Top Takeaways from ASCO: Childhood Cancer Survivor Study and smoking interventions

Despite a drop in smoking prevalence among survivors of childhood cancer, the considerable proportion of consistent, current smokers that does exist demonstrates a need for ongoing development of effective smoking interventions in this population.

“Childhood cancer treatments are associated with increased risk for a number of health problems that are also known to be associated to smoking,” Todd M. Gibson, PhD, of the department of epidemiology and cancer control at St. Jude Children’s Research Hospital, told Healio.com. “While smoking is bad for everyone, it may be particularly harmful in survivors.”

Todd M. Gibson

Gibson and colleagues from other institutions examined self-reported smoking status in 10,430 adults included in the Childhood Cancer Survivor Study.

The investigators analyzed data from two questionnaires, separated by a median time of 7.9 years (range 1.4-11.9). They compared smoking prevalence among cancer survivors with their siblings and with the expected rate in the U.S. general population, taking age, sex, race/ethnicity and calendar time into account.

Using multivariable regression models, the researchers assessed characteristics associated with longitudinal smoking patterns in 3,908 survivors who completed each of three questionnaires over a median time interval of 12.5 years (range 4.3-16.3).

The baseline rate of current smokers was 19% among survivors compared with 24% among siblings and 29% expected based on U.S. population rates. At the initial follow-up, 17% of survivors reported being current smokers compared with 21% of their siblings and 24% expected based on the U.S. population.

Three characteristics were associated with consistent “never smoking” across all questionnaires:

higher household income (RR = 1.17; 95% CI, 1.08-1.25 for ≥ $60,000 vs. < $20,000 per year)
higher education (RR = 1.36; 95% CI, 1.26-1.47 for > high school vs. ≤ high school); and
undergoing cranial radiation therapy (RR = 1.10; 95% CI, 1.05-1.16).

Among ever smokers, higher income was associated with quitting (RR = 1.22; 95% CI, 1.09-1.38) as was education (RR = 1.26; 95% CI, 1.13-1.4); however, cranial radiation was associated with not quitting (RR = 0.85; 95% CI, 0.76-0.96).

The investigators found no association between developing an adverse health condition and subsequent changes in smoking patterns.

“While it is encouraging to see a modest decline in smoking over time, the take-home message from this study is that a substantial number of survivors continue to smoke despite being at elevated risk for health problems such as cancer and heart or lung disease,” Gibson said. “Prevention and cessation are challenging, just as they are in the general population, but clearly further efforts are warranted in this high risk group.” – by Allegra Tiver

For more information: Gibson TM, et al. Abstract 10075. Presented at: ASCO Annual Meeting. May 29-June 2, 2015; Chicago.

Disclosure: Gibson reports no relevant financial disclosures.