A population-based study of osteoporosis testing and treatment following introduction of a new bone densitometry service.

Bone density measurement plays a key role in the initial diagnostic assessment of osteoporosis and in targeting pharmacologic therapies. The impact of access to dual-energy X-ray absorptiometry (DXA) on physician prescribing habits is unclear, however. We were able to directly evaluate the change in physician osteoporosis testing and prescribing following introduction of a DXA testing service in a geographic region that had previously had very limited access. This evaluation was conducted in the province of Manitoba, Canada, which has a provincially based bone density testing program and maintains a population-based bone density database that can be linked with administrative health data sources including drug prescriptions. The province of Manitoba was geographically partitioned into the urban and rural health regions serviced by the new program (urban(new )and rural(new)) and the remaining urban and rural health regions which had relatively unchanged DXA access during this period (urban(control) and rural(control)). Regression models of DXA testing rates and osteoporosis prescription rates were created for all older women in these regions. There was a statistically significant increase in bone density testing and BMD-guided osteoporosis treatment in the urban(new) and rural(new) regions following introduction of the DXA testing service, relative to the control regions. Although the overall rate of empiric postfracture and preventive osteoporosis treatment did not show a specific region effect, when analysis was limited to nonhormonal agents there was a significant reduction in preventive and empiric postfracture treatment in some subgroups of women. These results suggest that the local availability of the bone density testing service led to an increase in objective test-guided therapy with some reduction in the use of empiric and preventive strategies and had a neutral effect on overall use of these agents.