Can adaptive hyperactivation result in a positive score on the Mood Disorder Questionnaire? Evidence from a case-control study over a community survey.

Background: Bipolar Disorder (BD) remains challenging to identify, and the Mood Disorder Questionnaire (MDQ) may capture heterogeneous forms of hyperactivation, including adaptive patterns unrelated to psychopathology. Objectives: To determine whether MDQ-positive individuals include a subgroup with adaptive hyperactivation-characterized by high quality of life (QoL) and minimal psychiatric morbidity-and to examine whether MDQ positivity also identifies diagnoses beyond BD. Methods: Using data from a large Italian community survey with DSM-IV clinical interviews and MDQ screening, we conducted a case-control analysis. MDQ-positive individuals were stratified by SF-12 QoL scores (>40 vs. ≤40), and matched MDQ-negative controls were selected by age and sex. Psychiatric diagnoses were compared using ANOVA and chi-square tests. Results: Among 91 MDQ-positive participants, 33% showed high QoL and exhibited markedly fewer psychiatric diagnoses than those with low QoL (χ²=15.529, p<0.0001). High-QoL MDQ-positive individuals displayed psychiatric morbidity comparable to MDQ-negative controls, whereas low-QoL MDQ-positive individuals showed excess anxiety, obsessive-compulsive, and eating disorders. Conclusions: MDQ positivity identifies a heterogeneous population, including individuals with adaptive hyperactivation and preserved functioning. These findings highlight the need for more refined instruments capable of distinguishing adaptive from pathological hyperactivation and caution against over-pathologizing MDQ positivity in clinical and public health settings.