Importance of Links with Stress

Not all health behaviors are related to stress. Even when behaviors are linked with stress, there are typically many other influences on the frequency and intensity of the activity. Health behaviors are embedded within a complex sociocultural matrix, with factors such as tradition, legislation, taxation, income, and systems of provision all influencing lifestyle and health behavior.

Thus, alcohol use is not only modified by stress, but also is related to religious and social traditions, costs relative to disposable income, family experiences and peer group influences, and individual attitudes and habits. Leisure-time physical activity can be used as a way of coping with stress, but is also affected by other motives such as interest in sport and concern about appearance and by availability of a safe place to exercise, cost, time constraints, health status, and cultural attitudes.

Nevertheless, stress does have a significant role in many health behaviors, and this can be important for understanding associations between stress and health. The reason is that if stress does increase the occurrence of a health risk behavior or decreases a positive health behavior, then these behaviors may mediate the influence of stress on health risk. Indeed, changes in behavior sometimes play a more important role in the stress-health relationship than neuroendocrine, autonomic, and immunological responses.

For instance, one study evaluated the impact of work stress on the development of hypertension (high blood pressure) over a 5 year period among male air traffic controllers. Some 20% of the air traffic controllers who initially had normal blood pressure developed hypertension during the study. This might be assumed to have been the result of sustained neuroendocrine and autonomic activation elicited by working in this responsible and stressful job.

However, it was found that alcohol consumption also rose in individuals who became hypertensive, and it was this factor that accounted for the increase in blood pressure. Thus, the association between work stress and cardiovascular disease was mediated by a health-related behavior rather than by activation of biological stress pathways.

Other examples can be found in the epidemiological literature on psychosocial factors and health risk. A study reported by Everson and colleagues of a large sample of middle-aged men in Finland explored associations between hostility and cardiovascular disease mortality over a 9 year period It was found that high levels of hostility measured at the beginning of the study predicted cardiovascular mortality independently of known risk factors such as cholesterol and socioeconomic status.

However, when smoking, alcohol consumption, body mass index, and physical activity were taken into account, the association between hostility and mortality was diminished substantially. This suggests that the influence of hostility was mediated not by neuroendocrine pathways, but rather by differences in health behaviors. The more hostile individuals were also those who smoked, drank alcohol excessively, and were overweight and physically inactive, which accounted for the increase in cardiovascular risk.

Health behaviors also influence links between stress and health outcomes in patients with medical conditions. One important health behavior in many illness states is adherence to medication and health advice. Low adherence can result in ineffective treatment and risk to future health. Poor adherence is affected by life stress and by states of subjective distress and depression. This might explain why, for instance, cardiac patients who suffer depression and distress following a myocardial infarction are at increased risk for recurrent cardiac events.

Thus, the relationship between health behavior and stress is of interest not only in itself, but also for its role in mediating health effects.