Behavioural sciences chapters
Stress, stressors, life events and illness
What stress is, the types of stress and stressors, how the body responds (fight or flight and the general adaptation syndrome), how life events and chronic stress lead to illness, and the main ways of managing stress.
- Stress is the body's and mind's response when demands (stressors) seem to exceed a person's ability to cope; mild stress that motivates is eustress, harmful stress is distress.
- The body responds with the fight-or-flight reaction (sympathetic, adrenaline) and the HPA axis (cortisol); Selye's general adaptation syndrome has three stages: alarm, resistance, exhaustion.
- Major life events (Holmes and Rahe scale; death of a spouse scores highest) and chronic stress raise the risk of physical and mental illness; stress is managed by changing the stressor, the appraisal and the response.
On this page
Overview
Stress is part of everyday life, and of a doctor's life in particular. A little stress sharpens performance; too much, for too long, damages physical and mental health.
Definitions
- Stressor: any demand or event that requires adjustment (an exam, an illness, a death, noise, poverty).
- Stress: the physical and psychological response that occurs when a person perceives that demands exceed their ability to cope.
Stress depends on appraisal: the same event (a viva) may be a challenge to one student and a threat to another. Lazarus described primary appraisal (is this a threat?) and secondary appraisal (can I cope?).
Eustress and distress
- Eustress: positive, optimal stress that motivates and improves performance (preparing for an exam, a wedding, a new job).
- Distress: negative stress that overwhelms and harms.
Yerkes-Dodson law
Performance improves with arousal up to an optimal level, then falls (an inverted U). Complex tasks need lower arousal than simple ones.
Yerkes-Dodson law: performance is best at moderate arousal; too little or too much lowers it.
Classification of stress and stressors
| By duration | By nature | By source |
|---|---|---|
| Acute (sudden, short: an accident) | Physical (injury, heat, noise, illness) | Personal (illness, exams) |
| Episodic (repeated acute stress) | Psychological (fear, conflict, frustration) | Family (marital conflict, bereavement) |
| Chronic (long-lasting: poverty, chronic illness, caring for a disabled child) | Social (unemployment, discrimination, isolation) | Occupational (workload, night shifts) |
| Environmental (crowding, pollution, disasters) | Societal (violence, political unrest) |
Stressors may be major life events or minor but frequent daily hassles (traffic, load-shedding, queues); daily hassles can add up to as much harm as major events.
The body's response to stress
Fight-or-flight (Cannon)
The sympathetic nervous system and adrenal medulla (adrenaline and noradrenaline) act within seconds: faster heart, higher blood pressure, faster breathing, raised blood glucose, dilated pupils, sweating, blood diverted to muscles, slowed digestion.
The HPA axis
Hypothalamus (CRH) → pituitary (ACTH) → adrenal cortex (cortisol). Cortisol raises glucose and suppresses inflammation and immunity. Short-term it helps; long-term high cortisol is harmful.
Selye's general adaptation syndrome (GAS)
| Stage | What happens |
|---|---|
| 1. Alarm reaction | Fight-or-flight; resources mobilised; resistance briefly falls |
| 2. Resistance | The body adapts and copes; high hormone levels continue |
| 3. Exhaustion | Resources are used up after prolonged stress; illness develops ("diseases of adaptation") |
Selye's GAS: alarm → resistance → exhaustion.
Life events and illness
Holmes and Rahe (1967) developed the Social Readjustment Rating Scale, giving each life event a score in life change units (LCUs):
| Life event | Score |
|---|---|
| Death of a spouse | 100 (highest) |
| Divorce | 73 |
| Marital separation | 65 |
| Imprisonment | 63 |
| Death of a close family member | 63 |
| Personal injury or illness | 53 |
| Marriage | 50 |
| Dismissal from work | 47 |
Even positive events (marriage, promotion) need adjustment and score points.
A total of over 300 LCUs in a year is linked with a high risk of illness in the following period; 150–299 moderate risk.
In one year a man: loses his wife (100), suffers an injury (53), is dismissed from work (47), and has a death of a close family member (63)
Total = 100 + 53 + 47 + 63 = 263 LCUs → moderate risk (150–299)
Add marriage the next year (50) within the same 12 months → 313 LCUs → high risk (over 300)
The scale shows an association between life change and illness; it does not prove that stress alone causes disease, and coping and support change the effect.
How stress causes illness
- Physiological: raised BP and heart rate, high blood glucose, inflammation; long-term high cortisol suppresses immunity (more infections, slower wound healing). This is studied in psychoneuroimmunology.
- Behavioural: smoking, alcohol and drug use, poor diet, less exercise, poor sleep, poor adherence to treatment.
- Psychological: anxiety, depression, burnout, post-traumatic stress disorder.
Conditions linked or worsened by stress: hypertension, coronary heart disease, peptic ulcer symptoms, irritable bowel syndrome, asthma, eczema and psoriasis flares, tension headache, infections, and many psychiatric disorders.
Stress management
Change the stressor: problem solving, time management, planning, saying no.
Change the appraisal: cognitive restructuring (seeing the situation more realistically), positive thinking, spiritual and religious coping.
Change the response:
- Relaxation techniques: deep breathing, progressive muscle relaxation, meditation, prayer.
- Regular exercise, sleep and a healthy diet.
- Social support: family, friends, colleagues.
- Avoiding harmful coping (smoking, drugs).
- Professional help: counselling, cognitive behavioural therapy, treatment of depression or anxiety.
See coping and defence mechanisms.
Expect: the definition of stress and the role of appraisal, eustress vs distress, Yerkes-Dodson law, classification of stressors, fight-or-flight and the HPA axis, Selye's three stages, the Holmes-Rahe scale (death of spouse = 100; over 300 high risk), how stress causes illness, and stress management methods.
Quick revision
- Stress: demands perceived to exceed coping; appraisal matters (Lazarus).
- Eustress motivates; distress harms; Yerkes-Dodson inverted U.
- Fight or flight: sympathetic, adrenaline. HPA: CRH → ACTH → cortisol.
- Selye's GAS: alarm, resistance, exhaustion.
- Holmes-Rahe: death of a spouse 100; over 300 LCUs high risk.
- Manage: change the stressor, the appraisal, the response; social support.
Written by The House Job from the Handbook of Behavioural Sciences by Mowadat H Rana (named in the UHS PGET syllabus).
FAQ
What is the difference between eustress and distress?
Eustress is positive, motivating stress; distress is harmful stress that overwhelms coping.
What are the stages of the general adaptation syndrome?
Alarm, resistance and exhaustion, as described by Hans Selye.
Which life event has the highest score on the Holmes and Rahe scale?
The death of a spouse, scored at 100 life change units.
How can stress cause physical illness?
Through hormonal and immune changes such as raised cortisol, and through harmful behaviours such as smoking, poor diet and poor sleep.