FROM MENOPAUSE
Postmenopausal women without osteoporosis on their first bone mineral density test are unlikely to fracture before age 65, and are therefore unlikely to benefit from regular or repeated screening before that age, according to an analysis of results from a large cohort study.
“Our data can help inform a BMD testing interval for postmenopausal women who are screened before age 65 years. Using the more conservative time estimates for major osteoporotic fracture, clinicians might allow women aged 50 to 54 years without osteoporosis on their first BMD test to wait 10 years for their next test. Similarly, women aged 60 to 64 years without osteoporosis on their first BMD test might wait until after age 65 years for their next test,” Dr. Margaret Lee Gourlay of the University of North Carolina, Chapel Hill, and her associates wrote in their analysis.
Dr. Gourlay and her coinvestigators on the larger Women’s Health Initiative cohort study looked at data from 4,068 postmenopausal women between the ages of 50 and 64 years. None of the women had prior hip or vertebral fractures or received antifracture treatment; they underwent baseline bone mineral density testing between 1993 and 2005. Fracture follow-up continued through 2012 (Menopause 2014 [ doi: 10.1097/gme.0000000000000356 ]).
Among women with a normal BMD on first screening, the estimated time for 1% of those aged 50-54 years to have a hip or clinical vertebral fracture was 12.8 years. Among women aged 60-64 years, the time to fracture was 7.6 years, Dr. Gourlay and her colleagues found.
For the 8.5% of women in the cohort (all ages) with osteoporosis at baseline (n = 344), the age-adjusted time to hip or vertebral fracture was only 3 years.
Dr. Gourlay and her colleagues also estimated times to major osteoporotic fracture for 3% of the cohort, finding that it took 11.5 years for women aged 50-54 years to sustain a hip, clinical vertebral, proximal humerus, or wrist fracture, compared with 8.6 years for women who were 60-64 years at baseline. For women who had osteoporosis at baseline, the age-adjusted time for 3% to have an osteoporotic fracture was 2.5 years.
The researchers acknowledged as limitations of the study the fact that time estimates were based only on transitions to major fracture; that the full benefits and risks of screening, including cost-effectiveness, were not analyzed; and that the study was not powered to determine fracture risk in subgroups defined by individual risk factors.
Nonetheless, the results suggest that deferred repeat screening can be safe for postmenopausal women aged 50 years and older with normal BMD results at baseline, Dr. Gourlay and her coauthors wrote.
The study was funded by the National Institutes of Health. One of Dr. Gourlay’s coauthors is a consultant for MSD, and another reported receiving recent funding from Bone Ultrasound Finland.
