Logan Tuttle
Factors other than cancer treatment or chronic health conditions can influence the risk of death among survivors of childhood cancers, according to a study published in the Journal of Cancer Survivorship.
The researchers found an increased risk of death among cancer survivors who rarely exercised, were underweight, visited the doctor 5 or more times a year, considered themselves in “fair” or “poor” health, and had concerns about their future health.
Cheryl Cox, PhD, of the St Jude Children’s Research Hospital in Memphis, Tennessee, and her colleagues conducted this research using data from the Childhood Cancer Survivor Study.
The team compared 7162 childhood cancer survivors to 445 subjects who survived childhood cancer but ultimately died from causes other than cancer or non-health-related events (such as accidents).
The researchers matched subjects according to their primary diagnosis, age at the time of baseline questionnaire, and the time from diagnosis to baseline questionnaire.
Among the 445 subjects who died, the median age at death was 37.6 years. Malignant neoplasms (42%), cardiac conditions (20%), and pulmonary conditions (7%) caused the most deaths.
Subjects who died were slightly older than living subjects and more often of black race (vs white, Hispanic, or “other”). They were less likely to have a post-high school education or to be married. And they were more likely to have a household income below $20,000 or have an existing grade 3 or 4 chronic health condition.
When the researchers adjusted their analyses for sociodemographic characteristics, exposure to chemotherapy and/or radiation, and the number and severity of chronic health conditions, they identified a number of factors associated with an increased risk for all-cause mortality.
One of these factors was a lack of exercise—specifically, not exercising at all (odds ratio [OR]=1.72, P<0.001) or exercising 1 to 2 days a week (OR=1.65, P=0.004), compared to exercising 3 or more days a week.
On the other hand, being overweight or obese did not significantly increase a subject’s risk of death, but being underweight did (OR=2.58, P<0.001).
As one might expect, increased use of medical care was associated with an increased risk of mortality.
Subjects who reported 5 to 6 doctor visits per year had twice the risk of death as subjects who reported 1 to 2 visits (OR=2.07, P<0.001). And subjects who reported more than 20 annual doctor visits had a nearly 4-fold greater risk of death than subjects who reported 1 to 2 visits (OR=3.87, P<0.001).
Similarly, subjects had an increased risk of mortality if they described their general health as being “poor” or “fair” (OR=1.98, P<0.001). And being “concerned” or “very concerned” about future health was associated with an increased risk of mortality as well (OR=1.54, P=0.01)
On the other hand, smoking did not have a significant impact on the risk of death, and alcohol consumption appeared to have a positive impact on life expectancy.
Subjects who reported consuming 5 or more drinks per month had a lower risk of mortality than subjects who said they did not consume alcohol at all (OR=0.75, P=0.05).
Dr Cox and her colleagues said this research has revealed novel predictors of mortality not associated with a cancer survivor’s primary disease, treatment, or late effects. And continued observation could point to interventions for reducing the risk of death in these patients.
