The Burden of Severe Asthma in France: A Case-Control Study Using a Medical Claims Database

Abstract

Severe asthma (SA) is defined by treatment intensity. The availability of national databases allows accurate estimation of the prevalence, long-term outcomes, and costs of SA. To provide accurate information on SA, focusing on comorbidities, mortality, health care resource consumption, and associated costs. A cohort of patients with SA identified in 2012 was extracted from a French representative claims database and followed for 3 years. Their characteristics, comorbidities, mortality, and direct costs were compared with a matched control group without asthma. A total of 690 patients with SA were matched to 2070 patients without asthma (mean age, 61 years; 65.7% women). The prevalence of SA was estimated to be 0.18% to 0.51% of the French adult population. Comorbidities were more frequent in patients with SA (73.9% suffered from cardiovascular disease vs 54.3% in controls; P < .001). A total of 58.7% of patients with SA used oral corticosteroids (OCS) in 2012 with a mean intake of 3.3 boxes/year/patient and 9% received ≥6 dispensings of OCS. A total of 6.7% were treated by omalizumab. Patients with SA were more frequently hospitalized (33.2% vs 19.7%; P < .001), more frequently consulted a general practitioner (97.8% vs 83.9%; P < .001) (9.8 ± 6.8 vs 6.2 ± 5.3 consultations/year; P < .001), and 31% have consulted a private respiratory physician. Compared with controls, 3-year cumulative mortality was higher in SA (7.1% vs 4.5%; P= .007). Direct medical cost was $9227 versus $3950 (P < .001) mostly driven by medication costs. The prevalence of SA in the French adult population is at least 18 of 10,000. Burden of disease is high with respect to comorbidities, mortality, and asthma-related health care resource use.