Sleep disruption adversely affects bone in men

ORLANDO, Fla. — Circadian disruptions, such as those associated with shift work, may decrease bone formation in young healthy men compared with older men, according to

“This altered bone balance creates a potential bone loss window that could lead to osteoporosis and bone fractures,” Christine Swanson, MD, an assistant professor at the University of Colorado in Aurora, said in a news release. “If chronic sleep disturbance is identified as a new risk factor for osteoporosis, it could help explain why there is no clear cause for osteoporosis in the approximately 50% of the estimated 54 million Americans with low bone mass or osteoporosis.”

Swanson and colleagues evaluated 10 healthy men (aged 20-27 years, n = 6; aged 55-65 years, n = 4) to investigate the impact of combined circadian disruption with sleep loss, akin to the stresses endured during rotating shift work, on biomarkers of bone metabolism.

C-terminal telopeptide (CTX), amino terminal propeptide (PINP), sclerostin and fibroblast growth-factor 23 (FGF23) were measured in plasma samples every 2 hours over 24 hours at baseline and after a 3 week intervention of sleep restriction of 5.6 hours of sleep per 24 hours with concurrent circadian disruption.

Younger participants had higher CTX (P = .02) and PINP (P = .02) compared with older participants whereas older participants had higher sclerostin (P = .005). Compared with baseline, PINP levels were significantly lower after the intervention and the decline was significantly greater in younger participants with higher bone turnover at baseline (P < .001) compared with older participants (P < .001). After the intervention, sclerostin levels were significantly lower in younger participants (P = .002) compared with older participants. FGF23 levels were 6.5% lower after the intervention (P = .01).

“In summary, this study found that 3 weeks of sleep restriction with a history of circadian disruption can lead to an uncoupling of bone turnover and a potential bone loss for catabolic window,” Swanson said during her presentation.

“Furthermore, since the decrease in P1NP was greater for the younger compared to older men, these data suggest that sleep restriction and circadian disruption may be most detrimental to bone health during early adulthood, a critical time for attainment of peak bone mass. Further studies are need to confirm these data and to explore the mechanisms of sex differences.” – by Amber Cox

Reference:

Swanson C, et al. OR08-6. Presented at: The Endocrine Society Annual Meeting; April 1-4, 2017; Orlando, Fla.

Disclosures: Swanson reports no relevant financial disclosures.