Stressors, Stress Response, and Cancer Recurrence

A Systematic Review

Briana L. Todd, MA, MS; Michal C. Moskowitz, MS; Alicia Ottati, MA; Michael Feuerstein, PhD, MPH

Disclosures

Cancer Nurs. 2014;37(2):114-125. 

In This Article

Results

As Figure 1 indicates, of 1067 (990 when excluding duplicates) potential papers on stressor exposure and/or stress response and cancer recurrence, only 15 articles met the inclusion criteria.[22–36] These studies are summarized in the Table. As the Table indicates, there were 2 studies published from the 1970 to 1989 period, followed by 5 in the decade between 1990 and 1999, 6 studies between 2000 and 2009, and 2 thus far since 2010. Three studies were randomized control trials (RCTs). However, 2 of these studies followed the same participants over time.[22,23] Although we did not limit the review to any specific types of cancer, 12 of 15 studies researched breast cancer and 3 of 15 examined melanoma. One study included biological measures of stress response (ie, cortisol and catecholamines). Five studies assessed biological measures of immunological activity associated with stress response. Six of the articles used environmental measures of recent life events as the index of stressor exposure, and 13 used measures of the psychological response to stress (eg, distress, depressive symptoms, anxiety symptoms).

The findings related to stress and cancer recurrence are illustrated in Figure 2. As the figure indicates, most of the studies (12/15) reported finding no relationship between cancer recurrence and at least 1 measure of stress. Ten studies reported exclusively null or even inverse findings. Three studies reported at least 1 finding of an inverse relationship between stress and cancer recurrence (ie, higher stress predicted lower recurrence). One study exclusively reported an inverse relationship between stress and recurrence. Five of 15 studies reported a positive association between cancer recurrence and stress, of which only 2 studies exclusively reported a positive finding and 3 reported mixed findings. When considering the 9 studies (7 longitudinal trials and 2 RCTs) that included multiple dimensions of stress (ie, environmental, biological, and psychological), 3 studies indicated a positive relationship between stressor exposure and/or stress response and cancer recurrence. The data points in Figure 2 exceed 100% of the studies because certain studies had multiple findings.

Figure 2.

Summary of individual findings related to stress and cancer recurrence. This figure provides a summary of studies investigating stress and cancer recurrence (N = 15 studies). Studies often had multiple outcomes. Biological measures of stress response = endocrine levels and white blood cell count. Biological measures of immune function = natural killer cell activity/natural killer cell count. Psychological/psychosocial measures of stress response = self-report measures of stress response, such as symptoms of depression or anxiety. Environmental stressors = occurrence of stressful life events.

Findings differed by the dimension of stress assessed in each study (environmental, psychological, and biological). None of the 5 studies using environmental measures of stressor exposure (acute stressful life events and/or chronic stressors) reported a positive relationship between stressor exposure and cancer recurrence. On the contrary, 1 study found a significant inverse relationship whereby greater exposure to stressful events predicted nonrecurrence.[27] Of the 13 studies assessing psychological stress response, 4 reported at least 1 positive finding, 7 reported exclusively null findings, and 1 reported an inverse finding. Of the studies using a biological measure of immune function, 2 reported mixed findings (1 reported both inverse and null results and 1 reported both positive and null results) and 5 found no association between stressor exposure and/or stress response and cancer recurrence. Only 1 study used a biological correlate of the stress response (ie, cortisol, catecholamines), and it reported mixed null and positive findings.

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