Subthreshold and threshold attention deficit hyperactivity disorder symptoms in childhood: psychosocial outcomes in adolescence in boys and girls.

OBJECTIVE: To examine the association between different levels of childhood attention deficit hyperactivity disorder (ADHD) symptoms and sex differences in psychosocial outcomes during adolescence. METHOD: Swedish children (n = 4635) were screened for neuropsychiatric symptoms at age 9 or 12. ADHD symptoms were divided into three levels: screen-negative, screen-intermediate, and screen-positive. At follow-up (age 15), parents and teenagers filled out questionnaires regarding (i) hyperactivity/inattention, (ii) peer problems, (iii) school problems, (iv) internalizing problems, (v) antisocial behaviour, (vi) alcohol misuse, and (vii) drug misuse. All outcomes were controlled for symptoms of diagnostic categories other than ADHD. RESULTS: Increasing levels of ADHD symptoms in childhood were associated with higher proportions of adolescents who displayed negative psychosocial outcomes. More girls than boys reported internalizing problems (all levels) and risky drug use (screen-intermediate and screen-positive only). More boys reported antisocial behaviour at the screen-negative and screen-intermediate levels, but at the screen-positive level, similar proportions of girls and boys displayed antisocial behaviour. CONCLUSION: The findings support the view that ADHD symptoms, as well as their negative outcomes, are dimensionally distributed in the population and that adolescent girls and boys display different risk profiles. The findings confirm that ADHD symptoms are associated with higher risk of drug misuse in girls.

Language and mathematical problems as precursors of psychotic-like experiences and juvenile mania symptoms.

BACKGROUND: Psychotic-like experiences (PLEs) and juvenile mania in adolescence index risk for severe psychopathology in adulthood. The importance of childhood problems with communication, reading, speech and mathematics for the development of PLEs and juvenile mania is not well understood. METHOD: Through the Child and Adolescent Twin Study in Sweden, we identified 5812 children. The parents were interviewed about their children's development at age 9 or 12 years. At age 15 or 18 years, children and parents completed questionnaires targeting current PLEs and juvenile mania symptoms. Logistic regressions were used to assess associations between problems with communication, reading, speech and mathematics and PLEs/juvenile mania symptoms. To evaluate the relative importance of genes and environment in these associations, we used bivariate twin analyses based on structural equation models. RESULTS: Children with parent-endorsed childhood problems with communication, reading and mathematics had an increased risk of developing auditory hallucinations and parental-reported juvenile mania symptoms in adolescence. The most consistent finding was that children with childhood problems with communication, reading and mathematics had an increased risk of developing auditory hallucinations [for example, the risk for self-reported auditory hallucinations at age 15 was increased by 96% for children with communication problems: OR (odds ratio) 1.96, 95% confidence interval (CI) 1.33-2.88]. The twin analyses showed that genetic effects accounted for the increased risk of PLEs and juvenile mania symptoms among children with communication problems. CONCLUSIONS: Childhood problems with communication, reading and mathematics predict PLEs and juvenile mania symptoms in adolescence. Similar to the case for schizophrenia and bipolar disorder, PLEs and juvenile mania may share genetic aetiological factors.

A study of the possible association between adenosine A2A receptor gene polymorphisms and attention-deficit hyperactivity disorder traits.

The adenosine A2A receptor (ADORA2A) is linked to the dopamine neurotransmitter system and is also implicated in the regulation of alertness, suggesting a potential association with attention-deficit hyperactivity disorder (ADHD) traits. Furthermore, animal studies suggest that the ADORA2A may influence ADHD-like behavior. For that reason, the ADORA2A gene emerges as a promising candidate for studying the etiology of ADHD traits. The aim of this study was to examine the relationship between ADORA2A gene polymorphisms and ADHD traits in a large population-based sample. This study was based on the Child and Adolescent Twin Study in Sweden (CATSS), and included 1747 twins. Attention-deficit hyperactivity disorder traits were assessed through parental reports, and samples of DNA were collected. Associations between six single nucleotide polymorphisms (SNPs) and ADHD traits were examined, and results suggested a nominal association between ADHD traits and three of these SNPs: rs3761422, rs5751876 and rs35320474. For one of the SNPs, rs35320474, results remained significant after correction for multiple comparisons. These results indicate the possibility that the ADORA2A gene may be involved in ADHD traits. However, more studies replicating the present results are warranted before this association can be confirmed.

Autistic-like traits and their association with mental health problems in two nationwide twin cohorts of children and adults.

BACKGROUND: Autistic-like traits (ALTs), that is restrictions in intuitive social interaction, communication and flexibility of interests and behaviors, were studied in two population-based Swedish twin studies, one in children and one in adults: (1) to examine whether the variability in ALTs is a meaningful risk factor for concomitant attention deficit hyperactivity disorder (ADHD), anxiety, conduct problems, depression and substance abuse, and (2) to assess whether common genetic and environmental susceptibilities can help to explain co-existence of ALTs and traits associated with such concomitant problems. METHOD: Two nationwide twin cohorts from Sweden (consisting of 11 222 children and 18 349 adults) were assessed by DSM-based symptom algorithms for autism. The twins were divided into six groups based on their degree of ALTs and the risk for concomitant mental health problems was calculated for each group. Genetic and environmental susceptibilities common to ALTs and the other problem types were examined using bivariate twin modeling. RESULTS: In both cohorts, even the lowest degree of ALTs increased the risk for all other types of mental health problems, and these risk estimates increased monotonically with the number of ALTs. For all conditions, common genetic and environmental factors could be discerned. Overall, the phenotypic correlation between ALTs and the traits examined were less pronounced in adulthood than in childhood and less affected by genetic compared with environmental factors. CONCLUSIONS: Even low-grade ALTs are relevant to clinical psychiatry as they increase the risk for several heterotypical mental health problems. The association is influenced partly by common genetic and environmental susceptibilities. Attention to co-existing ALTs is warranted in research on a wide range of mental disorders.

Recent time trends in levels of self-reported anxiety, mental health service use and suicidal behaviour in Stockholm.

OBJECTIVE: To investigate recent time trends in several indicators of mental ill-health and the patterning of these indicators between genders and younger vs. older individuals in Stockholm County. METHOD: Several indicators were used; self-reported anxiety from the Swedish Survey of Living Conditions, information on psychiatric in-patient and out-patient care, attempted and completed suicides from national and regional registers. Gender- and age-specific trends were compared for the time period of 1997-2006. RESULTS: Self-reported anxiety and psychiatric service use increased among young individuals of both genders, while attempted suicides increased only among young women. By contrast, these indicators decreased or remained stable in the older age group from year 2001 and onwards. CONCLUSION: Our data indicate a rising, and highly prevalent, mental ill-health among the young in Stockholm County, a region representative of urbanized, secular Western societies.

Communication between courts and expert witnesses in legal proceedings concerning child sexual abuse in Sweden: a case review.

OBJECTIVE: The objective was to explore the communication between courts and expert witnesses in legal proceedings concerning child sexual abuse in Sweden. METHOD: A cross professional research team performed a qualitative text analysis of files covering 20 court cases (court report and expert witness statement) from 4 different years (1985, 1989, 1992, and 1997). RESULTS: Expert witnesses applied a wide variety of assessment procedures. Several patterns of communicative difficulties were identified, categorized as "mismatch," "misunderstanding," "misuse," and "missing pieces." Experts and courts sometimes used similar words (e.g., "credibility") but seemed to apply different meanings to them, indicating a lack of a mutual conceptual framework. CONCLUSIONS: The combination of brief expert assignments and diverse assessment procedures turned out to be a specific risk factor for communicative impairment. Alternate strategies for improved communication are discussed.