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Alaattin Erkanli

Publications and source records attributed to Alaattin Erkanli.

15 recordsLinked to original sources

Reading problems, psychiatric disorders, and functional impairment from mid- to late adolescence.

OBJECTIVE: To examine psychiatric morbidity and functional impairment of adolescents with and without poor reading skills during mid- to late adolescence. METHOD: The sample consisted of 188 adolescents, 94 with poor reading skills and 94 with typical reading skills, screened from a larger sample in the public schools at age 15. To assess psychiatric disorders, participants were assessed annually with the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Epidemiologic Version (up to 4.5 years; maximum age, 20 years). Functional impairment was assessed with the Child and Adolescent Functional Assessment Scale. RESULTS: Adolescents with poor reading skills evidenced higher rates of current attention-deficit/hyperactivity, affective, and anxiety disorders, particularly social phobia and generalized anxiety disorder. Anxiety disorders but not affective disorders were related to reading status after controlling for attention-deficit/hyperactivity disorder. Adolescents with poor reading evidenced more functional impairment across multiple areas than youths with typical reading skills, even after considering the presence of comorbid attention-deficit/hyperactivity disorder. CONCLUSIONS: The increased psychiatric morbidity and functional impairment of adolescents with reading problems highlight the importance of developing interventions that help these youths address reading deficits and associated vulnerabilities during the last years of secondary school.

Adolescent↗

Bayesian semi-parametric ROC analysis.

This paper describes a semi-parametric Bayesian approach for estimating receiver operating characteristic (ROC) curves based on mixtures of Dirichlet process priors (MDP). We address difficulties in modelling the underlying distribution of screening scores due to non-normality that may lead to incorrect choices of diagnostic cut-offs and unreliable estimates of prevalence of the disease. MDP is a robust tool for modelling non-standard diagnostic distributions associated with imperfect classification of an underlying diseased population, for example, when a diagnostic test is not a gold standard. For posterior computations, we propose an efficient Gibbs sampling framework based on a finite-dimensional approximation to MDP. We show, using both simulated and real data sets, that MDP modelling for ROC curve estimation closely parallels the frequentist kernel density estimation (KDE) approach.

Adolescent↗

Test-Retest Reliability of the Preschool Age Psychiatric Assessment (PAPA).

OBJECTIVE: To examine the test-retest reliability of a new interviewer-based psychiatric diagnostic measure (the Preschool Age Psychiatric Assessment) for use with parents of preschoolers aged 2 to 5 years. METHOD: A total of 1,073 parents of children attending a large pediatric clinic completed the Child Behavior Checklist 1 1/2-5. For 18 months, 193 parents of high scorers and 114 parents of low scorers were interviewed on two occasions an average of 11 days apart. RESULTS: Estimates of diagnostic reliability were very similar to those obtained from interviews with parents of older children and adults, with kappas ranging from 0.36 to 0.79. Test-retest intraclass correlations for DSM-IV syndrome scale scores ranged from 0.56 to 0.89. There were no significant differences in reliability by age, sex, or race (African American versus non-African American). CONCLUSIONS: The Preschool Age Psychiatric Assessment provides a reasonably reliable standardized measure of DSM-IV psychiatric symptoms and disorders in preschoolers for use in both research and clinical service evaluations of preschoolers as young as 2 years old.

Child Behavior Disorders↗

Is there an epidemic of child or adolescent depression?

BACKGROUND: Both the professional and the general media have recently published concerns about an 'epidemic' of child and adolescent depression. Reasons for this concern include (1) increases in antidepressant prescriptions, (2) retrospective recall by successive birth cohorts of adults, (3) rising adolescent suicide rates until 1990, and (4) evidence of an increase in emotional problems across three cohorts of British adolescents. METHODS: Epidemiologic studies of children born between 1965 and 1996 were reviewed and a meta-analysis conducted of all studies that used structured diagnostic interviews to make formal diagnoses of depression on representative population samples of participants up to age 18. The effect of year of birth on prevalence was estimated, controlling for age, sex, sample size, taxonomy (e.g., DSM vs. ICD), measurement instrument, and time-frame of the interview (current, 3 months, 6 months, 12 months). RESULTS: Twenty-six studies were identified, generating close to 60,000 observations on children born between 1965 and 1996 who had received at least one structured psychiatric interview capable of making a formal diagnosis of depression. Rates of depression showed no effect of year of birth. There was little effect of taxonomy, measurement instrument, or time-frame of interview. The overall prevalence estimates were: under 13, 2.8% (standard error (SE) .5%); 13-18 5.6% (SE .3%); 13-18 girls: 5.9% (SE .3%); 13-18 boys: 4.6% (SE .3%). CONCLUSIONS: When concurrent assessment rather than retrospective recall is used, there is no evidence for an increased prevalence of child or adolescent depression over the past 30 years. Public perception of an 'epidemic' may arise from heightened awareness of a disorder that was long under-diagnosed by clinicians.

Adolescent↗

Lifetime trauma exposure in veterans with military-related posttraumatic stress disorder: association with current symptomatology.

OBJECTIVE: This study examined whether trauma exposure before, during, and/or after military service contributed to current levels of post-traumatic stress disorder (PTSD) and adjustment. Further, we investigated whether trauma exposure before military service was mediated or moderated by military trauma in its effects on current PTSD and adjustment. METHOD: In this retrospective study, archival data from the medical records of 422 male veterans diagnosed with PTSD between December 2001 and July 2004 at a Veterans Administration Medical Center PTSD clinic were analyzed. Measures included the Clinician-Administered PTSD Scale interview as well as self-report measures assessing trauma history, health problems, and general psychopathology (including PTSD). RESULTS: Findings indicated that nonmilitary-related trauma was prevalent in this sample (90%). Regression analyses for PTSD symptom severity revealed that age, greater combat exposure, and a history of physical assault after military service were significantly associated with more severe PTSD symptoms. Childhood physical abuse, adult sexual trauma, and a history of being physically assaulted during military service were also significantly associated with PTSD symptom severity. Mediational analyses indicated that childhood trauma was associated with both adult trauma and increased symptomatology on various outcome measures. Moderational analyses indicated that adult trauma exposure moderated the effect of childhood trauma exposure on health complaints. CONCLUSIONS: Results suggest that several variables, including age, greater combat exposure, and premilitary and postmilitary traumas, are associated with increased PTSD symptomatology. This finding underscores the importance of conducting a thorough assessment of trauma when diagnosing PTSD.

Adaptation, Psychological↗

Application of Bayesian inference using Gibbs sampling to item-response theory modeling of multi-symptom genetic data.

Several "genetic" item-response theory (IRT) models are fitted to the responses of 1086 adolescent female twins to the 33 multi-category item Mood and Feeling Questionnaire relating to depressive symptomatology in adolescence. A Markov-chain Monte Carlo (MCMC) algorithm is used within a Bayesian framework for inference using Gibbs sampling, implemented in the program WinBUGS 1.4. The final model incorporated separate genetic and non-shared environmental traits ("A and E") and item-specific genetic effects. Simpler models gave markedly poorer fit to the observations judged by the deviance information criterion (DIC). The common genetic factor showed major loadings on melancholic items, while the environmental factor loaded most highly on items relating to self-deprecation. The MCMC approach provides a convenient and flexible alternative to Maximum Likelihood for estimating the parameters of IRT models for relatively large numbers of items in a genetic context. Additional benefits of the IRT approach are discussed including the estimation of latent trait scores, including genetic factor scores, and their sampling errors.

Adolescent↗

Immediate antecedents of cigarette smoking in smokers with and without posttraumatic stress disorder: a preliminary study.

Using ambulatory methods for 1 day of monitoring, the authors of this study investigated the association between smoking and situational cues in 63 smokers with posttraumatic stress disorder (PTSD) and 32 smokers without PTSD. Generalized estimating equations contrasted 682 smoking and 444 nonsmoking situations by group status. Smoking was strongly related to craving, positive and negative affect, PTSD symptoms, restlessness, and several situational variables among PTSD smokers. For non-PTSD smokers, the only significant antecedent variables for smoking were craving, drinking coffee, being alone, not being with family, not working, and being around others who were smoking. These results are consistent with previous ambulatory findings regarding mood in smokers but also underscore that, in certain populations, mood and symptom variables may be significantly associated with ad lib smoking.

Adult↗

Genetic and environmental influences on the relative timing of pubertal change.

A multicategory item-response theory model was developed to characterize developmental changes in three items relating to the assessment of puberty in adolescent twin girls and boys. The model allowed for the fixed effects of age on probability of endorsing the responses and for the random effects of individual differences on the timing of pubertal changes relative to chronological age. In girls, the model was applied three-wave data on twin pairs (N = 414 female monozygotic [MZ] and 197 female dizygotic [DZ] pairs) and female twins from boy-girl pairs (N = 300 twins) from the Virginia Twin Study of Adolescent Behavioral Development. In boys, the data comprised 318 MZ and 185 DZ pairs and 297 male twins from boy-girl pairs. A total of 3172 and 2790 individual twin assessments were available in girls and boys, respectively, spanning ages 8-17 years. The availability of twin data allows the contributions of genes, the shared environment and individual unique environmental experiences to be resolved in the relative timing of pubertal changes. Parameters of the mixed model including fixed effects of age and random effects of genes and environment were estimated by Markov Chain Monte Carlo simulations using the BUGS algorithm for Gibbs sampling. The estimated standard deviation of random differences in the timing of puberty relative to age was 0.96 years in girls and 1.01 years in boys. The estimated intraclass correlations for the relative timing of pubertal changes were 0.99 +/-0.01 in MZ girls, 0.52 +/-0.02 in DZ girls, 0.88 +/-0.04 in MZ boys and 0.44+/-0.02 in DZ boys, indicating a very large contribution of genetic factors to the relative timing of pubertal change in both sexes. Additive genetic factors account for an estimated 96.3+/-3.3% of the total variance in random effects in girls and 88.0+/-3.6% in boys. Shared environmental influences account for 3.6+/-3.4% in girls and 0% in boys. In girls, nonshared environmental effects explain 0.1+/-0.1% of the total residual variance. The comparable figure in boys is 12.0+/-3.6%.

Adolescent↗

Prevalence and development of psychiatric disorders in childhood and adolescence.

BACKGROUND: This longitudinal community study assessed the prevalence and development of psychiatric disorders from age 9 through 16 years and examined homotypic and heterotypic continuity. METHODS: A representative population sample of 1420 children aged 9 to 13 years at intake were assessed annually for DSM-IV disorders until age 16 years. RESULTS: Although 3-month prevalence of any disorder averaged 13.3% (95% confidence interval [CI], 11.7%-15.0%), during the study period 36.7% of participants (31% of girls and 42% of boys) had at least 1 psychiatric disorder. Some disorders (social anxiety, panic, depression, and substance abuse) increased in prevalence, whereas others, including separation anxiety disorder and attention-deficit/hyperactivity disorder (ADHD), decreased. Lagged analyses showed that children with a history of psychiatric disorder were 3 times more likely than those with no previous disorder to have a diagnosis at any subsequent wave (odds ratio, 3.7; 95% CI, 2.9-4.9; P<.001). Risk from a previous diagnosis was high among both girls and boys, but it was significantly higher among girls. Continuity of the same disorder (homotypic) was significant for all disorders except specific phobias. Continuity from one diagnosis to another (heterotypic) was significant from depression to anxiety and anxiety to depression, from ADHD to oppositional defiant disorder, and from anxiety and conduct disorder to substance abuse. Almost all the heterotypic continuity was seen in girls. CONCLUSIONS: The risk of having at least 1 psychiatric disorder by age 16 years is much higher than point estimates would suggest. Concurrent comorbidity and homotypic and heterotypic continuity are more marked in girls than in boys.

Adolescent↗

Markov Chain Monte Carlo approaches to analysis of genetic and environmental components of human developmental change and G x E interaction.

The linear structural model has provided the statistical backbone of the analysis of twin and family data for 25 years. A new generation of questions cannot easily be forced into the framework of current approaches to modeling and data analysis because they involve nonlinear processes. Maximizing the likelihood with respect to parameters of such nonlinear models is often cumbersome and does not yield easily to current numerical methods. The application of Markov Chain Monte Carlo (MCMC) methods to modeling the nonlinear effects of genes and environment in MZ and DZ twins is outlined. Nonlinear developmental change and genotype x environment interaction in the presence of genotype-environment correlation are explored in simulated twin data. The MCMC method recovers the simulated parameters and provides estimates of error and latent (missing) trait values. Possible limitations of MCMC methods are discussed. Further studies are necessary explore the value of an approach that could extend the horizons of research in developmental genetic epidemiology.

Child↗

Resolving multiple epigenetic pathways to adolescent depression.

BACKGROUND: Genotype x environment interaction (G x E) arises when genes influence sensitivity to the environment. G x E is easily recognized in experimental organisms that permit randomization of genotypes over fixed environmental treatments. Genotype-environment correlation (rGE) arises when genetic effects create or evoke exposure to environmental differences. Simultaneous analysis of G x E and such 'active' or 'evocative' rGE in humans is intractable with linear structural models widely used in behavioral genetics because environments are random effects often correlated with genotype. The causes of the environmental variation, therefore, need to be modeled at the same time as the primary outcome. METHODS: A Markov Chain Monte Carlo approach is used to resolve three distinct pathways involving genes and life events affecting the development of post-pubertal depression in female twins and its relationship to pre-pubertal anxiety: 1) the main of genes and environment; 2) the interaction of genes and environment (G x E); and 3) genotype-environment correlation (rGE). RESULTS: A model including G x E and rGE in addition to the main effects of genes and environment yields significant estimates of the parameters reflecting G x E and rGE. Omission of either G x E or rGE leads to overestimation of the effects of the measured environment and the unique random environment within families. CONCLUSIONS: 1) Genetic differences in anxiety create later genetic differences in depression; 2) genes that affect early anxiety increase sensitivity (G x E) to adverse life events; 3) genes that increase risk to early anxiety increase exposure to depressogenic environmental influences (rGE). Additional genetic effects, specific to depression, further increase sensitivity to adversity. Failure to take into account the effects of G x E and rGE will lead to misunderstanding how genes and environment affect complex behavior.

Adolescent↗

Obesity and psychiatric disorder: developmental trajectories.

OBJECTIVES: To identify age-related trajectories of obesity from childhood into adolescence, and to test the association of these trajectories with the development of psychiatric disorders (conduct disorder, oppositional defiant disorder, attention-deficit/hyperactivity disorder, substance abuse, depression, and anxiety). METHODS: White children (N = 991) 9 to 16 years old from the Great Smoky Mountains Study, a representative sample of rural youth, were evaluated annually over an 8-year period for height, weight, psychiatric disorder, and vulnerabilities for psychiatric disorder. Longitudinal analyses on the repeated measures data were conducted using developmental trajectory models and generalized estimating equation models. RESULTS: Obesity was 3 to 4 times more common than expected from national rates using Centers for Disease Control and Prevention 2000 criteria. Four developmental trajectories of obesity were found: no obesity (73%), chronic obesity (15%), childhood obesity (5%), and adolescent obesity (7%). Only chronic obesity was associated with psychiatric disorder: oppositional defiant disorder in boys and girls and depressive disorders in boys. CONCLUSIONS: In a general population sample studied longitudinally, chronic obesity was associated with psychopathology.

Adolescent↗

Psychiatric disorder, impairment, and service use in rural African American and white youth.

BACKGROUND: The Caring for Children in the Community Study examined the prevalence of DSM-IV psychiatric disorders and correlates of mental health service use in rural African American and white youth. METHODS: Four thousand five hundred youth aged 9 to 17 years from 4 North Carolina counties were randomly selected from school databases. Parents completed telephone questionnaires about their children's behavior problems. A second-stage sample of 1302 was identified for recruitment into the interview phase of the study, and 920 (70.7%) of these were successfully interviewed at home using the Child and Adolescent Psychiatric Assessment and related measures of service use. RESULTS: Weighted back to general population estimates, 21.1% of youth had 1 or more DSM-IV psychiatric disorders in the past 3 months. Prevalence was similar in African American (20.5%) and white (21.9%) youth. The only ethnic difference was an excess of depressive disorders in white youth (4.6% vs 1.4%). Thirteen percent of participants (36.0% of those with a diagnosis) received mental health care in the past 3 months. White youth were more likely than African American youth to use specialty mental health services (6.1% vs 3.2%), but services provided by schools showed very little ethnic disparity (8.6% vs 9.2%). The effect of children's symptoms on their parents was the strongest correlate of specialty mental health care. CONCLUSIONS: In this rural sample, African American and white youth were equally likely to have psychiatric disorders, but African Americans were less likely to use specialty mental health services. School services provided care to the largest number of youths of both ethnic groups.

Adolescent↗

The prevalence of potentially traumatic events in childhood and adolescence.

This paper examines exposure to potentially traumatic events from middle childhood through adolescence, and vulnerability to such exposure. Analyses are based on the first 4 annual waves of data from a longitudinal general population study of youth in western North Carolina, involving 4,965 interviews with 1,420 children and adolescents and their parents or guardians. Participants reported on DSM extreme stressors ("high magnitude events"), other potentially traumatic events ("low magnitude events"), and background vulnerability factors. In this general population sample, one-quarter experienced at least one high magnitude event by age 16, 6% within the past 3 months. One third experienced a low magnitude event in the past 3 months. The likelihood of such exposure increased with the number of vulnerability factors.

Adolescent↗

Depression scale scores in 8-17-year-olds: effects of age and gender.

BACKGROUND: The excess of unipolar depression in females emerges in adolescence. However, studies of age effects on depression scale scores have produced divergent estimates of changes from childhood to adolescence. METHOD: We explored possible reasons for this discrepancy in two large, longitudinal samples of twins and singletons aged 8-17. RESULTS: There were no differences between twins and singletons in their scores on the Short Mood and Feelings Questionnaire (SMFQ), a 13-item self-report depression scale. SMFQ scores for boys fell over this age-range, while those for girls fell from age 9 to age 11 and then increased from age 12 to age 17. The mean scores of girls under 12 and those 12 and over differed by only around one-fifth of a standard deviation. However, given the non-normal distribution of the scores, a cut point that selected the upper 6% of scores created the expected female:male ratio of 2:1. CONCLUSIONS: Implications for future research on adolescent depression are discussed.

Adolescent↗