71605
document
Melatonin improves bone mineral density at the femoral neck in postmenopausal women with osteopenia : a randomized controlled trial . Melatonin is known for its regulation of circadian rhythm . Recently , studies have shown that melatonin may have a positive effect on the skeleton . By increasing age , the melatonin levels decrease , which may lead to a further imbalanced bone remodeling . We aimed to investigate whether treatment with melatonin could improve bone mass and integrity in humans . In a double-blind RCT , we randomized 81 postmenopausal osteopenic women to 1-yr nightly treatment with melatonin 1 mg ( N = 20 ) , 3 mg ( N = 20 ) , or placebo ( N = 41 ) . At baseline and after 1-yr treatment , we measured bone mineral density ( BMD ) by dual X-ray absorptiometry , quantitative computed tomography ( QCT ) , and high-resolution peripheral QCT ( HR-pQCT ) and determined calciotropic hormones and bone markers . Mean age of the study subjects was 63 ( range 56-73 ) yr . Compared to placebo , femoral neck BMD increased by 1.4 % in response to melatonin ( P < 0.05 ) in a dose-dependent manner ( P < 0.01 ) , as BMD increased by 0.5 % in the 1 mg/day group ( P = 0.55 ) and by 2.3 % ( P < 0.01 ) in the 3 mg/day group . In the melatonin group , trabecular thickness in tibia increased by 2.2 % ( P = 0.04 ) , and volumetric bone mineral density ( vBMD ) in the spine , by 3.6 % ( P = 0.04 ) in the 3 mg/day . Treatment did not significantly affect BMD at other sites or levels of bone turnover markers ; however , 24-hr urinary calcium was decreased in response to melatonin by 12.2 % ( P = 0.02 ) . In conclusion , 1-yr treatment with melatonin increased BMD at femoral neck in a dose-dependent manner , while high-dose melatonin increased vBMD in the spine . Further studies are needed to assess the mechanisms of action and whether the positive effect of nighttime melatonin will protect against fractures .
71606
Intervention_Pharmacological
Melatonin
71607
Intervention_Pharmacological
Melatonin
71608
Intervention_Pharmacological
melatonin
71609
Intervention_Pharmacological
melatonin
71610
Intervention_Pharmacological
melatonin
71611
Intervention_Control
placebo
71612
Intervention_Physical
dual X-ray absorptiometry
71613
Intervention_Physical
quantitative computed tomography
71614
Intervention_Physical
high-resolution peripheral QCT
71615
Intervention_Control
placebo
71616
Intervention_Pharmacological
melatonin
71617
Intervention_Pharmacological
melatonin
71618
Intervention_Pharmacological
melatonin
71619
Outcome_Physical
femoral neck BMD
71620
Outcome_Physical
BMD
71621
Outcome_Physical
trabecular thickness in tibia
71622
Outcome_Physical
volumetric bone mineral density ( vBMD )
71623
Outcome_Physical
spine
71624
Outcome_Physical
BMD
71625
Outcome_Physical
levels of bone turnover markers ;
71626
Outcome_Physical
24-hr urinary calcium
71627
Outcome_Physical
BMD at femoral neck
71628
Outcome_Physical
vBMD
71629
Outcome_Physical
spine
71630
Participant_Condition
postmenopausal
71631
Participant_Sex
women
71632
Participant_Condition
osteopenia
71633
Participant_Sample-size
81
71634
Participant_Condition
postmenopausal osteopenic
71635
Participant_Sex
women
71636
Participant_Condition
treatment with melatonin 1 mg ( N = 20 ) , 3 mg ( N = 20 ) , or placebo ( N = 41 )
71637
Participant_Age
Mean age of the study subjects was 63 ( range 56-73 ) yr