Theories of Illness: Biomedical and Biopsychosocial

• Theories of illness encompass models and frameworks explaining the nature, causes, and progression of diseases.
• These theories offer a basis for understanding health and disease, which impacts medical practices, public health strategies, and individual health behaviors.

Biomedical Model

• A dominant perspective in Western medicine.
• Illness is explained as a result of biological factors like pathogens, genetic mutations, or physiological malfunctions.
• Focuses on objective, quantifiable data such as lab results and physical symptoms.
• Psychological, social, and environmental factors affecting health are ignored.
• Treatment typically involves pharmaceutical interventions or surgery to address the biological cause of disease.
• The model is criticized for its reductionist approach.
• The patient's subjective experience and broader life context are often overlooked.

Biopsychosocial Model

• This is a more holistic approach considering the interplay of biological, psychological, and social factors in health and illness.
• Biological factors (e.g., genetics, physiology) interact with psychological factors (e.g., beliefs, emotions, behaviors) and social factors (e.g., socioeconomic status, cultural norms, social support) to influence health outcomes.
• The patient-provider relationship is important.
• A more comprehensive assessment and treatment plan is encouraged; one that addresses multiple dimensions of the patient's life.
• A more nuanced understanding of chronic illnesses, mental health disorders, and other complex conditions is provided.

Social-Ecological Model

• Expands beyond the individual to include broader community, organizational, and policy-level factors influencing health.
• Interconnectedness of various levels of influence is emphasized.
• Includes individual, interpersonal, organizational, community, and public policy levels.
• Useful for understanding and addressing health disparities.
• Interventions based on this model often target multiple levels for sustainable change.
• Highlights the role of social determinants of health, like poverty, education, and access to healthcare.

Germ Theory

• Many diseases are caused by microorganisms that invade the body.
• This theory is a cornerstone of modern medicine, leading to the development of antibiotics, vaccines, and improved sanitation practices.
• Before it, diseases were often attributed to miasmas or imbalances in the body's humors.
• Louis Pasteur and Robert Koch are key figures in its development.
• Koch's postulates offer a framework for establishing a causal relationship between a specific microbe and a disease.

Web of Causation

• Diseases have multiple interacting causes rather than a single linear cause.
• Illustrates the complex relationships among various factors.
• This includes genetic predispositions, environmental exposures, behavioral patterns, and social conditions.
• It is more suitable for understanding chronic diseases and helps in identifying potential intervention points.
• It is visualized as a web-like diagram with interconnected nodes representing different risk factors.

Epidemiological Triad

• Examines the relationships between agent, host, and environment in disease causation.
• The agent is the cause of the disease (e.g., bacteria, virus, toxin).
• The host is the organism affected by the disease.
• The environment includes external factors that influence exposure and susceptibility to the agent.
• Useful for understanding infectious diseases and designing prevention strategies.
• Changes in any of the components can affect the occurrence of disease.

Health Belief Model

• Explains and predicts health-related behaviors
• People's beliefs about their health problems, the perceived benefits and barriers to action, and self-efficacy explain engagement (or lack of engagement) in health-promoting behavior.
• Key constructs include perceived susceptibility, perceived severity, perceived benefits, perceived barriers, cues to action, and self-efficacy.
• Perceived susceptibility is the belief about the likelihood of getting a disease.
• Perceived severity is the belief about the seriousness of the disease and its consequences.
• Perceived benefits are the belief about the effectiveness of taking action to reduce the risk or severity of the disease.
• Perceived barriers are the belief about the tangible and psychological costs of taking the health action.
• Cues to action are the triggers that prompt a person to take action.
• Self-efficacy is the belief in one's ability to successfully perform the recommended health behavior.
• The model is commonly used in public health interventions to promote preventive behaviors like vaccination and screening.

Theory of Planned Behavior

• Links beliefs and behavior.
• Attitude toward behavior, subjective norms, and perceived behavioral control shape an individual's behavioral intentions and behaviors.
• Attitude toward behavior is the degree to which a person has a favorable or unfavorable evaluation or appraisal of the behavior in question.
• Subjective norms are the belief about whether most people approve or disapprove of the behavior.
• Perceived behavioral control is the belief about how easy or difficult performance of the behavior is likely to be.
• Behavioral intention is an indication of an individual's readiness to perform a given behavior.
• Used to understand a wide range of behaviors, including health-related behaviors.

Cultural and Spiritual Models

• These recognize the influence of culture and spirituality on health and illness perceptions.
• Different cultures may have distinct beliefs about the causes of illness, and preferred treatments.
• Spiritual beliefs can provide meaning and support in coping with illness.
• Cultural competence is essential for healthcare providers to effectively communicate with and care for patients from diverse backgrounds.
• Cultural models may incorporate traditional healing practices, such as herbal medicine, acupuncture, or spiritual rituals.
• Neglecting cultural and spiritual factors can lead to misunderstandings and ineffective healthcare.

Explore theories of illness, including the biomedical model, which focuses on biological factors, and the biopsychosocial model, a more holistic approach. Understand how these frameworks shape medical practices and views on health. Learn about their impact on treatment strategies.