Prevalence and risk factors of vertebral compression fractures in female SLE patients
1 Department of Rheumatology and Inflammation Research, Sahlgrenska Academy at University of Gothenburg, Guldhedsgatan 10A, S-413 46 Göteborg, Sweden
2 Department of Radiology, Sahlgrenska University Hospital, Sweden
3 Current address: European Telemedicine Clinic, Torre Mapfre C/Marina 16-18, 08005 Barcelona, Spain
4 Department of Internal Medicine, Sahlgrenska Academy at University of Gothenburg, Grönastråket 8, S-413 45 Göteborg, Sweden
Arthritis Research & Therapy 2010, 12:R153 doi:10.1186/ar3104Published: 2 August 2010
Our objective was to determine the frequency of and factors associated with prevalent vertebral compression fractures in female systemic lupus erythematosus (SLE) patients attending rheumatologists in western Sweden.
In this cross sectional study 150 women were included. They were examined with x-ray of thoracic and lumbar spine (Th4 to L4). A reduction of at least 20% of any vertebral height, assessed by Genant's semiquantitative method, was defined as a fracture. Bone mineral density (BMD) was measured by dual energy x-ray absorptiometry (DXA).
Median patient age was 47 years (20 to 82) and disease duration 11 years (1 to 41). Only 6 (4%) women had a history of clinical compressions whereas 43 (29%) had at least one radiological fracture each. The patients with at least one fracture at any site were characterized by older age (P < 0.001), being postmenopausal (P < 0.01), higher Systemic Lupus International Collaborative Clinics Damage Index (P < 0.05), lower BMD total hip and femoral neck (P < 0.05), more peripheral fractures (P < 0.01), medication with bisphosphonates (P <0.05) and calcium and vitamin D3 (P < 0.05). There were no significant differences regarding current or cumulative glucocorticosteroid dose between the groups. In logistic regression analyses high age remained as a risk factor of at least one vertebral fracture at any site whereas low BMD in total hip was associated with vertebral fracture in the lumbar spine.
Radiological compression fractures are common but seldom diagnosed in SLE patients. High age and low BMD in total hip, but not in spine, was associated with vertebral fractures.