Article

The effects of adiponectin and leptin on changes in bone mineral density.

Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA.
Osteoporosis International (impact factor: 4.58). 08/2011; 23(6):1699-710. DOI:10.1007/s00198-011-1768-x
Source: PubMed

ABSTRACT We tested the hypothesis that low leptin and high adiponectin levels are associated with higher rates of bone mineral density (BMD) loss among 3,075 men and women, aged 70-79, from the Health Aging and Body Composition Study. Results suggest that adiponectin, but not leptin, is a risk factor for bone loss in women.
Adiponectin and leptin are hormones secreted by adipose cells that may impact BMD. Few studies have evaluated the longitudinal association of leptin and adiponectin levels with rates of BMD change.
Hip and whole-body areal BMD (aBMD) were measured five times using dual-energy X-ray absorptiometry over 10 years (average follow-up time, 7.95 ± 1.92 years). Trabecular lumbar spine volumetric BMD (vBMD) was measured using quantitative computed topography at baseline and year 6 in the Pittsburgh cohort only. Random slope and intercept models were used to account for within person correlation as a result of repeated measures of hip and whole-body aBMD. Linear regression was used to model changes in spine trabecular vBMD.
Among women, the annualized rate of hip aBMD loss in the highest tertile of adiponectin was -0.67% (95% CI -0.77, -0.58) compared to [-0.43% (95% CI -0.51, -0.35)] in the lowest tertile (p trend = 0.019) after adjusting for age, race, BMI, diabetes, baseline hip aBMD, and weight change. In men, hip aBMD loss was greatest in the high adiponectin group (tertile 3), however this association was not significant (p trend = 0.148). After adjusting for weight change in women, the association between higher leptin and lower hip aBMD loss was attenuated and no longer significant (p trend = 0.134). Leptin and adiponectin levels were not associated with whole-body aBMD or trabecular lumbar spine vBMD loss.
Adiponectin was associated with increased hip aBMD loss in women only, supporting evidence that adiponectin may have an important role in bone health.

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Keywords

adiponectin levels
 
adipose cells
 
average follow-up time
 
baseline hip aBMD
 
BMD change
 
Body Composition Study
 
bone health
 
dual-energy X-ray absorptiometry
 
hip aBMD loss
 
longitudinal association
 
lower hip aBMD loss
 
lowest tertile
 
model changes
 
Random slope
 
spine trabecular vBMD
 
trabecular lumbar spine vBMD loss
 
Trabecular lumbar spine volumetric BMD
 
weight change
 
whole-body aBMD
 
whole-body areal BMD