An Update on Triad Prevalence and Exploratory Hormonal Biomarker Analyses in Ultramarathon Runners

Abstract

Objective: To update the prevalence of male and female athlete Triad risk factors in ultramarathon runners and present exploratory analyses examining correlations between bone mineral density (BMD) and hormones. Design: Multiyear cross-sectional study. Setting: Western States Endurance Run 100-mile race. Participants: Participants were recruited in 2018 and 2019 for our prior cohort. We added an additional cohort in 2021. Assessment of Risk Factors: Participants completed laboratory evaluations of sex hormones, vitamin D, and ferritin (2019 and 2021 cohorts only); dual energy x-ray absorptiometry; and surveys evaluating nutritional habits, menstrual history, and injury history. Main Outcome Measures: The Triad cumulative risk assessment was assessed for each participant. Results: One hundred seventy-nine runners participated (123 men and 56 women). 61.1% of women and 28.1% of men were at moderate or high cumulative risk for the Triad. In women, there were significant correlations between hip and femoral neck BMD and total testosterone (Spearman correlation coefficient r = 0.58, P = 0.001; r = 0.45, P = 0.01). In men, there were weak, significant correlations (r = 0.24-0.30, P = 0.01–0.04) between estradiol and vitamin D at most anatomic sites. Conclusions: Our results build on our prior CJSM publication. With the addition of about 50% more study participants in 2021, we observed a stable, high prevalence of Triad risk factors, which represents a more precise measurement and highlights the need for future Triad research in the ultramarathon population. We found significant exploratory associations between hormones and BMD, which varied considerably from our prior publication and should be interpreted cautiously.