Prevalence of vertebral fractures among patients with chronic obstructive pulmonary disease in Canada

Purpose: Patients with chronic obstructive pulmonary disease (COPD) may be at higher risk for osteoporosis. The primary objective of this case-control study was to determine the prevalence of vertebral fractures among patients with COPD admitted to acute care compared with a gender- and age-matched control group. Subjects and methods: Subjects were identified by chart reviews from an acute care hospital in Hamilton, Ontario, in 1999, including patients who were over 50 years old. In total, 127 patients with ICD-9 codes specifying COPD were randomly selected and compared with 127 gender- and age-matched controls. Chest radiographs were interpreted by two radiologists who defined and graded vertebral fractures using Genant's method. Medications taken, or prescribed at discharge, were recorded from charts. Results: The overall prevalence of at least one vertebral fracture was found to be 34/127 (26.8%) in the COPD patients compared with 30/127 (23.6%) in the controls (p=0.556). A significantly greater proportion of COPD patients had at least one severe vertebral fracture (OR=3.75, 95% CI 1.24 to 11.3). Review of hospital chest X-ray reports indicated that only 12 of 64 (18.8%) patients with vertebral fractures identified by the study radiologists actually had a vertebral fracture noted in the report. The proportion of COPD patients with vertebral fractures who were discharged on osteoporosis therapy was 5/27 (18.5%). There was a suggestion of lower lung function, as measured by forced vital capacity (FVC%), in patients with severe vertebral fractures (p=0.067). Conclusions: These data indicate that: (1) There is an increased proportion of COPD patients with severe vertebral fracture, and (2) Documentation and treatment of osteoporosis in acute care COPD patients is low. Therefore, there is a need to target this high-risk group for osteoporosis screening and potential clinical management.