Optimism may smooth breast cancer recovery

One of the summer jobs I had during college was working for the Fred Hutchinson Cancer Research center in Seattle. My job was to do data entry for a breast cancer study; it was simultaneously one of the most boring and depressing jobs I ever had. I sorted through the medical records of hundreds of women, found their chemotherapy dosage regimens, then entered their dosages for weeks and weeks of therapy. For accuracy, I had to enter all the data twice. Even as I was entering the data, I could notice a pattern: the women who completed their entire chemotherapy regimens lived, and those who did not, died. When the study was finally published a couple years later, the results bore this out.

So what motivates some women to complete their treatment and rebuild their lives, while others fail, and often die? A team led by Charles Carver has begun to explore some aspects of this troubling problem: they wanted to know the impact of an optimistic disposition on how women handle breast cancer treatment. Previous research has found that optimistic people are more likely to continue exercise in cardiac rehabilitation, and tend to take a more active problem-solving approach than pessimists. So how does optimism impact breast cancer patients?

Their first study involved 235 post-surgery patients. 138 had lumpectomies and 97 had mastectomies, and all underwent some combination of chemotherapy and radiation treatment. They were assessed for optimism-pessimism, social disruption, emotional distress, and fatigue. Pessimism was significantly correlated with all three measures. However, because the study was only administered after the surgeries, it was impossible to know whether the pessimism caused the fatigue and distress, or vice versa.

A second study tracked 97 women for more than a year after their surgery. They were tested about 1 month, 4 months, 7 months, and 16 months after the surgery. While this still doesn't get at the key measure of how optimism before surgery affected recovery, it's certainly better than a one-time test. Social disruption was viewed by the researchers as the key measure, because other studies have found that when patients with a variety of conditions are able to resume their normal social lives, overall mental health improves concurrently. The researchers asked respondents how strongly they agreed with statements like "I am going out less to visit people," and "I talk less with those around me." Responses were combined in an index and correlated with both pessimism and whether the patient was undergoing chemotherapy. Here are those results (correlations in red are significant):

As you can see, pessimism was a better predictor of social disruption than engagement in chemotherapy. Additional analysis revealed that pessimism predicted later distress even when earlier distress was controlled for, suggesting that pessimism was indeed part of the cause of the later distress.

The effects reported in this study are relatively small, but they do point to the importance of personality in recovery from medical treatment. I'd be interested to see if longer-term follow up work can demonstrate a relationship between personality and survival rates.

Carver, C.S., Lehman, J.M., & Antoni, M.H. (2003). Dispositional pessimism predicts illness-related disruption of social and recreational activities among breast cancer patients. Journal of Personality and Social Psychology, 84(4), 813-821.