Bone Turnover Markers After Sleep Restriction and Circadian Disruption: A Mechanism for Sleep-Related Bone Loss in Humans.

Bone Turnover Markers After Sleep Restriction and Circadian Disruption: A Mechanism for Sleep-Related Bone Loss in Humans.

J Clin Endocrinol Metab. 2017 Jul 26;:

Authors: Swanson C, Shea SA, Wolfe P, Cain SW, Munch M, Vujovic N, Czeisler CA, Buxton OM, Orwoll ES

Abstract
Context: Sleep abnormalities are associated with low bone mineral density (BMD). Underlying mechanisms are unknown.
Objective: Investigate the impact of sleep restriction with circadian disruption on bone biomarkers.
Hypothesis: Sleep/circadian disruption negatively alters bone turnover.
Design: Intervention Study.
Participants & Methods: Four bone biomarkers (CTX = bone resorption; P1NP = bone formation; sclerostin/FGF-23 = osteocyte function) were measured in bihourly serum samples over 24-h at baseline and after ∼3 weeks of sleep restriction (5.6 h sleep/24-h) with concurrent circadian disruption (recurring 28-h 'day' in dim light) in 10 healthy men (age groups: 20-27yr, n = 6; 55-65yr, n = 4). The effects of sleep/circadian disruption and age on bone biomarker levels were evaluated using maximum likelihood estimation in a mixed model for repeated measures.
Results: P1NP levels were lower post intervention compared to baseline (p< 0.001); the decrease in P1NP was greater for the younger compared to older men (28.0% vs 18.2%, p<0.001). The intervention resulted in no change in CTX (Δ = 0.03 ± 0.02 ng/mL, p = 0.10). Sclerostin levels were higher post-intervention in the younger men only (Δ = 22.9% or 5.64 ± 1.10 pmol/L, p < 0.001).
Conclusions: These data suggest that 3 weeks of circadian disruption with concurrent sleep restriction can lead to an uncoupling of bone turnover wherein bone formation is decreased but bone resorption is unchanged. Circadian disruption and sleep restriction may be most detrimental to bone in early adulthood.

PMID: 28973223 [PubMed - as supplied by publisher]

from # All Medicine by Alexandros G. Sfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2fQlRvV
via IFTTT