Low bone density risk is higher in exercising women with multiple triad risk factors

Med Sci Sports Exerc. 2014 Jan;46(1):167-76. doi: 10.1249/MSS.0b013e3182a03b8b.

Abstract

The cumulative effect of the female athlete triad (Triad) risk factors on the likelihood of low bone mineral density (BMD) in exercising women is unclear.

Purpose: This study aimed to determine the risk of low BMD in exercising women with multiple Triad risk factors.

Methods: We retrospectively examined cross-sectional data from 437 exercising women (mean ± SD age of 18.0 ± 3.5 yr, weighed 57.5 ± 7.1 kg with 24.5% ± 6.1% body fat) obtained at baseline from 4 prospective cohort studies examining Triad risk factors. Questionnaires were completed to obtain information on demographic characteristics, self-reported eating attitudes/behaviors, menstrual function, sport/activity participation, and medication use. Height and body weight were measured. BMD was measured using dual energy x-ray absorptiometry. Low BMD was defined as z-scores of <-1 and ≤-2. Chi-square tests were performed to determine the percentage of women with low BMD who met the criteria for individual (current oligo/amenorrhea, late menarche, low body mass index (BMI), elevated dietary restraint, lean sport/activity participation) or multiple (2, 3, 4, or 5) Triad risk factors.

Results: Late menarche and low BMI were associated with the highest percentage of low BMD (z-score < -1), 55% and 54%, respectively, and low BMD (z-score ≤-2), 14% and 16%, respectively. The percentage of participants with low BMD (z-score < -1 and ≤-2) increased from 10% to 62% and from 2% to 18%, respectively, as women met the criteria for an increasing number of Triad risk factors.

Conclusions: A cumulative number of Triad risk factors were associated with an increased risk of low BMD, suggesting a dose-response association between the number of Triad risk factors and BMD in exercising women. Further research should be conducted to develop a user-friendly algorithm integrating these indicators of risk for low BMD in exercising women (particularly factors associated with low BMI/body weight, menstrual dysfunction, lean sport/activity participation, and elevated dietary restraint).

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Age Factors
  • Amenorrhea / physiopathology
  • Body Mass Index
  • Bone Density / physiology*
  • Caloric Restriction
  • Cross-Sectional Studies
  • Energy Intake / physiology
  • Exercise / physiology*
  • Female
  • Humans
  • Menarche
  • Oligomenorrhea / physiopathology
  • Retrospective Studies
  • Risk Factors
  • Sports / physiology
  • Young Adult