Background/Purpose: Psoriatic Arthritis (PsA) is an inflammatory arthritis affecting peripheral and axial joints in patients with psoriasis. The disease process in PsA comprises of complex bone involvement. A preliminary review of studies evaluating Osteoporosis in PsA provides inconsistent and conflicting results. The aim of this this study was to analyze Bone Mineral Density (BMD) in patients with (PsA), as well as to investigate its possible associations with measures of disease activity and functional capacity.

Methods: Consecutive Patients from PsA Clinic underwent BMD scan of spine L1-L4 and left Femoral Neck using Hologic Discovery A – 84248 model between March and May of 2015. BMD was expressed as g/cm2, Z-score and T-score. The percentage of patients with T-score ≤ -2.5 SD (WHO osteoporosis definition) and with Z-score ≤ -1.0 SD was calculated. Disease activity measures included: tender, swollen and damaged joint counts, patient and physician global assessment, presence of enthesitis, nail involvement and Psoriasis Area Severity Index (PASI) score. Laboratory tests included inflammatory markers ESR and CRP. Health Assessment Questionnaire (HAQ) and Short Form 36 Health Survey were used to assess functional status. Patients’ clinical, laboratory and radiological data were extracted from PsA program computer database. Statistical analysis included descriptive statistics, linear regression models and logistic regression models controlling for age.

Results: Total of 61 patients [38 males (mean age 56.57 ± 10.19 years) and 23 females (mean age 53.95 ± 10.76)] years were studied. According to WHO definition, spinal osteoporosis was found in 3% of patients and femoral neck osteoporosis in 5% of patients. Spinal osteopenia was found in 28% of patients and femoral neck osteopenia in 39%.

Disease activity measures of the recruited patients [mean (SD) or proportion] at the time of BMD assessment included: tender joint count 3.8 (7.7), swollen joint count 0.7 (1.7), clinically damaged joint count 9.1 (12.3), patient global 2.6 (0.9), physician global 1.8 (0.7), presence of enthesitis 7 (12%), nail involvement 10 (16%), ESR 14.8 (10.8), CRP 5.2 (3.3), HAQ 0.5 (0.4), Short Form -36 PCS 39.5 (10.4) and Short Form-36 MCS 50.1(12.5).

None of the clinical or laboratory features were associated with bone density either using linear regression with bone density in g/cm²measured by the BMD as outcome, or with logistic regression using low versus normal bone density as outcome.

Conclusion: In our cohort of PsA patients, prevalence of osteoporosis was not increased. BMD was not associated with disease activity or functional status.

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/osteoporosis-in-psoriatic-arthritis/