Association Between Severity of Anaphylaxis and Co-occurrence of Respiratory Diseases: A Systematic Review and Meta-analysis of Observational Studies

Asthma is very prevalent in all grades of severity of anaphylaxis. Asthma and chronic obstructive pulmonary disease (COPD) have been associated with the severity of anaphylaxis. Objective: We carried out a systematic review and meta-analysis to assess the influence of respiratory diseases on the severity of anaphylaxis. We searched PubMed/MEDLINE, EMBASE, and the Web of Science for observational studies. The target studies were those that compared the severity of anaphylaxis between patients who had or did not have respiratory diseases. A total of 13 studies assessed the severity of anaphylaxis in respiratory disease. Respiratory disease increased the severity of anaphylaxis (OR, 1.87; 95%CI, 1.30-2.70), as did asthma (OR, 1.89; 95%CI, 1.26-2.83). For the meta-analysis of all studies (adjusted and nonadjusted), COPD increased the severity of anaphylaxis (OR, 2.47; 95%CI, 1.46-4.18). In the case of asthma studies, only 1 study assessed the influence of severity of asthma on severity of anaphylaxis. Evidence showing that respiratory disease increases the severity of anaphylaxis is low to moderate, although studies do not usually assess the importance of severity of asthma.