Genome-wide analysis of emotional lability in adult attention deficit hyperactivity disorder (ADHD)

The shared genetic basis of mood instability and psychiatric disorders: A cross-trait genome-wide association analysis

Recent genome-wide association studies of mood instability (MOOD) have found significant positive genetic correlation with major depression (DEP) and weak correlations with other psychiatric disorders. We investigated the polygenic overlap between MOOD and psychiatric disorders beyond genetic correlation to better characterize putative shared genetic determinants. GWAS summary statistics for schizophrenia (SCZ, n = 105,318), bipolar disorder (BIP, n = 413,466), DEP (n = 450,619), attention-deficit hyperactivity disorder (ADHD, n = 53,293), and MOOD (n = 363,705) were analyzed using the bivariate causal mixture model and conjunctional false discovery rate methods. MOOD correlated positively with all psychiatric disorders, but with wide variation in strength (r_g  = 0.10-0.62). Of 10.4 K genomic variants influencing MOOD, 4 K-9.4 K influenced psychiatric disorders. Furthermore, MOOD was jointly associated with DEP at 163 loci, SCZ at 110, BIP at 60 and ADHD at 25. Fifty-three jointly associated loci were overlapping across two or more disorders, seven of which had discordant effect directions on psychiatric disorders. Genes mapped to loci associated with MOOD and all four disorders were enriched in a single gene-set, "synapse organization." The extensive polygenic overlap indicates shared molecular underpinnings across MOOD and psychiatric disorders. However, distinct patterns of genetic correlation and effect directions may relate to differences in the core clinical features of each disorder.

Using ecological momentary assessment to enhance irritability phenotyping in a transdiagnostic sample of youth

Irritability is a transdiagnostic symptom dimension in developmental psychopathology, closely related to the Research Domain Criteria (RDoC) construct of frustrative nonreward. Consistent with the RDoC framework and calls for transdiagnostic, developmentally-sensitive assessment methods, we report data from a smartphone-based, naturalistic ecological momentary assessment (EMA) study of irritability. We assessed 109 children and adolescents (Mage = 12.55 years; 75.20% male) encompassing several diagnostic groups – disruptive mood dysregulation disorder (DMDD), attention-deficit/hyperactivity disorder (ADHD), anxiety disorders (ANX), healthy volunteers (HV). The participants rated symptoms three times per day for 1 week. Compliance with the EMA protocol was high. As tested using multilevel modeling, EMA ratings of irritability were strongly and consistently associated with in-clinic, gold-standard measures of irritability. Further, EMA ratings of irritability were significantly related to subjective frustration during a laboratory task eliciting frustrative nonreward. Irritability levels exhibited an expected graduated pattern across diagnostic groups, and the different EMA items measuring irritability were significantly associated with one another within all groups, supporting the transdiagnostic phenomenology of irritability. Additional analyses utilized EMA ratings of anxiety as a comparison with respect to convergent validity and transdiagnostic phenomenology. The results support new measurement tools that can be used in future studies of irritability and frustrative nonreward.

Alcohol and drug use disorders in adult attention-deficit/hyperactivity disorder: Prevalence and associations with attention-deficit/hyperactivity disorder symptom severity and emotional dysregulation

BACKGROUND

High risk of alcohol and drug use disorders in people with attention-deficit/hyperactivity disorder (ADHD) calls for exploratory research of relationships with clinical features of ADHD.

AIM

To estimate prevalence of alcohol/drug use disorders and associations with ADHD symptom severity and emotional dysregulation, in adults with ADHD.

METHODS

This observational cross-sectional clinical study consisted of patients admitted to a private psychiatric outpatient clinic in Oslo, Norway (2014-2018). Five-hundred and fifty-eight eligible patients diagnosed with ADHD (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria) agreed to participate. Alcohol and drug use disorders were diagnosed using the Mini International Neuropsychiatric Interview (MINI). Dependence and abuse were merged into “use” disorder as in MINI version 7.0/DSM-5. Questions were related both to lifetime and the past 12-mo. ADHD severity was assessed by the Adult ADHD Self Report Scale (ASRS). Subdivisions of the ASRS questionnaire as inattentive items and hyperactive/impulsivity items were recorded separately. Emotional dysregulation was assessed by the eight-item version of Barkley’s Current Behavior Scale - Self Report.

RESULTS

The 12-mo prevalence was 5.3% for alcohol use disorder and 13.7% for drug use disorder. The lifetime prevalence was 12.0% for alcohol use disorder and 27.7% for drug use disorder. Men had higher rates of both alcohol use disorder and drug use disorder compared to women. The prevalence of drug use disorder was more than twice that of alcohol use disorder for both sexes. The drugs most participants reported having used were (in descending order): Amphetamine (19.1%), cannabis (17.1%), cocaine or ecstasy (7.4%), benzodiazepines (7.4%), and heroin or other opioids (2.9%). Lifetime drug use disorder was significantly associated with both hyperactivity-impulsivity symptoms and emotional dysregulation symptom severity. Lifetime alcohol use disorder, on the other hand, was not significantly associated with ADHD symptoms or emotional dysregulation when adjusted for gender and age.

CONCLUSION

Patients with ADHD have a high lifetime prevalence of drug use disorder, which is associated with higher levels of hyperactivity-impulsivity symptoms and emotional dysregulation.

Evaluating chronic emotional dysregulation and irritability in relation to ADHD and depression genetic risk in children with ADHD

BACKGROUND

A central nosological problem concerns the etiological relationship of emotional dysregulation with ADHD. Molecular genetic risk scores provide a novel method for informing this question.

METHODS

Participants were 514 community-recruited children of Northern European descent age 7-11 defined as ADHD or non-ADHD by detailed research evaluation. Parents-rated ADHD on standardized ratings and child temperament on the Temperament in Middle Childhood Questionnaire (TMCQ) and reported on ADHD and comorbid disorders by semi-structured clinical interview. Categorical and dimensional variables were created for ADHD, emotional dysregulation (implicating disruption of regulation of both anger-irritability and of positive valence surgency-sensation seeking), and irritability alone (anger dysregulation). Genome-wide polygenic risk scores (PRS) were computed for ADHD and depression genetic liability. Structural equation models and computationally derived emotion profiles guided analysis.

RESULTS

The ADHD PRS was associated in variable-centered analyses with irritability (β = .179, 95% CI = 0.087-0.280; ΔR²  = .034, p < .0002), but also with surgency/sensation seeking (B = .146, 95%CI = 0.052-0.240, ΔR² =.022, p = .002). In person-centered analysis, the ADHD PRS was elevated in the emotion dysregulation ADHD group versus other ADHD children (OR = 1.44, 95% CI = 1.03-2.20, Nagelkerke ΔR²  = .013, p = .033) but did not differentiate irritable from surgent ADHD profiles. All effects were independent of variation in ADHD severity across traits or groups. The depression PRS was related to oppositional defiant disorder but not to ADHD emotion dysregulation.

CONCLUSIONS

Irritability-anger and surgency-sensation seeking, as forms of negative and positively valenced dysregulated affect in ADHD populations, both relate principally to ADHD genetic risk and not mood-related genetic risk.