Key clinical point: Psoriatic arthritis (PsA) is associated with the risk for low bone mineral density (BMD), but this association is partially mediated by treatment with methotrexate or ciclosporin. Psoriasis excluding PsA in the absence of a secondary condition is not a risk factor for osteoporosis.
Major finding: PsA was associated with low BMD (β-coefficient = −0.014; P = .0006). However, the association became nonsignificant when patients were treated with methotrexate or ciclosporin (β-coefficient = −0.005; P = .28). Psoriasis without arthritis was not associated with low BMD or osteoporosis.
Study details: The data come from a cross-sectional study of 432,513 participants from the UK Biobank dataset.
Disclosures: The study was supported by the Zhejiang Provincial Natural Science Foundation for Distinguished Young Scholars of China and the National Natural Science Foundation of China. The authors declared no conflicts of interest.
“The associations between psoriasis and psoriatic arthritis (PsA) and osteoporosis/fracture are not fully understood. This study examined the relationship between psoriasis and PsA and bone mineral density (BMD) using a cross-sectional design that employed a Mendelian randomization approach to assess causality. A total of 4904 persons with psoriasis and 847 persons with PsA from the UK Biobank data set were included.
The investigators found that PsA was associated with low bone mineral density (β-coefficient = −0.014; P = .0006), but that psoriasis was not. The association between PsA and low BMD was not genetically determined. However, treatment with methotrexate or ciclosporin partially mediated the relationship between PsA and low BMD. This study underscores the importance of screening and preventing osteoporosis and osteopenia in people with PsA.”
Maria I. Danila, MD, MSc, MSPH
University of Alabama at Birmingham
Xia J et al. Ann Rheum Dis. 2020 Jul 31. doi: 10.1136/annrheumdis-2020-217892.