Occupational performance characteristics in patients with attention‐deficit/hyperactivity disorder comorbid with major depressive disorders: Discriminant analysis with major depressive disorders

Aim Assessing symptoms and daily functioning in individuals with attention‐deficit/hyperactivity disorder (ADHD) comorbid with major depressive disorder (MDD) is challenging because of their limited self‐monitoring abilities. This study aimed to determine whether specific occupational behaviors could differentiate patients with ADHD comorbid with MDD from those with MDD alone. Methods This study included patients who underwent a comprehensive assessment for suspected difficult‐to‐treat depression at Kyorin University Hospital, Japan. During an artistic activity program, three therapists evaluated occupational performance characteristics to identify potential traits. Characteristics in patients with comorbid ADHD and MDD were compared to those in MDD alone using the chi‐square test. Key discriminators were selected based on significant characteristics ( p < 0.01). Discriminant analysis was conducted to enhance group differentiation, with prediction accuracy assessed via area under the curve (AUC). This study was approved by the Research Ethics Committee. Results A total of 71 occupational performance characteristics were identified through retrospective analysis, of which 12 showed significant differences between 29 patients with comorbid ADHD and MDD and 35 patients with MDD alone. Four variables were selected as independent predictors in the discriminant analysis: “Have its own manners,” “Feel uncomfortable in groups,” “Work only at your own pace,” and “Ask questions and consult.” These variables contributed to the construction of a linear discriminant function. The discriminant model yielded a Wilks' λ of 0.631 ( p < 0.001) and achieved a classification accuracy of 81.3%. The receiver operating characteristic (ROC) curve showed an AUC of 0.857, with a sensitivity of 72.4% and a specificity of 88.6%. Conclusion These findings highlight the role of occupational performance characteristics in differentiating comorbid ADHD and MDD from MDD alone. This approach may contribute to more tailored treatment strategies.