Publications (114) View all
-
Article: Exploring the Association Between Well-Being and Psychopathology in Adolescents.
[show abstract] [hide abstract]
ABSTRACT: Promotion of mental well-being and prevention of emotional and behavioral problems are suggested to go hand in hand. The present study examined the association between subjective well-being (SWB) and psychopathology and investigated the etiology of this association in a large population-based cohort study of adolescent twins (n = 9,136) and their non-twin siblings (n = 1,474) aged 12-20 years. Phenotypic, genetic, and environmental correlations between SWB and psychopathology were obtained from multivariate genetic modeling conditional on sex. An SWB factor score was used based on measures of subjective happiness, satisfaction with life, and quality of life. Psychopathology was obtained from all syndrome and broad-band scales of the Dutch version of the ASEBA Youth Self Report. Males reported significantly higher levels of SWB than females. Females reported significantly more internalizing problems while males report significantly higher levels of externalizing behavior. In both sexes, significant negative associations were found between SWB and psychopathology, with the strongest associations seen for SWB and the YSR syndrome scale anxious/depression behavior. The observed associations were primarily explained by genetic correlations while non-shared environmental influences were mainly domain specific. The genetic liability to lower levels of SWB are indicative of a genetic liability to higher levels of psychopathology, suggesting that it might be feasible to screen for emotional and behavioral problems before clear signs are present by screening on indices of subjective well-being.Behavior Genetics 03/2013; · 2.52 Impact Factor -
Article: Increases in alcohol consumption in women and elderly groups: evidence from an epidemiological study.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: In most Western countries, alcohol consumption continues to increase, specifically among women and older adults. Insight into these trends may aid intervention strategies. Here we present data on alcohol consumption by age and sex as well as associations between alcohol use and demographic lifestyle/traits. The data are from a large (N>16,000) population-based Dutch sample, ascertained based on the presence of twins in the family. METHODS: A set of 16 indicators of normative and problematic alcohol use was assessed in participants of the Netherlands Twin Register between 2009--2012 (ages 18--97; 6,052 men; 10,535 women). Alcohol consumption and demographic/lifestyle traits, including educational attainment, work-related/financial stress, urbanization, religiousness, smoking/cannabis initiation, and BMI were described by age and sex. Associations were examined by regressing aspects of alcohol use on age, sex, their interaction, and demographic/lifestyle variables. RESULTS: Age, sex, and initiation of cigarette and cannabis use were the most important predictors of alcohol use. Frequency of alcohol use was lowest between 18--25 years, with 3.2% of men and .6% of women drinking 6--7 times/week, and highest above age 65 years, with 30.6-32.7% of men and 20.2-22.0% of women drinking 6--7 times/week. Women consumed the lowest quantities of alcohol between 25--45 years, with a 5.7-5.9% prevalence of excessive drinking (>14 glasses/week), and the largest quantities between 55--65 years (15.5% excessive drinkers). Age at alcohol initiation, onset of regular drinking, and first alcohol intoxication were lowest between ages 18--25 years and highest above age 65 years. Among older participants, men initiated alcohol use and regular drinking earlier, and had lower age at first intoxication than women, but among young adults, no sex differences were observed. CONCLUSIONS: Alcohol consumption was high in the elderly Dutch population, especially among women. Alcohol initiation, onset of regular drinking, and first alcohol intoxication occur at increasingly younger ages, and the previous gap between men and women in age at alcohol initiation, onset of regular drinking, and first alcohol intoxication has closed almost entirely. Heavy alcohol use was most strongly predicted by older age, sex (male), and initiation of smoking and cannabis use.BMC Public Health 03/2013; 13(1):207. · 2.00 Impact Factor -
Article: Separating the domains of oppositional behavior: comparing latent models of the conners' oppositional subscale.
[show abstract] [hide abstract]
ABSTRACT: Although oppositional defiant disorder (ODD) is usually considered the mildest of the disruptive behavior disorders, it is a key factor in predicting young adult anxiety and depression and is distinguishable from normal childhood behavior. In an effort to understand possible subsets of oppositional defiant behavior (ODB) that may differentially predict outcome, we used latent class analysis of mother report on the Conners' Parent Rating Scales Revised Short Forms (CPRS-R:S). Data were obtained from mother report for Dutch twins (7 years old, n = 7,597; 10 years old, n = 6,548; and 12 years old, n = 5,717) from the Netherlands Twin Registry. Samples partially overlapped at ages 7 and 10 years (19% overlapping) and at ages 10 and 12 years (30% overlapping), but not at ages 7 and 12 years. Oppositional defiant behavior was measured using the six-item Oppositional subscale of the CPRS-R:S. Multilevel LCA with robust standard error estimates was performed using the Latent Gold program to control for twin-twin dependence in the data. Class assignment across ages was determined and an estimate of heritability for each class was calculated. Comparisons with maternal report Child Behavior Checklist (CBCL) scores were examined using linear mixed models at each age, corrected for multiple comparisons. The LCA identified an optimal solution of four classes across age groups. Class 1 was associated with no or low symptom endorsement (69-75% of the children); class 2 was characterized by defiance (11-12%); class 3 was characterized by irritability (9-11%); and class 4 was associated with elevated scores on all symptoms (5-8%). Odds ratios for twins being in the same class at each successive age point were higher within classes across ages than between classes. Heritability within the two "intermediate" classes was nearly as high as for the class with all symptoms, except for boys at age 12. Children in the Irritable class were more likely to have mood symptoms on the CBCL scales than children in the Defiant class but demonstrated similar scores on aggression and externalizing scales. Children in the All Symptoms class were higher in both internalizing and externalizing scales and subscales. The LCA indicates four distinct latent classes of oppositional defiant behavior, in which the distinguishing feature between the two intermediate classes (classes 2 and 3) is the level of irritability and defiance. Implications for the longitudinal course of these symptoms, association with other disorders, and genetics are discussed.Journal of the American Academy of Child and Adolescent Psychiatry 02/2013; 52(2):172-183.e8. · 4.98 Impact Factor -
Article: Developmental prediction model for early alcohol initiation in dutch adolescents.
[show abstract] [hide abstract]
ABSTRACT: Objective: Multiple factors predict early alcohol initiation in teenagers. Among these are genetic risk factors, childhood behavioral problems, life events, lifestyle, and family environment. We constructed a developmental prediction model for alcohol initiation below the Dutch legal drinking age (16 years), elaborating on the pathways identified by earlier studies.Method: A set of 22 prospectively measured variables, previously associated with alcohol initiation, was examined by path analytic techniques in a sample of 1,804 Dutch adolescents (ages 13-15 years, 56% girls). The predictors included genetic risk for alcohol initiation and behavioral/emotional problems; prenatal and childhood stressors and childhood behavioral/emotional problems; and adolescent behavioral/emotional problems, lifestyle, family functioning, and peerrelated factors.Results: The model explained 66% of variance in early alcohol initiation. Subjects at higher genetic risk of alcohol initiation who had friends who drank alcohol and who had started smoking at an early age were at increased risk of initiating alcohol use before age 16. Behavioral (externalizing) problems were moderately and indirectly associated with early alcohol initiation, and emotional (internalizing) problems were marginally and indirectly associated with alcohol initiation.Conclusions: The Netherlands has relatively lenient alcohol laws.In this permissive environment, early alcohol initiation is explained by alcohol-specific genetic risk, smoking initiation, and peer-related factors, whereas behavioral and emotional problems are only indirectly related to early alcohol initiation. (J. Stud. Alcohol Drugs, 74, 59-70, 2013).Journal of studies on alcohol and drugs 01/2013; 74(1):59-70. · 2.25 Impact Factor -
Article: Genetic Variation at the TPH2 Gene Influences Impulsivity in Addition to Eating Disorders.
[show abstract] [hide abstract]
ABSTRACT: Genes are involved in eating disorders (EDs) and self-induced vomiting (SV), a key symptom of different types of EDs. Perfectionism and impulsivity are potential risk factors for EDs. TPH2 (tryptophan hydroxylase 2) SNP rs1473473 was previously associated with anorexia nervosa and EDs characterized by SV. Could perfectionism or impulsivity be underlying the association between rs1473473 and EDs? Genetic association between TPH2 SNP rs1473473 and perfectionism or impulsivity was first evaluated in a random control group (N = 512). The associations obtained in this control group were subsequently tested in a group of patients with an ED (N = 267). The minor allele of rs1473473 (OR = 1.49) was more frequent in impulsive controls, but also in impulsive patients with an ED (OR = 1.83). The largest effect was found in the patients with an ED characterized by SV (OR = 2.51, p = 0.02). Genetic variation at the TPH2 gene appeared to affect impulsivity which, in turn, might predispose to the SV phenotype.Behavior Genetics 12/2012; · 2.52 Impact Factor
