Clinical Trial: Effects of Anorexia Nervosa on Bone Mass in Adolescents

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Effects of Anorexia Nervosa on Peak Bone Mass

Brief Summary: This study is to determine the effects of anorexia nervosa on bone mass and hormone levels in adolescents. Whether administration of estrogen, a normal hormone present during puberty, can help maintain bone development in girls with anorexia nervosa will be determined.

Detailed Summary:

Adolescence is a critical time for bone mineral accretion as between 60-90% of peak bone mass is established during this period, and peak bone mass is a major determinant of bone density and osteoporosis risk during adulthood. Anorexia nervosa (AN) is the third most common chronic illness among adolescent girls, with a prevalence of 0.2-1.0%. Therefore, AN occurs at a time during which patients are the most vulnerable to disruption of bone mineral accretion. Osteopenia is a major co-morbid complication of AN in 50-75% of female adolescents and adult women with this eating disorder. Women with the onset of the disorder during adolescence have more severe osteopenia than women with onset during adulthood. Little is known about the pathogenesis of osteopenia in this adolescent population and there are no established therapies. Improved understanding of bone mineral metabolism and factors which predict recovery of bone mineral accretion are critical in the development of therapeutic strategies to preserve and maximize bone mass in girls with the onset of AN during adolescence. Estrogen is known to be a critical factor in the development of peak bone mass. Although AN is associated with profound estrogen deficiency, there are no controlled studies investigating the effects of estrogen administration in this population.

This research proposal will address critical unanswered questions regarding bone abnormalities in adolescents with anorexia nervosa. Defining changes in bone formation with weight recuperation and hormonal variables would provide insight into the factors essential for bone mineral accretion during adolescence, as well as those that predict recovery. Determination of dose-dependent estrogen effects in this population will be key in targeting interventions during the time of active disease, with the long-term goal of preserving peak bone mass accretion in this vul
Sponsor: Massachusetts General Hospital

Current Primary Outcome:

• Percent Change in Spine Bone Density Over the Study Duration (18 Months) [ Time Frame: Baseline and 18 months ]

  Bone density at the spine (lumbar 1-4 vertebrae) was measured using dual energy x-ray absorptiometry (DXA) at baseline, 6 months, 12 months and 18 months.

  The primary outcome was the percent change in bone density at the spine from baseline to 18 months. Areal bone density is measured as g/cm2. The unit of measure for the percent change in bone density is 'percent' Percent change in bone density= [[Bone density at 18 months- Bone density at baseline)*100/Bone density at baseline]%

• Change in Spine Bone Mineral Density Z-scores Over the Study Duration (18 Months) [ Time Frame: Baseline and 18 months ]

  Bone density at the spine (lumbar 1-4 vertebrae) was measured using dual energy x-ray absorptiometry (DXA) at baseline, 6 months, 12 months and 18 months.

  The other primary outcome was the change in spine bone density Z-score from baseline to 18 months. The bone density Z-score is a standard deviation score that compares one's bone density to the mean for age and gender, and the Z-score, therefore, does not have any units. It is simply referred to as a Z-score. Change in bone density Z-score= [Bone density Z-score at 18 months- Bone density Z-score at baseline]

Original Primary Outcome:

Current Secondary Outcome: Change in N-terminal Propeptide of Type 1 Procollagen (P1NP) Over the Study Duration (18 Months) [ Time Frame: Baseline and 18 months ]

Original Secondary Outcome:

Information By: Massachusetts General Hospital

Dates:
Date Received: July 20, 2004
Date Started: July 2003
Date Completion:
Last Updated: October 6, 2011
Last Verified: September 2011