Clinical significance of Aspergillus sensitisation in bronchial asthma

Numerous studies have suggested a link between fungal sensitisation and severity of asthma. However, few studies have specifically evaluated the relationship between Aspergillus sensitisation and asthma severity. This study was aimed at investigating the clinical significance of Aspergillus sensitisation in asthma. In this prospective cross-sectional study, patients with asthma were subjected to pulmonary function test and an intradermal Aspergillus skin test (AST) apart from a detailed clinical history and physical examination. Assessment of asthma severity was carried according to the Global Initiative for Asthma (GINA) recommendations, Asthma Control Test (ACT) and the mini Asthma Quality of Life Questionnaire (mini AQLQ). Based on AST, the cases were dichotomised into Aspergillus-sensitive and AST-negative groups. There were 417 (193 males, 224 females; mean age, 34 years) asthmatic patients of whom 219 (52.5%) showed Aspergillus sensitisation. The severity of disease as per the GINA criteria and the dose of ICS required for asthma control were similar in the two groups. The Aspergillus-sensitive group had poorer pulmonary function than the AST-negative group [AST positive vs. negative: percentage predicted mean (SD) forced expiratory volume in the first second: 73.1(23.8) vs. 77.9(22.7), P = 0.04; mean (SD) FEV(1) /forced vital capacity (FVC) ratio: 68.2(13.3) vs. 74.3(15.7), P = 0.0001]. The mini AQLQ scores were similar in the two groups. In the ACT, the numbers of patients in the domain pertaining to nocturnal awakenings were significantly higher in the Aspergillus-sensitive group (P = 0.014). There was a weak association between Aspergillus sensitisation and severity of asthma. Whether Aspergillus sensitisation is causally linked to asthma severity remains to be seen.