Radiological Lumbar Lesions Highly Prevalent in Patients with Rheumatoid Arthritis

Spondylolisthesis and vertebral fracture were significantly more prevalent in patients with rheumatoid arthritis (RA) than in the general population, according to study findings published in the Spine Journal.

Investigators extracted data from a 10-year prospective cohort study of patients with RA and age- and sex-matched controls. The study was conducted at the Osaka City University Medical School in Japan. Patients were recruited from the associated clinic; healthy controls were recruited from the local population. Disease activity was measured at baseline using the 28-joint Disease Activity Score with C – reactive protein (DAS28-CRP). Low back pain was assessed by patient report using a Visual Analogue Scale. Lumbar spondylolisthesis and prevalent vertebral fracture were evaluated on plain lateral X-ray in both patients and controls. Bone mineral density was assessed by dual-energy X-ray absorptiometry. Thoraco-lumbar scoliosis was determined by whole-body dual-energy X-ray absorptiometry. The prevalence rates of lumbar spondylolisthesis and vertebral fractures were compared between patients and controls. Logistic regression was conducted to assess the relationship between RA and lumbar lesions.  

In total, data was collected from 185 patients and 188 controls. The mean age was 58.4 ± 12.5 and 57.8 ± 12.4 years in the patient and control groups, respectively. Lower back pain scores were not significantly different between patients and controls. Compared with the control group, the RA group had significantly higher prevalence rates of spondylolisthesis (26.6% vs 46.5%; P <.01) and prevalent vertebral fracture (33.9% vs 35.9%; P =.01). Patients with RA also had a nominally higher prevalence of thoraco-lumbar scoliosis (29.7% vs 22.9%; P =.08). In multivariate analyses, a diagnosis of RA was associated with significantly higher odds of vertebral fracture (adjusted odds ratio [OR], 1.670; 95% confidence interval [CI], 1.062-2.628) and spondylolisthesis (OR, 2.669; 1.661-4.289). Men were less likely than women to have vertebral fracture (OR, 0.510; 95% CI, 0.265-0.979). Greater lumbar bone mineral density was associated with lower odds of vertebral fracture (OR, 0.243; 95% CI, 0.070-0.845). In the total cohort, lower back pain was associated with older age. In the RA cohort, both age and DAS28-CRP score correlated with lower back pain.

Limitations of the study include prevalence of vertebral fracture in the control group being higher than those previously reported and there may have been some other selection bias in the control subjects. Additionally, the prevalence and risk factors related to lumbar lesion were analyzed in patients with RA; however, the characteristics of lumbar lesion were not analyzed.

Compared to the general population, patients with RA were more likely to present with radiological lumbar lesions. Lower back pain was associated with disease activity, suggesting that disease management may improve lumbar symptoms in this population.  

Reference

Suzuki A, Tamai K, Takahashi S, et al. Do rheumatoid arthritis patients have low back pain or radiological lumbar lesions more frequently than the healthy population? – Cross-sectional analysis in a cohort study with age and sex-matched healthy volunteers. Spine J. Published online July 2, 2020. doi: 10.1016/j.spinee.2020.06.020