Chapter 14: Depressive Disorders – Causes & Care

Key conditions discussed include Major Depressive Disorder (MDD), defined by a persistently depressed mood or loss of interest lasting at least two weeks, as well as Persistent Depressive Disorder (formerly dysthymia), Premenstrual Dysphoric Disorder (PMDD), and Disruptive Mood Dysregulation Disorder (DMDD), a diagnosis introduced for children with severe irritability previously mislabeled as bipolar disorder. Epidemiologically, depression is a leading global cause of disability, frequently affecting young adults and women, and often coexisting with anxiety or substance use problems. Etiology is viewed through the complex Diathesis-Stress Model, where genetic and biological vulnerabilities interact with life stressors. Biological factors encompass abnormalities in key neurotransmitters like serotonin and norepinephrine, along with hyperactivity in the hypothalamic-pituitary-adrenal (HPA) axis and a growing understanding of the role of inflammation. Cognitive theory highlights how automatic negative thought patterns, such as Beck's cognitive triad (negative views of self, the world, and the future), perpetuate depressive feelings. The nursing process prioritizes ongoing assessment for suicidal ideation, evaluating changes in physical function (vegetative signs), and utilizing tools like the Patient Health Questionnaire-9 (PHQ-9). Treatment follows a three-phase plan (acute, continuation, maintenance), commonly employing psychopharmacology—Selective Serotonin Reuptake Inhibitors (SSRIs) are first-line, but specialized medications like esketamine (for treatment-resistant depression) and brexanolone (for postpartum depression) are available. Somatic treatments, including highly effective Electroconvulsive Therapy (ECT), Repetitive Transcranial Magnetic Stimulation (rTMS), and Vagus Nerve Stimulation (VNS), provide alternatives, while therapeutic modalities like Cognitive Behavioral Therapy (CBT) and Interpersonal Therapy (IPT) remain essential for long-term recovery and managing cognitive distortions.