Weekend Catch-Up Sleep and Cancer Risk: What’s the Link?

There is no significant link between sleep duration and cancer risk, nor an association between catch-up sleep and cancer risk, according to the findings of a study published in the journal Sleep Health.

Using the Cancer Prevention Study 3 cohort (CPS-3), researchers investigated factors associated with cancer prevention and survival and whether sleep habits were associated with cancer risk among adults.

From 2006-2013, a total of 303,682 participants from 35 states in the United States, Puerto Rico, and The District of Columbia enrolled in CPS-3 with 254,650 participants completing the baseline survey. At the time of enrollment, participants were aged 35 to 65 years (mean age, 48 years; women, 77.7%) and had never received a cancer diagnosis other than basal and squamous cell carcinoma.

The researchers asked participants about their sleep duration on typical weekdays and weekends with possible responses being 0, < 1, 1-2, 3-4, 5-6, 7-8, 9-10, or 11+. The sleep duration category 7 to 8 was selected as a reference to align with the recommendations from the National Sleep Foundation. Weekend catch-up sleep (WCS) was calculated as the difference in weekend sleep duration minus weekday sleep duration with positive WCS indicating that the weekend sleep duration was longer.

Very few participants reported sleep durations in the extreme categories — 2921 in the weekday duration <5 hours and 536 in the weekday duration >10 hours, while the majority of the participants reported getting 7 to 8 hours of weekday sleep.

Non-White participants were more likely (22.1%) to get shorter hours of weekday sleep (5 to 6 hours) and women reported a longer weekend sleep duration. The majority of the participants (65.1%) had a WCS value of 0 hours.

Among this cohort, there were a total of 10,256 cases of cancer, including 3685 cases of breast cancer. However, sleep durations of 5 to 6 hours and 10 hours compared to 7 to 8 hours of sleep did not show any association with overall cancer risk regardless of sex.

Similarly, no associations with cancer were found when weekday and weekend sleep was assessed separately. WCS was also not associated with cancer risk. A small positive association was observed between weekday sleep duration of 3 to 4 hours and overall cancer risk, but this didn’t reach statistical significance. Another small positive association was found between breast cancer and WCS of 2 hours compared to no WCS.

The study also had a few limitations. Data on sleep was collected only once and was an approximation of sleep in the previous year. Researchers also assumed that weekdays and weekends meant workdays and non-workdays respectively and did not collect information on work schedules which can impact sleep.

Overall, the researchers noted there was no association between sleep durations and cancer risk.

“Future research should investigate how other sleep dimensions (i.e., timing, midpoint, chronotype, and quality), separately and in combination, may be associated with cancer risk,” the researchers concluded.

Read extensively about Stages 0-4 of Basal Cell Carcinoma