Anti-IgE therapy for asthma: an audit at atertiary care centre in Saudi Arabia

Abstract

Background: Although anti-IgE therapy has been shown to offer numerous benefits, we suspect it is underutilized locally. To date, there are no studies on any aspect of its use in the Arab region. There is also no information on whether physicians follow current guidelines nor on patient response to this form of therapy.

Objective: Assess the use of omalizumab for patients with difficult asthma at a tertiary care center.

Design: Retrospective, descriptive.

Setting: Tertiary care hospital.

Patients and methods: Information was collected from medical records and interviews of all patients who received a minimum of 6 months of omalizumab, including data on practices of the prescribing physician (pulmonary versus allergy), indications, dose, subjective response, number of emergency room visits and hospitalizations, changes in asthma medications, adverse effects, and the setting for delivery of therapy.

Main outcome measures: Extent to which current guidelines for prescribing omalizumab were followed. Patient subjective and objective responses to treatment as reflected by changes in the use of medications and lung function before and after therapy.

Sample size: 50 patients.

Results: Of the 50 consecutive patients, 35 were female and the mean (SD) age was 46.3 (9.2) years. Only 28 patients (56 %) met all the criteria for the prescription of omalizumab as per current guidelines; 18 (64%) by pulmonary and 10 (36%) by allergy physicians (P less than .05). Pulmonary physicians performed more tests for conditions complicating or simulating asthma (P less than .05). The mean (SD) duration of treatment by omalizumab of 35 (22) months was longer in patients managed by allergists (42 [24] months) than pulmonary physicians (30 [21] months) (P greater than .05). Both physician groups prescribed a lower initial dose than recommended (P less than .05 recommended vs. prescribed). Patients reported a significant improvement in symptoms, reduction in the use of broncho-dilators and oral steroids and in the use of healthcare services (from 16.28 [7.9] to 2.08 [1.78], P less than .0001) mean values from sum of hospitalizations/year, ER visits/year, exacerbations/year, but not in other medications or pulmonary function tests (P greater than .05).

Conclusion: Despite several benefits, notably a reduction in utilization of health services and asthma medication, anti-IgE therapy is probably underutilized locally. Pulmonary physicians are more likely to follow the guidelines than allergy physicians. This study suggests that there is room for improvement in the prescription practices, particularly in dosing and the setting for delivery. Further multicenter prospective studies are required to identify gaps in the current practices and improve asthma management.

Limitations: Too few patients met inclusion criteria, lack of control group, and use of a subjective assessment for patient symptoms as opposed to validated questionnaires.

Conflict of interest: None.

Figure 1

Use of tests for conditions that can complicate or simulate asthma by pulmonary physicians and allergy physicians. ANCA: anti-neutrophil cytoplasmic antibody tests to rule out eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome), Eosinophilia: peripheral eosinophilia due to allergic bronchopulmonary aspergillosis (ABPA), PFT: pulmonary function tests for evidence of reversible obstruction and to rule out chronic obstructive lung disease, vocal cord dysfunction, Radiological: tests to rule out structural diseases of the lung (e.g. cystic fibrosis, bronchiectasis including ABPA, or endobronchial lesions, RAST: radioallergosorbent test for measuring human anti-Aspergillus fumigatus antibodies of the IgG class as part of ruling out ABPA.