Summary
Sowers MR, Zheng H, Greendale GA, et al. Changes in bone resorption across the menopause transition: effects of reproductive hormones, body size, and ethnicity. J Clin Endocrinol Metab. 2013;98(7):2854-2863. Level of evidence: II-3.
Researchers examined how changes in bone resorption relate to the final menstrual period (FMP), reproductive hormones, body mass index (BMI), and ethnicity by measuring urinary type 1 collagen N-telopeptide (NTX), estradiol, and follicle-stimulating hormone levels annually for up to 8 years of the menopause transition in 918 women (classified as African American, Chinese, Japanese, or Caucasian). They found that urinary NTX began to increase sharply about 2 years before the FMP, peaking about 1 to 1.5 years after the FMP. From 2 to 6 years after the FMP, NTX levels declined but stayed about 20% higher than before menopause.
The magnitude of the increase in bone resorption was inversely associated with BMI. Ethnic differences in bone resorption changes were weakened but not wholly eliminated by adjusting for BMI. Thus, ethnic differences in BMI appear to account for much of the ethnic variation in bone loss during perimenopause.