Chapter 14: Psychoneuroimmunology and Immune-Related Disorders

The foundation establishes that the body employs both innate immunity through rapid responses by phagocytes and natural killer cells, and adaptive immunity through more targeted B and T lymphocyte responses. Psychological stress significantly affects immune competence through different pathways depending on stressor duration: acute stressors enhance natural immunity in preparation for immediate threats while suppressing specific immunity, whereas chronic stressors impair both cellular and humoral immunity and promote persistent inflammatory states that increase disease vulnerability. Negative emotional states, particularly depression, and interpersonal stressors such as marital discord, social isolation, and loss substantially compromise immune functioning. Protective factors including optimism, perceived control, social support, and meaning-making can buffer stress effects on immunity, and psychological interventions including relaxation, mindfulness, and expressive writing demonstrably enhance immune markers. The chapter then explores how these psychoneuroimmunological principles apply to specific diseases: HIV infection and AIDS, where psychological factors influence treatment adherence and disease progression through effects on helper T cells; cancer, where stress-induced neuroendocrine dysregulation impairs natural killer cell function and disease management success depends partly on coping strategies and social support; autoimmune arthritis disorders, where emotional stress exacerbates joint inflammation and pain; and Type I diabetes, where developmental challenges and treatment complexity create substantial adherence obstacles in adolescents. Throughout these disease contexts, evidence demonstrates that cognitive-behavioral interventions, stress management techniques, and psychological support meaningfully improve both disease outcomes and quality of life by modulating the interconnected systems that regulate immune responses.