Hongting Ning1, Yan Du2, Lan-Juan Zhao3, Qing Tian3, Hui Feng4, Hong-Wen Deng5. 1. Xiangya School of Nursing, Central South University, Changsha, Hunan, China. 2. School of Nursing, University of Texas Health Science Center at San Antonio, San Antonio, TX. 3. Department of Biostatistics, Center for Bioinformatics and Genomics, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA. 4. Xiangya School of Nursing, Xiangya-Oceanwide Health Management Research Institute, Central South University, Changsha, Hunan, China. 5. School of Medicine, Tulane University, New Orleans, LA.
Abstract
OBJECTIVE: To examine the contribution of skeletal mass index (SMI) as a mediator in the relationship between menarcheal age and hip/spine bone mineral density (BMD) in premenopausal women by race/ethnicity. METHODS: The data of 4,329 participants (age ≥ 18; mean age=35.7 ± 9.5) of Whites (n = 2,543), African Americans (n = 1,236), and Asians (n = 550) enrolled from October 2011 to January 2019 from the Louisiana Osteoporosis Study were analyzed. After adjustment for physiological and behavioral factors, multivariable linear regression analyses were conducted to evaluate each component of the proposed mediation models, and mediation was verified by the bootstrapping resampling approach. RESULTS: Premenopausal women with early menarcheal age tended to have higher SMI and BMD than women with normal menarcheal age among all races/ethnicities included. Women with late menarcheal age were, however, more likely to have a lower SMI than their counterparts with normal menarcheal age (r = -0.212, 95% CI = [-0.321 to -0.103] for White women; r = -0.181, 95% CI = [-0.410 to -0.008] for African-American women; r = -0.174, 95% CI = [-0.343 to -0.006] for Asian women). Similar results were found for both spine and hip BMD. SMI fully mediated the difference in BMD due to different menarcheal ages among Whites, African Americans, and Asian women with early menarcheal age; however, no mediating effects were observed for Asian women with late menarcheal age. CONCLUSIONS: SMI, as a full mediator, affected the relationship between menarcheal age and BMD among premenopausal women, and the mediating effects varied by race/ethnicity. To prevent or slow down the loss of hip/spine BMD and the development of osteoporosis, measures aiming at minimizing the risk for muscle mass loss should be recommended, especially for White and African-American women with late menarcheal age.
OBJECTIVE: To examine the contribution of skeletal mass index (SMI) as a mediator in the relationship between menarcheal age and hip/spine bone mineral density (BMD) in premenopausal women by race/ethnicity. METHODS: The data of 4,329 participants (age ≥ 18; mean age=35.7 ± 9.5) of Whites (n = 2,543), African Americans (n = 1,236), and Asians (n = 550) enrolled from October 2011 to January 2019 from the Louisiana Osteoporosis Study were analyzed. After adjustment for physiological and behavioral factors, multivariable linear regression analyses were conducted to evaluate each component of the proposed mediation models, and mediation was verified by the bootstrapping resampling approach. RESULTS: Premenopausal women with early menarcheal age tended to have higher SMI and BMD than women with normal menarcheal age among all races/ethnicities included. Women with late menarcheal age were, however, more likely to have a lower SMI than their counterparts with normal menarcheal age (r = -0.212, 95% CI = [-0.321 to -0.103] for White women; r = -0.181, 95% CI = [-0.410 to -0.008] for African-American women; r = -0.174, 95% CI = [-0.343 to -0.006] for Asian women). Similar results were found for both spine and hip BMD. SMI fully mediated the difference in BMD due to different menarcheal ages among Whites, African Americans, and Asian women with early menarcheal age; however, no mediating effects were observed for Asian women with late menarcheal age. CONCLUSIONS: SMI, as a full mediator, affected the relationship between menarcheal age and BMD among premenopausal women, and the mediating effects varied by race/ethnicity. To prevent or slow down the loss of hip/spine BMD and the development of osteoporosis, measures aiming at minimizing the risk for muscle mass loss should be recommended, especially for White and African-American women with late menarcheal age.
Authors: Gail A Greendale; MaryFran Sowers; Weijuan Han; Mei-Hua Huang; Joel S Finkelstein; Carolyn J Crandall; Jennifer S Lee; Arun S Karlamangla Journal: J Bone Miner Res Date: 2012-01 Impact factor: 6.741
Authors: Susana Bubach; Ana Maria Baptista Menezes; Fernando Celso Barros; Fernando César Wehrmeister; Helen Gonçalves; Maria Cecília Formoso Assunção; Bernardo Lessa Horta Journal: BMC Public Health Date: 2016-09-22 Impact factor: 3.295