Introduction to Health Psychology and the Biopsychosocial Model

The Biopsychosocial Model

Modern health psychology has moved away from this dualism toward the Biopsychosocial (BPS) Model. Unlike the traditional biomedical model, which is reductionistic and focuses on single causal factors (like a virus or a chemical imbalance), the BPS model assumes that health is influenced by the coordinated interaction of three levels:

1. Biological factors: Neurophysiology, genetics, and cellular processes.
2. Psychological factors: Emotions, personality, and cognitive processes.
3. Social factors: Socio-economic status, culture, and social support.

The BPS model utilizes "systems theory," suggesting that all levels of organization—from micro-level chemical imbalances to macro-level social environments—are linked. A change in one level will inevitably affect the others.

The Core Focus of Health Psychology

Health psychologists do not just study diseases; they apply psychological principles across a wide spectrum of health-related activities. Their work generally falls into four key areas:

• Health promotion and maintenance: Investigating how to encourage healthy behaviors and maintain well-being.
• Prevention and treatment of illness: Developing strategies to stop diseases before they start and improving how we treat them once they occur.
• Etiology and correlates of health, illness, and dysfunction: Studying the causes (etiology) of illness and the various factors (correlates) that make certain people more or less susceptible to disease.
• Improving the health care system and policy: Using psychological insights to make healthcare delivery more effective and to influence public health policy.

Exam Tip: When comparing models, remember that the Biomedical model is reductionistic (breaking things down to the smallest physical part), while the Biopsychosocial model is integrative (looking at the whole person in their environment).

Why This Matters: The Changing Landscape of Disease

The importance of health psychology is underscored by a significant shift in global mortality patterns. In the past, acute infectious diseases were leading causes of death. However, as medical technology has improved, there has been a shift toward chronic illnesses.

Figure 1.3: Death Rates for the Leading Causes of Death in Canada, 1921-25, 2011, and 2019.

As we look toward the future, the prevalence of chronic conditions like ischemic heart disease, cerebrovascular disease, and diabetes is expected to remain high. Because these chronic conditions are heavily influenced by lifestyle, stress, and social environments, the psychological component of medicine becomes increasingly vital to managing public health in the 21st century.