Is there any clinical benefit to a repeat bone mineral density screening test after an initial baseline screen in elderly men and women?
This study found little, if any, added benefit to repeat bone mineral density (BMD) screening at 4 years beyond baseline BMD testing in elderly men and women. A recent similar study (Gourlay ML, et al. NEJM 2012;366(3):225-33) recommended a baseline examination at age 65 with repeat testing necessary only after 15 years in patients with mild osteopenia and after 5 years in patients with moderate osteopenia. It looks like we should be doing a lot fewer DEXA scans than we’ve been doing. (LOE = 1b)
Berry SD, Samelson EJ, Pencina MJ, et al. Repeat bone mineral density screening and prediction of hip and major osteoporotic fracture. JAMA 2013;310(12):1256-1262.
Study design: Cohort (prospective)
Funding source: Government
These investigators analyzed data obtained from consenting adult participants of the ongoing Framingham cohort invited to have 3 BMD tests each about 4 years apart starting in 1987. Study participants (310 men and 492 women; mean age = 74.8 years) included those who had at least 2 BMD measures with a mean time between each of 3.7 years. Follow-up occurred for participants until death or through 2009 or 12 years after the second BMD. Individuals assessing medical records confirmed self-reported hip fractures, but no other major osteoporotic fractures, including spine, forearm, or shoulder. During a mean follow-up of 9.6 years, 1 or more major osteoporotic fracture occurred in 113 (14%) patients. Prediction modeling for hip or major osteoporotic fracture based on baseline BMD performed much better than models based on BMD change. Furthermore, adding BMD change as a variable to models using baseline BMD did not significantly improve prediction performance. Overall, the net change in the percentage of patients with a hip fracture reclassified with a second BMD as being at high risk was not significant (3.9%; 95% CI, -2.2% to 9.9%). Likewise, the net change in the percentage of patients without hip fracture reclassified as low risk by a second BMD was also not significant (-2.2%; 95% CI, -4.5% to 0.1%).
David Slawson, MD
Vice Chair, Department of Family Medicine
University of Virginia