Burden of severe spondyloarthritis in France: A nationwide assessment of prevalence, associated comorbidities and cost.

Objectives: To estimate the number of patients with severe spondyloarthritis (SpA) in France, describe their comorbidities and document and value their healthcare resource consumption.

Methods: Data were retrieved from an insurance claims database covering a 1/97 random sample of the French population. All patients benefiting from full insurance coverage ("ALD") for severe SpA in 2012 (including cases with structural damage and/or frequent flares) were identified, together with a control group frequency-matched by age and gender. Severe comorbidities were documented through ALD categories. Healthcare resource consumption was documented and valued from the payer's perspective. Rates of comorbidities and costs were compared in SpA patients versus controls using non-parametric testing.

Results: Overall, 827 patients with ALD status for severe SpA were identified (control group: n=2.481), corresponding to a prevalence rate of 0.18% [0.17-0.19] for SpA with ALD in the general population. Severe comorbidities more frequent in patients with SpA than in controls included inflammatory bowel disorders (odds ratio: 15.0 [6.2-36.2]), hypertension (2.5 [1.6-3.9]), atrial fibrillation (4.3 [1.9-9.6]) and major depressive disorder (2.1 [1.3-3.6]). Mean per capita annual direct healthcare expenditure was 3.6 [3.2-4.1]-fold higher in SpA patients (€6,122 [€5,838-€6,406]) than in controls (€1,682 [€1,566-€1,798]). Extrapolating to all patients in France, total healthcare cost attributable to severe SpA patients was €391 [€355-€426] million, with medication accounting for 53.8% of this cost.

Conclusions: The burden of severe SpA in France is substantial, due to the high prevalence, high direct costs and associated comorbidities.