Ognjenovic M1, Raymond W1, Inderjeeth C1, Keen H1, Preen D1, Nossent J1.
J Rheumatol. 2020 Feb 15. pii: jrheum.190675. doi: 10.3899/jrheum.190675. [Epub ahead of print]
To compare the long-term prevalence, incidence and outcomes of vertebral fracture (VF) between ankylosing spondylitis (AS) patients and matched controls, including the role of extra-articular manifestations (EAM) and osteoporosis.
State-wide observational study using linked health data for 2,321 AS patients and 22,976 controls presenting to hospital from 1980-2015. Data were analysed using incidence rates (per 1000 person-years) and ratios (IRR), multivariable Cox-proportional hazard regression and Kaplan-Meier survival curves.
Over a median 13.92 (IQR 7.58, 21.67) years of follow-up, AS patients had a greater VF prevalence and incidence of developing a new VF compared to controls (9.3% vs 2.5%, 6.8% vs 1.9%, respectively, all p<0.001). AS patients had an increased risk of developing a VF after adjustment for age, sex and osteoporosis (HR=2.55; 95%CI: 2.11, 3.09) compared to controls, and remained throughout the study period. AS patients were 5-years younger at time of first VF (p=0.008) and had a greater likelihood of a re-current VF (IRR=4.64; 95%CI: 4.54, 4.75) compared to respective controls. Mortality overall was comparable between AS patients and controls after adjustment for age, sex, osteoporosis and VF status (HR=0.90; 95%CI: 0.80, 1.01). CONCLUSION: The significantly increased risk for VF in AS patients has not altered following the introduction of TNFi treatment. While AS patients experience a first VF at a younger age than controls, this does not lead to an increased risk of death.