Does Rheumatoid Cachexia Predispose Patients with Rheumatoid Arthritis to Osteoporosis and Vertebral Fractures?

To assess the prevalence and risk factors of rheumatoid cachexia (RC) and evaluate its relationship with osteoporosis and vertebral fractures (VF) in patients with rheumatoid arthritis (RA).

We enrolled into a cross-sectional study 178 consecutive patients with RA (82.6% women) with a mean age of 54.1 ± 11.5 years (25-82) and who fulfilled the American College of Rheumatology criteria for the classification of RA. Body composition, lateral VF assessment images, and scans of the lumbar spine and proximal femur were obtained using dual-energy x-ray absorptiometry. RC was defined by a fat-free mass index below the 10th percentile and a fat mass index above the 25th percentile compared with a reference population. VF were defined using Genant semiquantitative approach.

RC was observed in 96 patients (53.9%) and osteoporosis in 52 patients (29.2%). Comparison between women with and without RC showed that women with RC had a longer disease duration, higher disease activity variables, higher steroid cumulative dose, and higher proportion of patients with erosive arthritis. Women with RC had lower total hip bone mineral density (BMD) and T score than women without RC, while comparison in men found only body mass index to be significantly lower in men with RC. Regression logistic analysis showed an independent and significant association between RC and age and disease activity in women.

Our study showed that half of the patients with RA may have RC, a condition that was significantly associated with disease activity and low hip BMD, but not with VF.