Adults

Among the studies included in this review, twelve focused on the comorbidity of ADHD symptoms and negative affectivity. Many of them identified a high correlation between ADHD symptoms and anxiety (rated from 0.28, *p* < 0.008 to 0.42, *p* < 0.001) [9,120] and depressive symptoms (rated from 0.29, *p* < 0.001 to 0.38, *p* < 0.001) [9,120,132]. Both inattention and hyperactivity/impulsivity symptoms were correlated with anxiety (r = 0.68, *p* < 0.0001 and r = 0.57, *p* < 0.0001 respectively) and depressive symptoms (r = 0.56–0.63, *p* < 0.001 and r = 0.41–0.51, *p* < 0.001) [117,122]. As reported by several publications [109–111], Jacob and colleagues (2018) [108] showed that individuals who screened positive for adult ADHD (ASRS) had a greater risk for anxiety disorder (33.6% vs. 5.1%, *p* < 0.001), mood disorders such as major depressive disorder (17.1% vs. 2.1%, *p* < 0.001), as well as borderline personality disorder traits (24.0% vs. 2.7% *p* < 0.001). Gorlin and colleagues (2016) [110] did not find an association between ADHD diagnosis and higher anxiety and depressive disorders. However, that study was conducted with psychiatry outpatients who may have been under medication for mood and anxiety disorders.

ADHD symptomatology was also associated with a higher number of stressful life events (3 vs. 1.7 *p* < 0.001) and more frequent perceived stress (85.9% vs. 59.1%, *p* < 0.001) [108]. In addition, ED patients with ADHD symptoms had higher anxiety (*p* = 0.02) [124], higher perceived stress and lower life satisfaction and perceived social support than those with ADHD symptoms [134]. These results indicate high rates of negative affectivity for ADHD individuals. Both inattentive and hyperactivity-impulsivity symptoms were shown to be correlated negatively with effortful control-regulative temperament (inattention: r = −0.556, *p* < 0.001, hyperactivity: r = −0.348, *p* < 0.001 and impulsivity: r = −0.476, *p* < 0.001) [117], and positively with emotion regulation difficulties (r = 0.42, *p* < 0.001 for both inattentive and hyperactivity/impulsivity ADHD symptoms) [135].

3.3.2. Negative Affectivity and Disrupted Emotion Self-Regulation as Mediators in the Association between ADHD and Disordered Eating

#### Children and Adolescents

Tong and colleagues (2017) [126] clarified the association between ADHD symptoms and addictive-like eating behavior by introducing a potential mediating effect of depression in this relationship. Their data are in line with the hypothesis that ADHD is associated with bulimia and emotional overeating through depression. Koch and colleagues (2020) [137], who investigated the incidence of mental disorders in zero to three-year-old children, suggested that the associations between emotional and affective disorders and ED and ADHD respectively were stronger than the direct association between feeding and eating disorders and ADHD. Indeed, the comorbidity between feeding and eating disorders and ADHD was OR = 15.4 (95% CI 9.6–24.7), whereas the comorbidity between EAD (i.e., emotional and affective disorders) and feeding and eating disorders was OR = 66.8 (95% CI 42.6–104.7) and between EAD and ADHD was OR = 150.7 (95% CI 95.1–238.7). In a sample of overweight or obese children, Gowey and colleagues (2017) [112] found that negative affectivity mediated the relationship between ADHD symptoms and disordered eating. They found

significant interactions between body dissatisfaction and both inattentive and hyperactivity/impulsivity ADHD symptoms with an effect on addictive-like eating behavior, especially food preoccupation and oral control.
