Background. Panic disorder often has a chronic course and is comorbid with depression. Many different psychological factors may have impact on both chronicity and comorbidity. Aim. The purpose of the study was to access the prevalence of depression among panic patients. Defence style, sense of coherence and family functioning of patients were analysed in a link with anxiety and depressive symptoms. Methods. The author examined 75 patients suffering from severe PD. Mini International Neuropsychiatric Interview, Polish version 5.0.0, Panic and Agoraphobia Scale, Beck's Depression Inventory, Family Functioning Questionnaire (KOR), Sense of Coherence Scale (SOC-29), Defence Style Questionnaire (DSQ-40) and Life Inventory were used. Results. The study revealed that depressive symptoms are often comorbid with PD, but only 17.3% of the group suffered from severe depression. Duration of PD was linked with many psychological factors. Anxiety and depressive symptoms were linked with catastrophic interpretation of bodily sensations, coherence and defence mechanisms, but not with family functioning. Conclusion. It is possible that psychological problems affect duration and severity of PD.