Anxiety disorders: a cross-sectional study of clinical and biological associations

It is estimated that more than 300 million people worldwide suffer from anxiety disorders. Oxidative stress is increasingly recognized as a factor in the development and progression of anxiety disorders. This study aimed to investigate the association of psychological symptoms and oxidative stress parameters with anxiety disorders. This is a cross-sectional study that included a paired sample of adults diagnosed with anxiety disorders (116 individuals) and without a diagnosis of anxiety disorders (234 individuals). Data collection took place from September 2020 to July 2021 during the COVID-19 pandemic. We assessed the presence of psychiatric conditions using standardized diagnostic criteria, the Hamilton Rating Scale for Anxiety (HAM-A), the Hamilton Rating Scale for Depression (HAM-D), the Biological Rhythms in Neuropsychiatry Assessment Interview (BRIAN), and the Functional Assessment Short Test (FAST). Stress levels were assessed using the Stress Symptom Inventory. Oxidative stress parameters were measured in the serum sample. Individuals with anxiety disorders had higher levels of stress, greater severity of depressive and anxiety symptoms, impaired cognitive functioning, and greater impairment in biological rhythms compared with individuals without anxiety disorders. In addition, individuals with anxiety disorders had decreased total antioxidant capacity compared with individuals without anxiety disorders. However, after correcting for multiple testing, the oxidative status did not differ between groups. This study demonstrates that anxiety disorders are associated not only with increased psychological distress and functional impairment but also with biological alterations. These findings support an exploratory role of oxidative stress in the pathophysiology of anxiety disorders.