Cancer patients in chemo ward may influence each other's survival

(Reuters Health) - Who a cancer patient spends time with in the chemotherapy ward may have a small but significant effect on their likelihood of surviving the disease, suggests a small study in the UK.

Researchers found that patients who received chemo alongside others who survived for five years or longer were more likely to survive for at least five years themselves, while patients surrounded by peers who survived for less than five years were also more likely to die within five years of their diagnosis.

“Social influence in the chemotherapy ward matters, and specifically it has both positive and negative effects,” lead author Jeff Lienert, a fellow at the U.S. National Human Genome Research Institute’s Social and Behavioral and Research Branch, told Reuters Health in a telephone interview. “It’s a stronger effect if the time is concentrated among a few people, rather than spread out over a lot of people.”

Cancer patients who receive chemotherapy intravenously typically spend hours in an outpatient clinic or ward as the drug is infused, over the course of several weeks. These wards often have an open design, so patients see others receiving treatment and may interact with them.

Studies have found that cancer patients with stronger social networks may live longer, particularly female patients, Lienert and his team write in the journal Network Science. In the new study, they investigated whether social encounters in the chemotherapy ward might have also an impact on patients’ survival.

They studied patients treated at one UK hospital’s chemo ward, which consisted of two treatment rooms with 10 beds and six chairs arranged in a circle, along with privacy screens.

Lienert and his team used statistical techniques to build a network showing how much time 4,691 patients treated from January 1, 2000 to January 1, 2009 spent in one another’s company while receiving treatment.

Among the patients who were in the ward with others who died within five years of chemo, 72 percent also died within five years. But among patients who encountered another patient who survived for five years or longer, 68 percent died within five years.

The researchers estimate that patients who were isolated from others while receiving chemo would have had a 69.5 percent chance of surviving for five years. Thus the effect of spending time with people who survived longer is approximately an extra 2 percent improvement in survival odds. For comparison, choice of chemotherapy drug is estimated to have about an 8 percent effect on survival, the study team notes.

While an extra 2 percent chance of survival compared to isolation may not seem like much, Lienert pointed out, in the current study that added up to about 100 additional survivors.

The researchers tried to account for other factors that might explain this survival difference, including the fact that some patients might have known each other already, so their friendship outside the chemo ward would likely be the source of any positive effects.

Another possibility is that differences in nurses working in the chemo ward at different times have an effect, but if that’s true, then the study detected a “meaningful nurse effect” that hasn’t been previously reported and should be studied further, the authors write.

Most likely, Lienert and his colleagues suggest, the differences they observed are due to stress. It is likely to be stressful to see other cancer patients who are not faring well, while it may ease stress to see others whose treatment seems to be more successful, they explain.

Trying to reorganize chemotherapy wards and patient scheduling in order to take advantage of the findings would be a complex proposition with the potential for unintended consequences, the researcher note. But there are simple ways to take advantage of the social survival boost seen in the study, Lienert said.

For example, cancer survivors could volunteer to spend time with people receiving chemotherapy, and cancer patients can ask a supportive friend or family member to accompany them. “That’s something that patients can control on their own that would take advantage of these results,” Lienert said.

SOURCE: Network Science, online July 12, 2017.