Is irritability multidimensional: Psychometrics of The Irritability and Dysregulation of Emotion Scale (TIDES-13).

Irritability is a common, impairing, and potentially multifaceted manifestation of psychopathology. We designed The Irritability and Dysregulation of Emotion Scale (TIDES-13) to determine whether various expressions of irritability in children and youth form multiple subdimensions with distinct correlates. We administered parent-report (n = 3875, mean age = 8.9) and youth self-report (n = 579, mean age = 15.1) versions of TIDES-13 in a population and community-based sample. We conducted exploratory/confirmatory factor analyses and regression analyses to examine the dimensionality of TIDES-13 and the associations of the scale with age, gender, anxiety, depression, ODD, ADHD traits, and the Affective Reactivity Index (ARI). A higher-order model with a global irritability dimension and four subdimensions, including proneness to anger (PA), internalized negative emotional reactivity (iNER), externalized negative emotional reactivity (eNER), and reactive aggression (RA), showed good to excellent fit in both parent-report and self-report. The global irritability dimension showed excellent internal reliability (⍵Total; parent-report = 0.97, ⍵Total; self-report = 0.95), explained a majority of the item variance (⍵Hierarchical; parent-report = 0.94, ⍵Hierarchical; self-report = 0.90), and was moderately correlated with the ARI (rparent = 0.68, rself = 0.77). Subdimensions PA, eNER, and RA were negatively associated with age in males, whereas iNER was positively associated with age in females. Traits of ODD and ADHD were associated primarily with the global irritability dimension, whereas iNER was strongly associated with anxiety and depression traits over and above the global irritability dimension. Our results support a unidimensional interpretation of irritability in a population sample. However, limited evidence of specific behavioral, age, and sex correlates with particular irritability subdimensions may warrant further investigation.

Sex Modifies the Associations of APOEɛ4 with Neuropsychiatric Symptom Burden in Both At-Risk and Clinical Cohorts of Alzheimer's Disease.

BACKGROUND: Recent work suggests that APOEɛ4/4 females with Alzheimer's disease (AD) are more susceptible to developing neuropsychiatric symptoms (NPS). OBJECTIVE: To examine the interaction of sex and APOEɛ4 status on NPS burden using two independent cohorts: 1) patients at risk for AD with mild cognitive impairment and/or major depressive disorder (n = 252) and 2) patients with probable AD (n = 7,261). METHODS: Regression models examined the interactive effects of sex and APOEɛ4 on the number of NPS experienced and NPS Severity. APOEɛ3/4 and APOEɛ4/4 were pooled in the at-risk cohort due to the sample size. RESULTS: In the at-risk cohort, there was a significant sex*APOEɛ4 interaction (p = 0.007) such that the association of APOEɛ4 with NPS was greater in females than in males (incident rate ratio (IRR) = 2.0). APOEɛ4/4 females had the most NPS (mean = 1.9) and the highest severity scores (mean = 3.5) of any subgroup. In the clinical cohort, APOEɛ4/4 females had significantly more NPS (IRR = 1.1, p = 0.001, mean = 3.1) and higher severity scores (b = 0.31, p = 0.015, mean = 3.7) than APOEɛ3/3 females (meanNPS = 2.9, meanSeverity = 3.3). No association was found in males. CONCLUSION: Our study suggests that sex modifies the association of APOEɛ4 on NPS burden. APOEɛ4/4 females may be particularly susceptible to increased NPS burden among individuals with AD and among individuals at risk for AD. Further investigation into the mechanisms behind these associations are needed.