Background Risk of cardiovascular mortality is increased in patients with ankylosing spondylitis (AS). Chronic inflammation plays a crucial role in the development of accelerated atherosclerosis. TNFa is a pro-inflammatory cytokine which may be a key mediator in the pathophysiology of atherogenesis. This cytokine reduces the activity of insulin and causes insulin resistance (IR).
Objectives We assessed the effect of infliximab treatment on insulin sensitivity and metabolic parameters in patients with AS.
Methods In this prospective study, 20 consecutive AS patients (11 men and 9 women, mean age 39±10 and mean disease duration 12±7 years) fulfilling the modified 1984 New York criteria for AS were investigated. All patients were treated with iv infliximab (5 mg/kg, 0, 2, 6. week and ewery 8 weeks). A complete biochemical profile was obtained before and after 24 weeks of infliximab therapy (BASDAI, BASFI, ESR, CRP, hsCRP, lipid parameters, fasting glucose, insulin, HbA1C, waist circumference, weight, BMI, blood pressure). No patients were taking medications known to affect glucose, lipid metabolism and blood pressure. The Homoeostasis Model Assessment of Insulin Resistance Index (HOMA-IR) and Quantitative Insulin Sensitivity Check Index (QUICKI) were used to measure IR.
Results After 24 weeks of infliximab treatment there was no statistically significant difference in fasting glucose levels, fasting insulin, HOMA-IR, QUICKI, HbA1C and blood pressure. Weight (84±18 vs. 87±16, p=0.002), body-mass index (29±6 vs. 30±5, p=0.001), waist circumference (101±12 vs. 104±11, p=0.014) and LDL level (112±42 vs. 127±36, p=0.014) increased significantly from baseline.
Conclusions Infliximab treatment caused an increase in weight, BMI, waist circumference and LDL level but no change in IR. Cytokines associated with inflammation reduce appetite. Amelioration of anorexia with anti-TNF therapy may explain these results. Further studies are needed to clarify the role of factors that contribute to accelerated atherosclerosis in AS.
Disclosure of Interest None declared