Short-Term Natural Course of Depressive Symptoms and Family-Related Stress in Adolescents After Separation From Father.

Objective: To determine if separation from a father is associated with short-term changes in mental health or substance use in adolescents.

Methods: Every 3 months, during a 5-year period, we followed 1160 Grade 7 students participating in the Nicotine Dependence in Teens Study who were living with both parents. Participants who reported not living with their father for 6 or more consecutive months during follow-up were categorized as separated from father.

Genetic variants and early cigarette smoking and nicotine dependence phenotypes in adolescents.

Background: While the heritability of cigarette smoking and nicotine dependence (ND) is well-documented, the contribution of specific genetic variants to specific phenotypes has not been closely examined. The objectives of this study were to test the associations between 321 tagging single-nucleotide polymorphisms (SNPs) that capture common genetic variation in 24 genes, and early smoking and ND phenotypes in novice adolescent smokers, and to assess if genetic predictors differ across these phenotypes.

Methods: In a prospective study of 1294 adolescents aged 12-13 years recruited from ten Montreal-area secondary schools, 544 participants who had smoked at least once during the 7-8 year follow-up provided DNA.

Lithium dosing and serum concentrations across the age spectrum: from early adulthood to the tenth decade of life.

Objectives: Little is known about how lithium should be dosed to achieve therapeutic but safe serum concentrations in older adults. In this paper, we investigate how the lithium dose-concentration ratio changes across the lifespan.

Methods: This was a cross-sectional analysis of 63 current lithium users aged 20-95 years using data from McGLIDICS (the McGill Geriatric Lithium-Induced Diabetes Insipidus Clinical Study).

Is environmental temperature related to renal symptoms, serum lithium levels, and other laboratory test results in current lithium users?

Objective: Lithium continues to be an important mood disorder treatment. Although patients exposed to higher environmental temperatures may have serum lithium level elevations due to dehydration, there is conflicting data in the literature. In addition, no study has assessed the association between temperature and other renal laboratory tests and symptoms in lithium users.

Association Between Childhood Sleep-Disordered Breathing and Disruptive Behavior Disorders in Childhood and Adolescence.

We examined the association between sleep-disordered breathing (SDB) and disruptive behavior disorders in 605 children participating in a population-based cohort study. Nineteen percent of children snored (sometimes or often) and 10% had obstructive sleep apnea (OSA) symptoms. Thirteen percent had an ADHD diagnosis or symptoms and 5-9% had behavioral problems or a conduct disorder.

Cohort Profile: The Nicotine Dependence in Teens (NDIT) Study.

The Nicotine Dependence in Teens (NDIT) study is a prospective cohort investigation of 1294 students recruited in 1999-2000 from all grade 7 classes in a convenience sample of 10 high schools in Montreal, Canada. Its primary objectives were to study the natural course and determinants of cigarette smoking and nicotine dependence in novice smokers. The main source of data was self-report questionnaires administered in class at school every 3 months from grade 7 to grade 11 (1999-2005), for a total of 20 survey cycles during high school education.

The McGill Geriatric Lithium-Induced Diabetes Insipidus Clinical Study (McGLIDICS).

Objective: Despite being a common and potentially serious condition, nephrogenic diabetes insipidus (NDI) remains poorly understood in older lithium users. Our main objective was to compare the prevalence of NDI symptoms and decreased urine osmolality ([UOsm] < 300 milli-Osmoles [mOsm/kg]) among geriatric and adult lithium users. We also assessed NDI symptoms, serum sodium (Na+), and urine specific gravity (USG) as possible surrogate measures of decreased UOsm, and ascertained whether potential etiologic factors independently correlated with decreased UOsm.

Measurement invariance of the depressive symptoms scale during adolescence.

Background: This study examined (1) the factor structure of a depressive symptoms scale (DSS), (2) the sex and longitudinal invariance of the DSS, and (3) the predictive validity of the DSS scale during adolescence in terms of predicting depression and anxiety symptoms in early adulthood.

Methods: Data were drawn from the Nicotine Dependence in Teens (NDIT) study, an ongoing prospective cohort study of 1,293 adolescents.

Results: The analytical sample included 527 participants who provided complete data or had minimal missing data over follow-up.

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.

Symptoms of depression are longitudinally associated with sedentary behaviors among young men but not among young women.

Objective: A habitual sedentary lifestyle is associated with adverse health outcomes; however, the predictors of sedentary behaviors have not been sufficiently explored to inform the development and delivery of effective interventions to reduce sedentary behaviors. This study examined whether reports of symptoms of depression could predict weekly time spent in sedentary behaviors (i.e.

The association between CHRN genetic variants and dizziness at first inhalation of cigarette smoke.

Numerous single nucleotide polymorphisms (SNPs) in multiple nicotinic receptor genes (CHRN) are associated with smoking. However few studies have examined the association between CHRN SNPs and subjective responses to smoking in adolescents which may relate to sustained smoking, such as dizziness at first inhalation. The objective of this study was to investigate the association between 61 SNPs in eight CHRN genes (CHRNA3, CHRNA4, CHRNA5, CHRNA6, CHRNA7, CHRNB2, CHRNB3, CHRNB4) and dizziness at first inhalation.

Heterogeneity of Depressive Symptom Trajectories through Adolescence: Predicting Outcomes in Young Adulthood.

Objective: This study describes developmental trajectories of depressive symptoms in adolescents and examines the association between trajectory group and mental health outcomes in young adulthood.

Methods: Depressive symptoms were self-reported every three months from grade seven through grade 11 by 1293 adolescents in the Nicotine Dependence in Teens (NDIT) study and followed in young adulthood (average age 20.4, SD=0.

Linking depression symptom trajectories in adolescence to physical activity and team sports participation in young adults.

Objective: The objective of this study is to examine depressive symptom trajectories during adolescence as predictors of physical activity (PA) in young adulthood.

Methods: Adolescents residing in Montreal, Canada (n=860) reported their depressive symptoms every 3-4 months during high school in 20 data collections. Three years later, participants reported engaging in moderate and vigorous intensity PA and team sports participation.

The association between past and current physical activity and depressive symptoms in young adults: a 10-year prospective study.

Purpose: The objectives of this study were to assess (1) the longitudinal associations of past moderate-to-vigorous physical activity (MVPA) and involvement in team sports during secondary school with depressive symptoms in early adulthood, and (2) the cross-sectional associations of current MVPA and involvement in team sports with depressive symptoms during young adulthood.

Methods: Data were drawn from the Nicotine Dependence in Teens study, which is an ongoing prospective cohort study of 1293 adolescents aged 12-13 years at baseline (52% female). Data analyses involved latent growth curve modeling and multiple hierarchical linear regression models.

The association between parental history of diagnosed mood/anxiety disorders and psychiatric symptoms and disorders in young adult offspring.

Background: Parental history of mood or anxiety disorders is one of the strongest and most consistent risk factors for the development of these disorders in offspring. Gaps remain however in our knowledge of whether maternal or paternal disorders are more strongly associated with offspring disorders, and whether the association exists in non-clinical samples. This study uses a large population-based sample to test if maternal or paternal history of mood and/or anxiety disorders increases the risk of mood and/or anxiety disorders, or symptoms of specific anxiety disorders, in offspring.

Comorbidity of migraine and mood episodes in a nationally representative population-based sample.

Objective: To examine the lifetime comorbidity of migraine with different combinations of mood episodes: (1) manic episodes alone; (2) depressive episodes alone; (3) manic and depressive episodes; (4) controls with no lifetime history of mood episodes, as well as sociodemographic and clinical correlates of migraine for each migraine-mood episode combination.

Background: Migraine has been found to be comorbid with bipolar disorder and major depressive disorder in clinical and population-based samples. However, variability in findings across studies suggests that examining mood episodes separately may be fruitful in determining which of these mood episodes are specifically associated with migraine.

Common stressful life events and difficulties are associated with mental health symptoms and substance use in young adolescents.

Background: Stressful life events are associated with mood disorders in adults in clinical settings. Less described in the literature is the association between common life stressors and a wide range of psychopathology in young adolescents. This study uses a large non-clinical sample of young adolescents to describe the associations among worry or stress about common life events/difficulties, mental health and substance use.