Stress and Illness

Stress. Most of us feel it with some regularity. We typically think in terms of difficult life circumstances – e.g., financial reversals, work-related challenges, loss of social standing, relationship issues, illness. But it can also accompany welcome life events – e.g., marriage, promotions, buying houses, retirement, vacations.

stressed outI don’t like to admit to feeling stressed. I prefer to think that I have everything under control. That whatever life is throwing at me, I’ve got it covered. And I don’t like slowing down when I’ve got a full head of stream or taking things off my plate when I’m busy. Stress can be an unpleasant wake-up call that I’m not interested in answering.

Back in the 1960s, folks started taking an interest in the relationship between stress and illness. Psychiatrists Thomas Holmes and Richard Rahe examined the medical records of thousands of patients and correlated the incidence of illness with various life events. They published the following Holmes and Rahe Stress Scale through which the sum of change units in a given year provided an indication of the relative risk of illness. A score of 300+ suggested a high risk of illness, 150-299 moderate, and <150 slight.

Life Event Change Unit Life Event Change Unit
Death of a spouse 100 Child leaving home 29
Divorce 73 Trouble with in-laws 29
Marital separation 65 Outstanding personal achievement 28
Imprisonment 63 Spouse starts or stops work 26
Death of a close family member 63 Beginning or end of school 26
Personal injury or illness 53 Change in living conditions 25
Marriage 50 Revision of personal habits 24
Dismissal from work 47 Trouble with boss 23
Marital reconciliation 45 Change in working hours or conditions 20
Retirement 45 Change in residence 20
Change in health of family member 44 Change in schools 20
Pregnancy 40 Change in recreation 19
Sexual difficulties 39 Change in church activities 19
Gain a new family member 39 Change in social activities 18
Business readjustment 39 Minor mortgage or loan 17
Change in financial state 38 Change in sleeping habits 16
Death of a close friend 37 Change in number of family reunions 15
Change to different line of work 36 Change in eating habits 15
Change in frequency of arguments 35 Vacation 13
Major mortgage 32 Major holiday 12
Foreclosure of mortgage or loan 30 Minor violation of law 11
Change in responsibilities at work 29

The system purportedly had value for folks like me who might ignore the signs of stress but rack up sufficient stressors to warrant a moment or two of consideration. Having run across this system recently, I got to thinking: Has their research stood the test of time?

An article by Cohen, Murphy, and Prather on stressful life events and disease risk provided several insights based on 70 years of research on the subject. Here are their findings:

  1. Stressful events may arise based on the amount of adaptation or change required of an individual, the imminence of threat or harm, a level of demand exceeding resources, an interruption of goals, or any combination thereof.
  2. Stressful events influence disease onset through a variety of mechanisms. As discussed in a prior post, excess stress may lead to hypertension, high cholesterol, disrupted digestion, bone disintegration, suppression of immune function, and neural network damage. The affected individuals may also adopt poor health behaviors as coping mechanisms – e.g., faulty nutrition, poor exercise habits, substance abuse, dysfunctional sleep patterns.
  3. Most people exposed to stressful events do not get sick. And despite increased risk for mental disorders, stress does not necessarily lead to depression. People with greater perceived control, self-efficacy, and a generally optimistic outlook tend to be resilient.
  4. Excluding natural disasters, stressful event exposure correlates with socioeconomic status (i.e., low status yields more events) and personality factors (e.g., agreeableness, conscientiousness, positive or negative attitude, attachment styles, neuroticism).
  5. Stressful events may not cause disease in otherwise healthy people. Nonetheless, biological wear and tear caused by chronic stress may result in increased disease risk, and stress may tip the balance toward disease in a system made vulnerable by other causes.
  6. Certain stressors are more impactful than others, notably those which threaten an individual’s sense of competence or standing in areas that reflect the individual’s core identity. These stressors generally fall within the domains of interpersonal problems, social status, and work difficulties. In particular:
    • Stressful interpersonal events have been associated with heightened risk of depression, upper respiratory infection, hypertension, heart disease, physical disability, and premature mortality.
    • Folks experiencing social rejection have shown decreased anti-inflammatory gene signaling and increased asthma symptoms.
    • Unemployment and underemployment has been associated with increased risk of depression, cardiovascular disease, and premature mortality. Even a month’s worth of unemployed and underemployment increases susceptibility to cold-causing viruses.
  7. As a rule, persistent stress and chronic intermittent stress prove more deleterious than acute stress. Acute stress proves problematic when it accelerates a pre-existing disease process or sets off longer-term trauma (e.g., rape).
  8. Multiple events may or may not be more potent than individual ones. Studies have not done a good job accounting for multiple distinct stressors versus several events tied to a single root cause (e.g., divorce and associated changes in financial status, residence, church, social circles, recreation, etc.)
  9. The impact of stressful events varies as a function of when they occur during a life. For example, the death of a spouse at middle age with teenaged children proves more impactful than in one’s senior years. Moreover, there are sensitive periods in life when stressors exact a higher toll, notably childhood.
  10. Men and women respond to stress differently based on evolutionary pressures and cultural norms.