Patterns of Bone Mineral Density Loss at Multiple Skeletal Sites Following Recent Menopause in Users and Non-Users of Menopausal Hormone Therapy.

Abstract

Post-menopausal bone loss has been well described, however fewer studies have focussed on changes around the time of menopause. This study describes bone mineral density (BMD) loss following recent menopause, stratified by hormone replacement therapy (HT) use. Women (n = 287) who self-reported recent menopause (≥ 12 months to < 5 yr since last menstrual period) for at least one assessment phase of the Geelong Osteoporosis Study were included. BMD was measured using Lunar DPX-L and GE-Prodigy machines. Time since menopause was calculated for each participant at each assessment phase and divided into three categories: < 5 yr, 5-10 yr and ≥ 10 yr. BMD loss was expressed as: (i) cumulative loss over time, (ii) absolute value per year and (iii) percentage loss per year. Proportions of women with normal BMD, osteopenia and osteoporosis were also calculated. Cumulative BMD loss was lower among HT users than non-users at all sites and time categories, except the femoral neck. Compared to the other time categories, HT non-users had a greater rate of BMD loss (expressed as an absolute value or percentage per year) during the first five years postmenopause at the ultra-distal forearm and lumbar spine. No differences were observed between the time categories for HT users. The proportions of women with osteopenia and osteoporosis increased across each of the time categories, but patterns differed by skeletal site, being more pronounced for the femoral neck and mid-forearm sites. Rates of bone loss were greater at the lumbar spine and ultra-distal forearm during the first five years following menopause.