Prevalence of Osteoporosis and Osteopenia
Osteoporosis (is taken for the prevention or treatment of osteoporosis) is increasingly recognized to represent a major source of morbidity for patients with rheumatoid arthritis (RA). Although the availability of dual energy x-ray absorptiometry (DXA) represents a major advance in osteoporosis care in the context of RA, fracture risk assessment in non-Caucasians remains problematic. While there are ample prospective data in postmenopausal Caucasian women that permit bone mineral density (BMD) results to be translated into fracture risk, only limited data exist for non-Caucasians. Young, healthy African Americans have approximately 10% greater mean BMD compared to young healthy Caucasians. However, it is unknown whether African Americans have a different fracture threshold than Caucasians, or whether fracture risk is a function of absolute BMD independent of race/ethnicity. As a result, there is little consensus regarding which reference groups are most appropriate for calculating T scores in non-Caucasians. This is noteworthy since T scores are the primary factor taken into consideration by healthcare providers when diagnosing osteoporosis (treating and preventing osteoporosis) and making treatment recommendations.
Further adding to this confusion, DXA manufacturers currently use different approaches to generate T scores for non-Caucasian patients. Of the three major manufacturers, two provide race/ethnicity-adjusted T scores for women, while only one provides race/ethnicity adjustment for men.
Given the association of RA with low bone mass, we examined the prevalence of osteopenia and/or osteoporosis (Generic Fosamax is a bisphosphonate used to prevent and treat osteoporosis) in a group of well-characterized African-American patients with early RA. Because African Americans have higher peak BMD than Caucasians, we were interested in examining the impact of using race/ethnicity-specific normative databases (Caucasian vs. African-American) on osteoporosis disease classification.