Bone mineral density, T- and Z-scores in young men with juvenile idiopathic arthritis

Background. Juvenile Idiopathic Arthritis (JIA) is a term used to classify a group of heterogeneous pediatric rheumatic diseases. Many of these conditions persist through adulthood. Presence of chronic inflammatory disease along with a glucocorticoid treatment is the risk factor of osteoporosis in young adult males. The purpose was to study the bone mineral density (BMD), T- and Z-scores in young adult males with JIA. Materials and methods. The study included 50 patients aged 19–25 years, divided into two groups: I — 25 apparently healthy young males; ІІ — 25 young men from different regions of Ukraine with a history of JIA in childhood, regardless of the presence or absence of active inflammation at the time of the observation. Two-energy X-ray densitometry (Prodigy, GE Lunar, Madison, USA) was performed at the D.F. Chebotarev Institute of Ge­rontology, Ukrainian Scientific-Medical Centre for the Problems of Osteoporosis, together with analysis of BMD, T- and Z-scores at different skeletal areas. Results. Young men with JIA and healthy individuals did not differ in age, height, weight and body mass index. Four patients with JIA (16 %) had fractures, while in the control group, there were no fractures. Negative impact of the JIA on the BMD was found in group II compared to group I. Lumbar spine BMD in group II was lower (p < 0.01) than in healthy subjects, as well as the Z-score (p < 0.001) in the L1-L4 lumbar spine region. BMD, T- and Z-scores in femoral neck region were lower in group II than in group I (p < 0.001; p < 0.001; p < 0.01, respectively). Significant differences between the two groups were found in total body BMD (p < 0.001), T-score (p < 0.01), Z-score (p < 0.05). Patients with JIA had lower BMD (p < 0.01) and T-score (p < 0.05) of the ultradistal radius. Decrease of BMD up to the level of osteopenia (Z-score < –2 SD) was found in 20 % patients at the level of L1-L4 lumbar spine, in 8 % — at femoral neck, in 12 % — at total body and in 8 % patients at the level of ultradistal radius. Conclusions. Young men with JIA aged 19–25 years had reduced total body BMD, T- and Z-scores, which indicate the negative impact of the disease on the bone tissue compared with healthy men of the corresponding age