the Adolescent Reasons for Quitting (ARFQ) scale were collected in mailed self-report questionnaires in 2010-2011 from 113 female and 83 male smokers aged 14-19 years participating in AdoQuest, a longitudinal cohort study of the natural course of the co-occurrence of health-compromising behaviors in children. Overall, the findings indicate that reasons to quit in boys and girls appear to be generally similar, although this finding may relate to a lack of gender-oriented items in the ARFQ scale. There is a need for continued research to develop and test reasons to quit scales for adolescents that include gender-oriented items.

Effect of anti-smoking legislation on school staff smoking may dissipate over time.

This study describes student perceptions of school staff smoking before and after implementation of legislation prohibiting smoking on school grounds. Students completed self-report questionnaires before (grade 6) and after (grade 7, 9 and 11) the law. The percentage of students reporting that school staff smoked in areas where smoking is forbidden was 19%, 32% and 33% in grade 7, 9 and 11, respectively. The mean(SD) score for the frequency with which students saw school staff smoking decreased after the ban but increased thereafter [2.5(1.1), 1.9(1.0), 2.4(1.1) and 2.3(1.1)] in grade 6, 7, 9 and 11, respectively [F(2.861,1662.229) = 45.350, P < 0.001]. These data suggest that the effect of the law dissipated over time.

Identifying high school smokers likely to persist in smoking at age 31.

OBJECTIVE: Quitting smoking by the mid-30 s conveys important health benefits. Yet, although many smokers attempt to quit, few succeed. Identification of the characteristics of adolescent smokers most likely to continue smoking between ages 30 and 40 could help target early cessation efforts. Our objectives in this study were to (i) describe the course of smoking in a population-based sample of high school smokers into their 20 s and 30 s, and (ii) identify distal predictors of past-year cigarette smoking at age 31. METHODS: Data at ages 17 (in 11th grade), 20, 24 and 31 were drawn from a 20-year longitudinal study of students ages 12-13 at inception, from 10 high schools in Montréal, Canada. Associations between 11 smoking-related characteristics measured in 11th grade and past-year smoking at age 31 were estimated in multivariable logistic regression models. RESULTS: Among 244 11th grade smokers (67.4% female; 41% daily smokers), past-year smoking was reported by 71% at age 20, 68% at age 24, and 52% at age 31. Only 12% reported abstinence at ages 20, 24 and 31. Females were less likely than males to smoke at age 31. Parental smoking while the smoker was in 11th grade, use of other tobacco products, longer time since smoking onset, weekly or daily smoking, monthly cigarette consumption, and perceived nicotine addiction predicted past-year smoking at age 31. CONCLUSIONS: In addition to preventive interventions, cessation programs targeting novice smokers in high school as soon as they begin smoking, are warranted.

Assessing healthcare capacity crisis preparedness: development of an evaluation tool by a Canadian health authority.

Introduction: The COVID-19 pandemic presented health systems across the globe with unparalleled socio-political, ethical, scientific, and economic challenges. Despite the necessity for a unified, innovative, and effective response, many jurisdictions were unprepared to such a profound health crisis. This study aims to outline the creation of an evaluative tool designed to measure and evaluate the Vitalité Health Network's (New Brunswick, Canada) ability to manage health crises. Methods: The methodology of this work was carried out in four stages: (1) construction of an evaluative framework; (2) validation of the framework; (3) construction of the evaluative tool for the Health Authority; and (4) evaluation of the capacity to manage a health crisis. Results: The resulting evaluative tool incorporated 8 dimensions, 74 strategies, and 109 observable elements. The dimensions included: (1) clinical care management; (2) infection prevention and control; (3) governance and leadership; (4) human and logistic resources; (5) communication and technologies; (6) health research; (7) ethics and values; and (8) training. A Canadian Health Authority implemented the tool to support its future preparedness. Conclusion: This study introduces a methodological strategy adopted by a Canadian health authority to evaluate its capacity in managing health crises. Notably, this study marks the first instance where a Canadian health authority has created a tool for emergency healthcare management, informed by literature in the field and their direct experience from handling the SARS-CoV-2 pandemic.

Factors associated with cannabis use in early adolescence. / Facteurs associés à la consommation de cannabis au début de l'adolescence.

INTRODUCTION: We examined whether factors identified as associated with cannabis use at age 14 to 16 years are also associated with ever use at age 12. METHODS: Participants in the AdoQuest study (n = 1852) were recruited in 2005 from among Grade 5 students in 29 French-language elementary schools in Montréal, Canada. Self-report data were collected from participants in Grade 5 (spring 2005) and 6 (fall 2005 and spring 2006) and from parents/guardians in 2006/07. Inclusion in the analytic sample (n = 1076; mean age [SD] = 10.7 [0.5]) required data from participant and parental questionnaires and data on cannabis use in Grade 6 (mean age [SD] = 11.7 [0.4]). We estimated associations between ever use at age 12 with 33 potential correlates, separately in unadjusted and adjusted logistic regression models. RESULTS: Fifty-three participants (4.9%) reported ever use at age 12. Factors associated with higher odds of ever use included older age, identifying as male, lower household income, more weekly spending money, ever tried cigarettes or other tobacco products, ever drank alcohol or binge drank, ever gambled, friends or siblings smoke cigarettes, greater nicotine dependence, higher depressive symptoms and greater impulsivity. Protective factors included higher levels of parental/guardian monitoring and greater self-esteem and school connectedness. CONCLUSION: Factors associated with cannabis use at later ages are also associated with ever use at age 12. Our findings suggest that surveillance for and interventions to prevent cannabis use are warranted before age 12.

Canadian clinical capacity for fetal alcohol spectrum disorder assessment, diagnosis, disclosure and support to children and adolescents: a cross-sectional study.

OBJECTIVE: Canadian fetal alcohol spectrum disorder (FASD) guidelines encourage an age-specific interdisciplinary diagnostic approach. However, there is currently no standard-of-care regarding FASD diagnosis disclosure and few studies document Canadian FASD clinical capacity. Our objectives were to describe clinical capacity (defined as skills and resources) for FASD assessment, diagnosis, disclosure and support in Canada. DESIGN, SETTING AND PARTICIPANTS: Data were drawn from the CanDiD study, a cross-sectional investigation of Canadian FASD clinical capacity. Forty-one clinics participated in the study. Data were collected in 2021 on the number and types of health professionals included in the assessment and diagnostic teams, the presence (or absence) of a minor patient when the FASD diagnosis is disclosed to parents/guardians, who is responsible for the diagnosis disclosure, the use of explanatory tools, and the types of support/counselling services available. The proportion of clinics that follow the Canadian interdisciplinary diagnostic guidelines by age group is described among participating clinics. RESULTS: Overall, 21, 13 and 7 specialised FASD clinics were in Western/Northern, Central and Atlantic Canada, respectively. The number of referrals per year surpassed the number of diagnostic assessments completed in all regions. Approximately, 60% of clinics who diagnosed FASD in infants and preschool children (n=4/7 and 15/25, respectively) followed the interdisciplinary guidelines compared with 80% (n=32/40) in clinics who diagnosed school-aged children/adolescents. Diagnostic reporting practices were heterogeneous, but most used an explanatory tool with children/adolescents (67%), offered support/counselling (90-95%) and used case-by-case approach (80%) when deciding who would disclose the diagnosis to the child/adolescent and when. CONCLUSIONS: Limited diagnostic capacity and lack of FASD resources across Canada highlights a critical need for continued FASD support. This study identifies gaps in assessment, diagnosis and reporting practices for FASD in children/adolescents across Canada.

Who mixes tobacco with cannabis and does mixing relate to nicotine dependence?

BACKGROUND: Cannabis users who mix tobacco with cannabis are exposed to nicotine in the tobacco. We identified characteristics of young adult cannabis users who mix and investigated whether mixing frequency is associated with nicotine dependence (ND). METHODS: Data were collected in self-report questionnaires in 2017-20 from 788 young adults (44% male; mean (SD) age 30.6 (1.0) years) participating in a longitudinal investigation of the natural course of ND. Using multivariable logistic regression, we assessed whether any of 16 sociodemographic, lifestyle, psychosocial or other characteristics were associated with mixing among 313 past-year cannabis users. We also assessed whether mixing frequency was associated with ND among 289 past-year cannabis users who had ever smoked cigarettes controlling for age, sex, and other sources of nicotine (i.e., number of cigarettes smoked, other tobacco products, second-hand smoke exposure). RESULTS: Of 788 participants, 40 % (n = 313) reported past-year cannabis use. Of these, 150 (48 %) reported mixing. Younger age, lower education and income, past-year cigarette use, use of other tobacco products and illicit drugs, poor coping skills and gambling were associated with mixing. Number of ICD-10 ND criteria endorsed was associated with mixing < weekly (b(95 % CI) = 0.3(0.02,0.7)) and weekly/daily (0.5(0.1,0.9)) after controlling for other sources of nicotine. CONCLUSION: Mixing is associated with ND and therefore may threaten tobacco control efforts by rendering quitting cigarette smoking more difficult among smokers who mix tobacco with cannabis. Mixing tobacco with cannabis should be considered as an additional source of nicotine exposure in studies of ND in young people.

Associations of Quantity Smoked and Socioeconomic Status With Smoke-Free Homes and Cars Among Daily Smokers.

INTRODUCTION: An association between socioeconomic status (SES) and smoke-free private spaces among smokers could be due to heavier smoking among low SES smokers. We assessed whether quantity smoked or SES are independently associated with smoke-free homes or cars in daily smokers. METHOD: Data were drawn from a cross-sectional telephone survey (2011-2012) of 750 daily smokers age ≥18 years in Quebec, Canada (45% response). Multivariable logistic regression was used to model the independent association between (a) number of cigarettes smoked per day, and (b) each of educational attainment, annual household income, or active employment status and smoke-free homes or cars. RESULTS: Participants were 41.0 years old on average, 57% were female. Median (IQR) number of cigarettes smoked per day was 14 (10, 20). Forty-eight percent of participants reported smoke-free homes; 34% reported smoke-free cars. Quantity smoked was strongly associated with both smoke-free homes and cars. Income and education (but not actively employed) were associated with smoke-free homes. None of the SES indicators were associated with smoke-free cars. CONCLUSIONS: Interventions targeting smokers to promote smoke-free homes and cars should incorporate components to help smokers reduce quantity smoked or preferably, to quit. Interventions targeting smoke-free homes will also need to address SES inequalities by education and income. Our data suggest that reduction in quantity smoked may help smokers reduce SHS exposure in cars, but that an inequality lens may not be relevant.

Natural course of co-use of alcohol and cannabis in adolescents and young adults in Montréal, Canada.

OBJECTIVE: Little is known about changes in alcohol and cannabis co-use over time in adolescents and young adults. We sought to describe the natural course of alcohol and cannabis co-use from age 12 to 17 and 20 to 31 and to describe frequent (i.e., ≥ once/month) binge drinking (i.e., ≥ 5 drinks/occasion) and cannabis use from age 20 to 31. METHOD: Data were drawn from two longitudinal studies conducted in Montréal, Canada: AdoQuest (n = 1,852) and the Nicotine Dependence in Teens (NDIT) study (n = 1,293). Complete data on alcohol and cannabis were available for 620 12-17-year-olds (58% female) followed from 2005 to 2011 in AdoQuest, and 673 20-31-year-olds (56% female) followed from 2007 to 2020 in NDIT. We reported proportions of co-use, exclusive drinking ("drinking"), exclusive cannabis use ("cannabis use"), frequent co-use, frequent binge drinking, and frequent cannabis use by age and sex. RESULTS: Co-use rose from 2% at age 12-13 to 23% at age 17, was stable at 44% at age 20 and 24, and then decreased to 37% at age 31. Drinking rose from 20% to 51%, and cannabis use was consistently rare (< 2%). During young adulthood, frequent co-use declined from 21% at age 20 to 12% at age 31, and frequent binge drinking declined from 29% at age 20 to 22% at age 31. Frequent cannabis use increased from 6% at age 20 to 11% at age 31. CONCLUSIONS: Alcohol and cannabis use should be studied as time-varying behaviors. Co-use patterns should be monitored over time in this population. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The Natural Course of Cigarette Smoking among Adolescent Daily Smokers in France and Quebec.

OBJECTIVE: To describe the natural course of cigarette smoking and nicotine dependence (ND) over 1-year in daily smokers ages 15 to 17 living in different social contexts. METHOD: Cigarette smoking and ND indicators were measured at baseline and 3- and 12-months thereafter among 95 daily smokers with a total of 123 observations from the Nicotine Dependence in Teens (NDIT) Study in Quebec, Canada, and in 111 daily smokers from the TABagisme chez les ADOlescents (TABADO) Study in Lorraine, France. RESULTS: NDIT and TABADO participants initiated smoking a mean (SD) of 3.9 (1.6) and 3.7 (2.0) years prior to baseline, respectively. Despite baseline differences in age, sex, age at initiation, number of cigarettes smoked per day and social context, 85% of participants in both samples reported cravings and responded "yes" to "felt like you really need a cigarette". Mean (SD) number of cigarettes smoked per day increased from 9.4 (8.1) to 11.8 (8.0) over 1 year in NDIT (adjusted mean difference (95% CI) = 2.4 (0.8, 3.0)), and from 11.5 (6.5) to 13.5 (6.7) in TABADO (adjusted mean difference (95% CI) = 2.0 (0.8, 3.1)). However, most ND indicators in both samples were stable over time and cessation was infrequent. CONCLUSION: Despite notable differences across samples, the natural course of cigarettes smoked per day, ND symptoms and cessation was similar, suggestive of an underlying biologic rather than social process. To quit, adolescents who smoke daily will likely need (pharmacologic) intervention to counter the biological mechanisms underpinning ND, as well as complementary strategies targeting the social context such as creating social environments favoring cessation success.

Does use of other tobacco products change when cigarette smoking status changes: A descriptive study of young adults.

BACKGROUND: Whether polytobacco use or nicotine dependence (ND) change when cigarette smoking status changes in young adults is an understudied issue. Our objective was to describe use of other tobacco products (OTPs) and ND according to change in cigarette smoking status over four years in young adults. METHODS: We drew data from a longitudinal study of 1294 adolescents age 12-13 at inception in 1999-2000 and followed into young adulthood. Among 790 participants with data at age 20 and 24, 22% had never smoked cigarettes; 37% were "sustained smokers"; 9% were "relapsers"; 10% had quit 1-3 years ago; and 22% had quit ≥4 years ago. We described past-year OTP (i.e., cigars/cigarillos, waterpipe, sundry tobacco products (i.e., pipe, bidis, chewing tobacco, snuff)) use and ND over 4 years in these groups. RESULTS: At age 20, sustained smokers reported using a mean(SD) of 1.1(0.9) OTP in the past-year; relapsers reported 0.5(0.6); shorter-term quitters reported 0.9(0.7); longer-term quitters reported 0.3(0.6); and never smokers reported 0.2(0.4). There was no change in OTP use or ND in never smokers and longer-term quitters. Shorter-term quitters reduced the number of OTPs by -0.5(95% confidence interval: -0.7,-0.3) on average over 4 years; sustained smokers decreased by -0.2(-0.3,-0.1). Relapsers increased by 0.6(0.4,0.7) on average. CONCLUSIONS: OTP use and ND were stable in early adulthood among never smokers, sustained smokers and longer-term quitters, but fluctuated in parallel with stopping and starting to smoke. Research is needed to ascertain the underpinnings of these fluctuations and whether they help or hinder cessation.

Intensity and frequency of physical activity and high blood pressure in adolescents: A longitudinal study.

Despite limited evidence on the association between physical activity (PA) and blood pressure (BP) in youth, experts recommend that adolescents engage regularly in moderate-to-vigorous PA. We examined the relationships between PA intensity and frequency and the likelihood of having high BP in a population-based cohort of adolescents from Montréal, Canada. PA was self-reported every 3 months from grade 7 to 11, and BP was measured at ages 12.8, 15.2, and 17.0 years on average. We analyzed data from 993 participants (mean [SD] age = 16.0 [1.0], 51.6% female) with BP data at ages 15.2 and/or 17.0 years, using pooled ordinal logistic regression. BP (normal/elevated/hypertensive range) was the outcome, and past-year PA intensity and frequency were potential predictors. Eight percent of participants had elevated BP (120-129/<80), and 3.2% had BP in the hypertensive range (≥130/≥80). Participants engaged in a median (interquartile range) of 7.0 (4.5, 9.3) and 5.5 (2, 10.8) moderate and vigorous PA sessions/week, respectively. After adjusting for age, sex, mother's education, use of alcohol and cigarette consumption, engaging in PA more intense than light during the previous year was associated with a lower odds of having BP in the hypertensive range (ORs [95% CIs] = 0.93 [0.88, 0.97] to 0.97 [0.94, 0.99]). The relationships were not altered by adjusting for BMI. Our findings support recommendations that adolescents engage in at least moderate PA on a regular basis to prevent development of BP in the hypertensive range.