Associations between sleep and breathing with sarcopenia in postmenopausal women.
Background
Post-menopausal women are at increased risk of sleep disturbance and sarcopenia [1, 2]. Emerging evidence indicates that reduced muscle mass and muscle strength may be influenced by disturbed sleep via a complex interplay of hormonal, metabolic and inflammatory pathways alongside a lack of physical activity [3]. We aimed to investigate the cross-sectional associations between sleep and breathing with sarcopenia in postmenopausal women.
Methods:
The study focused on female participants [median age (interquartile range): 59 (54-67) years, N=389] from the 1st follow-up of the Colaus study [4, 5]who underwent polysomnography (PSG) examinations and dual-energy X-ray absorptiometry (DXA). Sarcopenia was defined according to the Foundation for the National Institutes of Health criteria: low muscle mass and low muscle strength [6]. Appendicular skeletal muscle mass adjusted for body mass index (ASMI) was used as a measure of muscle mass, and handgrip strength was used as a measure of muscle strength. Participants were categorised as having sarcopenia when their ASMI and handgrip strength both fell within the lowest tertile of the sample distribution (cut off values 0.64 and 22.38kg respectively). Indicators of sleep disturbance were defined as short sleep duration (<6 hours), poor sleep efficiency (<80%), prolonged sleep onset latency (>30 minutes), time in slow wave sleep and rapid eye movement sleep below median, prolonged wake after sleep onset (WASO) (awake for >30 minutes), and obstructive sleep apnoea (OSA) severity as indicated by apnoea hypopnea index (AHI) (number of events /hour) and nocturnal hypoxemia (>1% of sleep time with oxygen saturation below 90%). Confounders tested for inclusion were age, smoking, alcohol consumption, weekly energy consumption and comorbidities. Binomial logistic regression models analyzed associations between sleep and breathing with sarcopenia.
Results:
Sarcopenia was detected in 61(15.7%) of the participants. After adjustment for potential confounders, short sleep duration (Odds ratio [OR]=1.10, 95% Confidence interval [CI] = 1.01-1.21), prolonged WASO (OR=1.09, 95% CI= 1.01-1.17), severe OSA (AHI> 30) (OR=1.21, 95% CI= 1.06-1.38) and nocturnal hypoxemia (OR=1.09, 95% CI= 1.01-1.19) were significantly associated with sarcopenia.
Conclusion:
Postmenopausal women experiencing sleep and breathing disturbance including short sleep duration, increased night-time wakefulness and severe OSA are more likely to have sarcopenia. The potential pathophysiological links between sleep disturbance and sarcopenia create future opportunities to develop interventions and public policies to reduce the burden derived from age-related conditions.