Childhood cancer survivors at increased risk for sleep concerns decades after diagnosis

Key takeaways:

• One-third to 40% of the study population reported insomnia symptoms.
• Cognitive behavioral therapy for insomnia is needed to reduce sleep medication use.

INDIANAPOLIS — Compared with siblings, survivors of childhood cancer have an increased risk for sleep concerns up to 30 years after diagnosis, according to a report from the Childhood Cancer Survivor Study.

What’s more, a history of childhood cancer appears to increase the risk for sleep concerns about 20% above known demographic risk factors, according to Lauren C. Daniel, PhD, associate professor of psychology and health sciences at Rutgers University-Camden, who presented her findings.

“But,” Daniel said, “those demographic risk factors are probably the ones that are helpful in helping us identify and triage who needs attention for sleep.”

The multicenter, cohort Childhood Cancer Survivor Study includes data for patients treated in the 1970s, ’80s and ’90s, with data collected at two time points. In the session here, Daniel reported on the most recent data collected, which included 12,340 survivors and about 2,400 siblings who continued with the cohort.

The Pittsburgh Sleep Quality Index was mailed to all survivors and Daniel and colleagues used additional analyses to look at sleep duration less than 6 hours, insomnia symptoms, self-reported snoring of greater than three times per week, estimated circadian delay and sleep medication use. The researchers also received data on treatment exposures from patients’ care institutions, which they used to look for predictors.

The average ages of survivors and siblings were 39 and 44 years, respectively. The average age at cancer diagnosis was 8 years and the average time since diagnosis was 31 years. In terms of cancer type, the most common groups were leukemia at 32% of survivors, followed by central nervous system (14%) and Hodgkin’s (12%) lymphomas.

Daniel and colleagues compared sleep behaviors between survivors and siblings and adjusted for age, sex, race and BMI. According to the results, survivors had an increased risk for every domain of sleep concerns, including sleep duration, sleep quality and insomnia.

“It’s interesting that, as a clinical psychologist, insomnia symptoms were the most commonly reported; at least one-third to about 40% of the sample were reporting different symptoms of insomnia,” Daniel said.

To understand the role of diagnosis and treatment exposures, researchers conducted two multivariable models. The findings for demographic factors were similar to those in the general population: Women were at risk for poorer sleep quality and sleep medication use and a decreased risk for snoring; BMI was linked to an increased risk for snoring; and, interestingly, according to Daniel, obesity was linked to poorer sleep quality and sleep medication use.

In terms of race and ethnicity, Black, Hispanic and Asian survivors were less likely than white survivors to use sleep medications. For age at survey, findings were similar to the general population, as well: As survivors aged, snoring was more common and they were less likely to have a delayed bedtime. And age at diagnosis showed younger adolescents reported an increased risk for poor sleep quality, and both age groups were more likely to use sleep medications.

There was no link between diagnostic group and sleep outcomes, but Daniel reported a reduced risk for snoring and delayed bedtime among CNS tumor survivors.

“We saw that similar circadian pattern in the first wave of this data,” she said. “So, perhaps these [survivors] are more tired, whether they’re more likely to be getting more sleep, extending their sleep or potentially shifted the other way that something is happening there. We need to dig a little bit more into that.”

In the second model, which controlled for the same demographic factors, Daniel said they saw significant treatment exposures. Specifically, high-dose anthracyclines were related to poor sleep quality, history of vincristine was linked to a lower likelihood of medication use, and cranial radiation was associated with less sleep medication use. A “relatively novel finding,” she said, was a reduced likelihood of snoring among those who underwent neck radiation.

“This is potentially due to some of that musculature hyperplasia that may be happening,” she said.

Lastly, survivors who were exposed to abdominal radiation had a greater likelihood of snoring and poor sleep quality and delayed bedtime. “Those with abdominal radiation are probably the ones we need to be especially screening, as well as high BMI in men for snoring and disordered sleep breathing,” Daniel said. No other exposures were significant.

“About 40% of patients report sleep concerns, and it doesn’t really go away despite what patients tend to think: ‘I’ll worry about sleep when treatment is over.’ We’re seeing it even at 30 years post-diagnosis, that they have a higher risk of sleep concerns relative to siblings.”

According to Daniel, cognitive behavioral therapy for insomnia (CBTi) is a much-needed intervention among this population, whose use of sleep medications is higher than the national average based on survey data from 2020.

“This is a group in great need of CBTi and substantially earlier than 30 years after their diagnosis.”