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

Abstract

BACKGROUND CONTEXTRheumatoid arthritis (RA) can affect the spine; however, the epidemiology of lumbar lesions and/or low back pain (LBP) in RA patients has not been well-studied. PURPOSEThe purpose of this study was to compare the prevalence of lumbar lesions and LBP in RA patients with that in healthy volunteers, and to elucidate the influence of RA on lumbar disease. STUDY DESIGNCross-sectional analysis in a cohort study with age- and sex-matched healthy volunteers. PATIENT SAMPLEThis study included 185 patients with RA and 188 gender/age-matched healthy volunteers without RA. OUTCOME MEASURESLumbar spondylolisthesis and prevalent vertebral fractures were evaluated using plain lateral X-ray images. Thoraco-lumbar scoliosis was evaluated using dual-energy X-ray absorptiometric images. LBP was assessed using the visual analogue scale (VAS) and Rolland-Morris disability questionnaire (RDQ). METHODSThe prevalence of radiological lumbar lesion and LBP was compared between the RA and control groups. In the RA group, factors associated with lumbar lesion and LBP were analyzed using a multiple logistic regression model. RESULTSThe prevalence rates of spondylolisthesis and prevalent vertebral fracture were significantly higher in the RA group than in the control group; the prevalence of thoraco-lumbar scoliosis tended to be higher in the RA group. There was no significant difference in the average LBP-VAS between the groups. However, the percentage of analgesic drug use was significantly higher, and RDQ scores tended to be worse in the RA group than the control group. Multivariate analysis revealed that age and disease activity score were both related to LBP in the RA group. CONCLUSIONSRA patients are more likely to have radiological lumbar lesions. LBP in RA patients is well controlled, similar to the level in the healthy population; however, disease activity was related to LBP in RA patients. These results suggest that disease control is important for lumbar care in RA patients.