OSA common in women with breast, endometrial cancers

Obstructive sleep apnoea (OSA) is common among postmenopausal women with breast cancer (BC) or endometrial cancer (EC), a recent study has found.

Researchers conducted a cross-sectional analysis of 50 women with BC (mean age 59.6±8.7 years) and 37 with EC (mean age 60.3±7.7 years). Participants were enrolled 12 and 3 months after diagnosis, respectively, and sleepiness was assessed using the Epworth Sleepiness Scale (ESS). A STOP-BANG* score >3 was used to judge OSA.

Comparing sleep architecture between the two groups, the researchers found no significant difference in terms of total sleep time and sleep efficiency. ESS scores were likewise comparable between groups.

On the other hand, BC participants had longer sleep latency (31.8±32 vs 19.3±17.9 minutes; p=0.03), greater proportion of rapid eye movement sleep (21.1±6.9 percent vs 16.6±5.7 percent; p=0.02), and less slow wave sleep (20.0±5.2 percent vs 23.6±8.2 percent; p=0.02).

In terms of sleep-disordered breathing and hypoxia metrics, EC patients showed significantly lower average oxygen saturation level at an upright awake seated position (94.6±1.9 percent vs 95.6±1.3 percent; p=0.003) and while asleep (93.3±2.5 percent vs 94.8±2.1 percent; p=0.006) than BC counterparts.

Overall STOP-BANG score was significantly lower in BC patients (2.6±1.5 vs 3.4±1.7; p=0.04), though the percentage of those with scores >3 was comparable between groups (46 percent vs 57 percent; p=0.27). Clinicopathological tumour characteristics were not linked with OSA metrics.

The apnoea-hypopnoea index was also similar between groups (21.2 vs 15.7 events per hour; p=0.733), though 58 percent and 57 percent of BC and EC women, respectively, saw >15 events per hour.

“Women with BC or EC have a high prevalence of moderate-severe OSA that may go unrecognized, potentially due to a lack of sleepiness symptoms and an atypical presentation,” the researchers said.

“OSA likely poses an increased anaesthetic and surgical risk for these patients during their treatment phase and should also be considered as a potential contributor to on-going quality of life issues that may be experienced by … patients in the post-treatment phase,” they added.

*Snoring history, tired during the day, observed stop breathing while sleep, high blood pressure, body mass index more than 35 kg/m², age more than 50 years, neck circumference more than 40 cm, and male gender.