Early increase of abdominal adiposity in patients with spondyloarthritis receiving anti-tumor necrosis factor-α treatment.

OBJECTIVE

Patients with spondyloarthritis (SpA) receiving anti-TNF-α treatment have an increase in fat mass. This may be relevant to cardiovascular risk. The aim of this study was to estimate visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) changes by dual-energy x-ray absorptiometry (DEXA) in patients with SpA under anti-TNF-α therapy.

METHODS

We used an ancillary protocol to an open, prospective 2-year followup study of patients with SpA. Waist circumference (WC), body weight, body mass index, VAT, and SAT were measured at baseline, 6 months, and 1 and 2 years. Univariate and multivariate analyses were performed to assess variables associated with VAT and SAT changes.

RESULTS

A total of 85 patients were analyzed. Patients were 39.3 ± 11.4 years old and mean baseline Bath Ankylosing Spondylitis Disease Activity Index was 55.0 ± 20.2. Treatment was effective according to clinical and biological variables, and body weight increased by 0.9 ± 1.7 kg over 2 years. There was a significant gain in VAT after 6 months (13.7 ± 20.6 cm(2), p < 0.0001), 1 year (21.0 ± 26.6 cm(2), p < 0.0001), and after 2 years (29.1 ± 33.4 cm(2), p < 0.0001); and in SAT after 6 months (12.5 ± 27.4 cm(2), p < 0.0001), 1 year (27.1 ± 38.2 cm(2), p < 0.0001), and after 2 years (31.9 ± 53.2 cm(2), p < 0.0001). We could not find any determinant of these changes by multivariate analysis.

CONCLUSIONS

In patients with SpA receiving anti-TNF-α therapy, there is an early significant increase in abdominal obesity with significant increase in both VAT and SAT after 1 and 2 years of treatment. Prospective studies are required to investigate the relationship between these changes and cardiovascular risk.