Common genetic risk variants have been implicated in the etiology of clinical attention-deficit/hyperactivity disorder (ADHD) diagnoses and symptoms in the general population. However, given the ...extensive comorbidity across ADHD and other psychiatric conditions, the extent to which genetic variants associated with ADHD also influence broader psychopathology dimensions remains unclear. The aim of this study was to evaluate the associations between ADHD polygenic risk scores (PRS) and a broad range of childhood psychiatric symptoms, and to quantify the extent to which such associations can be attributed to a general factor of childhood psychopathology. We derived ADHD PRS for 13,457 children aged 9 or 12 from the Child and Adolescent Twin Study in Sweden, using results from an independent meta-analysis of genome-wide association studies of ADHD diagnosis and symptoms. We estimated associations between ADHD PRS, a general psychopathology factor, and several dimensions of neurodevelopmental, externalizing, and internalizing symptoms, using structural equation modeling. Higher ADHD PRS were statistically significantly associated with elevated neurodevelopmental, externalizing, and depressive symptoms (R
= 0.26-1.69%), but not with anxiety. After accounting for a general psychopathology factor, on which all symptoms loaded positively (mean loading = 0.50, range = 0.09-0.91), an association with specific hyperactivity/impulsivity remained significant. ADHD PRS explained ~ 1% (p value < 0.0001) of the variance in the general psychopathology factor and ~ 0.50% (p value < 0.0001) in specific hyperactivity/impulsivity. Our results suggest that common genetic risk variants associated with ADHD, and captured by PRS, also influence a general genetic liability towards broad childhood psychopathology in the general population, in addition to a specific association with hyperactivity/impulsivity symptoms.
Attitudes to COVID-19 vaccination vary considerably within and between countries. Although the contribution of socio-demographic factors to these attitudes has been studied, the role of social media ...and how it interacts with news about vaccine development and efficacy is uncertain. We examined around 2 million tweets from 522,893 persons in the UK from November 2020 to January 2021 to evaluate links between Twitter content about vaccines and major scientific news announcements about vaccines. The proportion of tweets with negative vaccine content varied, with reductions of 20-24% on the same day as major news announcement. However, the proportion of negative tweets reverted back to an average of around 40% within a few days. Engagement rates were higher for negative tweets. Public health messaging could consider the dynamics of Twitter-related traffic and the potential contribution of more targeted social media campaigns to address vaccine hesitancy.
Growing evidence suggests that ADHD, an early onset neurodevelopmental disorder, is associated with poor somatic health in adulthood. However, the mechanisms underlying these associations are poorly ...understood. Here, we tested whether ADHD polygenic risk scores (PRS) are associated with mid-to-late life somatic health in a general population sample. Furthermore, we explored whether potential associations were moderated and mediated by life-course risk factors. We derived ADHD-PRS in 10,645 Swedish twins born between 1911 and 1958. Sixteen cardiometabolic, autoimmune/inflammatory, and neurological health conditions were evaluated using self-report (age range at measure 42-88 years) and clinical diagnoses defined by International Classification of Diseases codes in national registers. We estimated associations of ADHD-PRS with somatic outcomes using generalized estimating equations, and tested moderation and mediation of these associations by four life-course risk factors (education level, body mass index BMI, tobacco use, alcohol misuse). Results showed that higher ADHD-PRS were associated with increased risk of seven somatic outcomes (heart failure, cerebro- and peripheral vascular disease, obesity, type 1 diabetes, rheumatoid arthritis, and migraine) with odds ratios ranging 1.07 to 1.20. We observed significant mediation effects by education, BMI, tobacco use, and alcohol misuse, primarily for associations of ADHD-PRS with cardiometabolic outcomes. No moderation effects survived multiple testing correction. Our findings suggests that higher ADHD genetic liability confers a modest risk increase for several somatic health problems in mid-to-late life, particularly in the cardiometabolic domain. These associations were observable in the general population, even in the absence of medical treatment for ADHD, and appear to be in part mediated by life-course risk factors.
Background
Attention‐deficit/hyperactivity disorder (ADHD) aggregates in families. To date, the strength, pattern, and characteristics of the familial aggregation have not been thoroughly assessed in ...a population‐based family sample.
Methods
In this cohort study, we identified relative pairs of twins, full and half‐siblings, and full and half cousins from 1,656,943 unique individuals born in Sweden between 1985 and 2006. The relatives of index persons were followed from their third birthday to 31 December 2009 for ADHD diagnosis. Birth year adjusted hazard ratio (HR), that is, the rate of ADHD in relatives of ADHD‐affected index persons compared with the rate of ADHD in relatives of unaffected index persons, was estimated in the different types of relatives using Cox proportional hazards model.
Results
During the follow‐up, 31,865 individuals were diagnosed with ADHD (male to female ratio was 3.7). The birth year adjusted HRs were as follows: 70.45 for monozygotic twins; 8.44 for dizygotic twins; 8.27 for full siblings; 2.86 for maternal half‐siblings; 2.31 for paternal half‐siblings; 2.24 for full cousins; 1.47 for half cousins. Maternal half‐siblings had significantly higher HR than in paternal half‐siblings. The HR did not seem to be affected by index person's sex. Full siblings of index persons with ADHD diagnosis present at age 18 or older had a higher rate of ADHD (HR: 11.49) than full siblings of index persons with ADHD diagnosis only before age 18 (HR: 4.68).
Conclusions
Familial aggregation of ADHD increases with increasing genetic relatedness. The familial aggregation is driven by not only genetic factors but also a small amount of shared environmental factors. Persistence of ADHD into adulthood indexes stronger familial aggregation of ADHD.
Objective
Information on mental disorders over time is critical for documenting changes in population burden, and aiding understanding of potential causal and non‐causal factors. The aim of this ...study was to provide temporal changes in the sex‐ and age‐specific incidence rates (IR) of mental disorders diagnosed in Danish hospitals during five decades and investigate whether such changes may be attributable to changes in administrative reporting practice.
Methods
This population‐based cohort study included all people living in Denmark between 1970 and 2016. Mental disorders diagnoses were obtained from the Danish Psychiatric Central Research Register. We estimated the IR of each mental disorder (all persons, and sex‐ and age‐specific IRs) and examined the impact of two administrative changes.
Results
Our study included 9 107 157 people, followed for 233.0 million person‐years. During follow‐up, 9.5% were diagnosed with at least one mental disorder. The IR for any mental disorder was 39.0 per 10,000 person‐years. Despite fluctuations, this increased between 1970–84 and 2005–2016, from 28.9 to 63.0 per 10,000 person‐years. Increases were most pronounced for younger age groups. Administrative changes did appear to influence incidence rates.
Conclusion
Mental disorder IRs have increased in Denmark since 1970, with age of diagnosis shifting downwards. Both trends were likely impacted by administrative changes, while the latter is likely to be (partly) attributable to earlier detection and increased reporting of child‐onset conditions. Our findings may provide valuable context of the epidemiology of mental disorders across age groups for comparison with other studies and populations.
There is scarcity of research investigating the validity of self-report of attention deficit hyperactivity disorder (ADHD) symptoms compared to other informants, such as parents. This study aimed to ...compare the predictive associations of ADHD symptoms rated by parents and their children across adolescence on a range of adverse socioeconomic and health outcomes in early adulthood. Parent- and self-rated ADHD symptoms were assessed in 2960 individuals in early (13–14 years) and late adolescence (16–17 years). Logistic regression analyses were used to compare the associations between parent- and self-rated ADHD symptoms at both time points and adverse life outcomes in young adulthood obtained from Swedish national registries. Both parent- and self-ratings of ADHD symptoms were associated with increased risk for adverse outcomes, although associations of parent-ratings were more often statistically significant and were generally stronger (OR = 1.12–1.49,
p
< 0.05) than self-ratings (OR = 1.07–1.17,
p
< 0.05). After controlling for the other informant, parent-ratings of ADHD symptoms in both early and late adolescence significantly predicted academic and occupational failure, criminal convictions and traffic-related injuries, while self-ratings of ADHD symptoms only in late adolescence predicted substance use disorder and academic failure. Our findings suggest that both parent- and self-ratings of ADHD symptoms in adolescence provides valuable information on risk of future adverse socioeconomic and health outcomes, however, self-ratings are not valuable once parent-ratings have been taken into account in predicting most outcomes. Thus, clinicians and researchers should prioritize parent-ratings over self-ratings.
Attention-deficit/hyperactivity disorder (ADHD) has been linked to immaturity relative to peers in childhood, yet it is unclear how such immaturity is associated with ADHD across development. This ...longitudinal twin study examined the genetic and environmental contributions to the association between parents' perception of their child's immaturity relative to peers (RI) in childhood and ADHD symptoms across development.
1,302 twin pairs from the Swedish Twin Study of Child and Adolescent Development were followed prospectively from childhood to early adulthood. Parent ratings of RI were collected at 8 to 9 years and parent and self-ratings of ADHD symptoms were collected at 8 to 9, 13 to 14, 16 to 17, and 19 to 20 years using the Child Behavior Checklist Attention Problems scale. In addition, ADHD symptoms corresponding to DSM criteria were used for sensitivity analysis. Analyses were conducted using longitudinal structural equation modeling with multiple raters.
RI-related etiologic factors, predominantly influenced by genes, explained 10-14% of the variance in ADHD symptoms from 8 to 9 up to 16 to 17 years. The influence of these RI-related factors on ADHD symptoms attenuated to 4% by 19 to 20 years of age. The remaining variance in ADHD symptoms was primarily explained by genetic factors independent of RI, which remained relatively stable across development, explaining 19% to 30% of the variance in ADHD symptoms from 13 to 14 up to 19 to 20 years.
The results show that RI is significantly associated with ADHD symptoms, particularly during childhood and adolescence, and that the association is primarily explained by a shared genetic liability. Nevertheless, the magnitude of associations across development was modest, highlighting that RI is merely one aspect contributing to the complex etiology of ADHD symptoms.
Abstract
Attention‐deficit/hyperactivity disorder (ADHD) often co‐occurs with other psychiatric and physical diseases. However, available evidence on associations between ADHD and cardiovascular ...diseases (CVDs) is mixed. To systematically review, quantitatively synthesize, and appraise available evidence on the link between ADHD with CVDs, we searched relevant articles in PubMed, Embase, PsycINFO, and Web of Science from inception to May 1, 2022. Study quality was assessed by using the Newcastle‐Ottawa Scale, and random‐effects model meta‐analyses were performed. A total of 18,391,169 (ADHD:
n
= 421,224) individuals from 11 studies were included in our systematic review and 8,196,648 (ADHD = 332,619) individuals from five studies were included in the main meta‐analysis of adjusted estimates. Pooled estimates showed that ADHD was significantly associated with an increased risk of CVDs in analyses based on adjusted effect size (odds ratio (OR) = 1.96; 95% confidence interval (CI) = 1.19–2.23,
Q
= 140.74,
P
Q
< 0.001,
I
2
= 97.2%). When restricted among adults, the heterogeneity declined to null (OR = 1.73; 95% CI = 1.14–2.62,
Q
= 6.28,
P
Q
= 0.10,
I
2
= 6.28%), suggesting age might be the main source of heterogeneity. In subgroup analyses, we found increased risk of CVDs associated with ADHD across age groups, type of CVDs, and data sources. This systematic review and meta‐analyses indicate that ADHD is associated with increased risk for CVDs, but further studies with various study designs are warranted to advance the understanding of the underlying mechanisms for the observed association between ADHD and CVDs. Additional research is also needed to resolve the role of ADHD medications which remains unclear due to the limited number of primary studies exploring this issue.