Bone Microarchitecture Is Impaired in Adolescent Amenorrheic Athletes Compared with Eumenorrheic Athletes and Nonathletic Controls

• Published in: The journal of clinical endocrinology and metabolism Vol. 96; no. 10; pp. 3123 - 3133
• Main Authors: Ackerman, Kathryn E., Nazem, Taraneh, Chapko, Dorota, Russell, Melissa, Mendes, Nara, Taylor, Alexander P., Bouxsein, Mary L., Misra, Madhusmita
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Oxford University Press 01.10.2011; Copyright by The Endocrine Society; Endocrine Society
• Subjects: Adolescent; Age; Aging - physiology; Amenorrhea - diagnostic imaging; Amenorrhea - pathology; Athletes; Biological and medical sciences; Body Height - physiology; Body Mass Index; Body Weight - physiology; Bone and Bones - anatomy & histology; Bone and Bones - diagnostic imaging; Bone mass; Bone mineral density; Cancellous bone; Computed tomography; Cross-Sectional Studies; Dual energy X-ray absorptiometry; Endocrine Research; Endocrinopathies; Exercise - physiology; Feeding. Feeding behavior; Female; Fractures; Fundamental and applied biological sciences. Psychology; Humans; Immunoassay; Medical sciences; Menstruation - physiology; Radius; Regression Analysis; Tibia; Tibia - anatomy & histology; Tomography, X-Ray Computed; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vertebrates: endocrinology; Vitamin D; Vitamin D - blood; Weight; Young Adult; Human; Obesity; Nutrition; Nutrition disorder; Metabolic diseases; Athlete; Osteoarticular system; Sport; Surveillance; Adolescent; Bone; Endocrinology; Nutritional status; Comparative study
• ISSN: 0021-972X; 1945-7197; 1945-7197
• DOI: 10.1210/jc.2011-1614

Context:Bone mineral density (BMD) is lower in young amenorrheic athletes (AA) compared to eumenorrheic athletes (EA) and nonathletic controls and may contribute to fracture risk during a critical time of bone accrual. Abnormal bone microarchitecture is an independent determinant of fracture risk and has not been assessed in young athletes and nonathletes.Objective:We hypothesized that bone microarchitecture is impaired in AA compared to EA and nonathletes despite weight-bearing exercise.Design and Setting:We conducted this cross-sectional study at the Clinical Research Center of Massachusetts General Hospital.Subjects and Outcome Measures:We assessed BMD and bone microarchitecture in 50 subjects [16 AA, 18 EA, and 16 nonathletes (15–21 yr old)] using dual-energy x-ray absorptiometry and high-resolution peripheral quantitative computed tomography.Results:Groups did not differ for chronological age, bone age, body mass index, or vitamin D levels. Lumbar BMD Z-scores were lower in AA vs. EA and nonathletes; hip and femoral neck BMD Z-scores were highest in EA. At the weight-bearing tibia, athletes had greater total area, trabecular area, and cortical perimeter than nonathletes, whereas cortical area and thickness trended lower in AA. Trabecular number was lower and trabecular separation higher in AA vs. EA and nonathletes. At the non-weight-bearing radius, trabecular density was lower in AA vs. EA and nonathletes. Later menarchal age was an important determinant of impaired microarchitecture. After controlling for covariates, subject grouping accounted for 18–24% of the variability in tibial trabecular number and separation.Conclusion:In addition to low BMD, AA have impaired bone microarchitecture compared with EA and nonathletes. These are the first data to show abnormal bone microarchitecture in AA.