Prevalence and characteristics of sleep disordered breathing in pre- and post-menopausal women

Abstract

Historical studies suggest that there is an increased male/female ratio in the prevalence of sleep disordered breathing (SBD). Moreover, SDB was reported to increase in postmenopausal women. The aim of this study was to assess the prevalence and the characteristics of SDB in pre-menopausal and post-menopausal women. 2114 subjects (50.4% women, 58.5 ± 10.7 y.o, BMI 26.2 ± 4.4 kg/m 2 ) participating in an ongoing population-based sleep cohort study (HypnoLaus, Lausanne, Switzerland) underwent full polysomnographic recordings at home. They also had a complete clinical workup including metabolic, cardiovascular, genetic and morphometric evaluation. Hormonal status was recorded in 981 women (30.6% pre-menopausal and 69.4% post-menopausal). Respiratory events were scored according to the AASM 2013 criteria. The prevalence of SDB in women with AHI thresholds of 5/h, 15/h and 30/h was 60.9%, 22.8% and 7.5%. Prevalence of an Epworth score > 10 and SDB with the same thresholds was 18.9% (AHI > 5/h), 11.5% (AHI > 15/h) and 5% (AHI > 30/h) with a male/female ratio of 1.75, 2.4 and 2.8 respectively. Male vs female prevalence was significantly different in each severity group ( p < 0.0001). Compared to men, women with an AHI > 15/h were older ( p < 0.0001), had a lower neck circumference ( p = 0.0001), a lower Mallampati score ( p = 0.0001), a lower waist/hip ratio ( p < 0.0001) but the BMI was not significantly different: 28.2 kg/m 2 in women vs 28.1 kg/m 2 in men ( p = 0.711). Women also reported less sleepiness at the wheel ( p < 0.0002), less witnessed sleep apnea ( p = 0.0006) but more morning fatigue ( p = 0.034), more sleeping pill intake ( p = 0.0003) but the same rate of snoring ( p = 0.55). Compared to post-menopausal, pre-menopausal women had a lower SDB prevalence. AHI > 5/h: 26.6% vs 42.5% ( p < 0.0001), AHI > 15/h: 7.2% vs 18.6% ( p < 0.0001), AHI > 30/h: 1.3% vs 10.2% ( p < 0.0001). Post-menopausal women had a larger neck ( p = 0.006) a higher waist-hip ratio ( p = 0.0001) and a higher Mallampati score ( p = 0.009) but the BMI was not significantly different( p = 0.5). The prevalence of SDB is lower in women than in men with a male/female ratio increasing with SDB severity. Women with SDB tend to report more morning fatigue but less sleepiness at the wheel and less witnessed sleep apnea than men. Post-menopausal compared to premenopausal women have a higher SDB prevalence not due to an increased BMI but mainly because differences in fat distribution. Funding: Fondation Leenaards, FNS, GSK, Ligue Pulmonnaire Vaudoise and CIRS.