Incidence and risk factors for osteoporotic fractures in patients with systemic lupus erythematosus versus matched controls

• Main Authors: Chang Seong Kim, Kyung-Do Han, Jin Hyung Jung, Hong Sang Choi, Eun Hui Bae, Seong Kwon Ma, Soo Wan Kim
• Format: Article
• Language: English
• Published: The Korean Association of Internal Medicine 2021-01-01
• Series: The Korean Journal of Internal Medicine
• Subjects: osteoporosis; fracture; lupus erythematosus, systemic; risk
• Online Access: http://www.kjim.org/upload/pdf/kjim-2018-378.pdf

Background/Aims Despite recent improvements in the quality of life of patients with systemic lupus erythematosus (SLE), osteoporosis, and osteoporotic fractures are one of the major complications of SLE. Furthermore, limited data are available on the incidence and predictor of osteoporotic fractures in Korean patients with SLE. Herein, we aimed to assess the incidence and risk factors for osteoporotic fractures in Korean SLE patients compared to those without SLE. Methods SLE patients aged ≥ 40 years (n = 10,434; mean age, 51.3 ± 9.1 years; women, 89.7%) were selected from the Korean National Health Insurance Service database, spanning a period from 2008 to 2014. Age- and sex-matched controls (n = 52,170) were randomly sampled in a 5:1 ratio from non-SLE individuals. The primary outcome was the first occurrence of osteoporotic fracture. Results The incidence of osteoporotic fractures was significantly higher in the SLE patients (19.085 per 1,000 person-years) than in matched controls (6.530 per 1,000 person-years). According to the multivariable Cox proportional analysis, patients with SLE exhibited a higher osteoporotic fracture rate than the control group (hazards ratio, 2.964; 95% confidence interval, 2.754 to 3.188), even after adjustment for confounding variables. In the subgroup analysis, male SLE patients or SLE patients aged 40 to 65 years were associated with a higher osteoporotic fracture rate than women SLE patients or SLE patients aged ≥ 65 years, respectively. Conclusions We found a 2.964-fold increased risk of osteoporotic fracture in SLE patients compared to age- and sex-matched non-SLE controls. Male or middle-aged SLE patients had a relatively higher fracture risk among patients with SLE.