A retrospective analysis comparing subjects with isolated and coexistent vocal cord dysfunction and asthma.

Vocal cord dysfunction (VCD) is often misdiagnosed as asthma or complicates coexisting asthma. This study aimed to identify distinguishing clinical characteristics in patients with VCD, asthma, and coexisting VCD and asthma. We conducted a retrospective analysis of demographic and clinical data from 292 patients with VCD, asthma, coexisting VCD and asthma, and control subjects from an outpatient university asthma/allergy clinic. Concomitant asthma was present in 32.6% of VCD subjects. Overall, 42.4 % of all VCD subjects were previously misdiagnosed as having asthma for an average of 9.0 years. Upper airway symptoms were more prevalent in the VCD population and nocturnal apnea was more prevalent in comorbid VCD and asthma compared with either condition alone. Irritable bowel syndrome and chronic pain were identified as new comorbidities associated with VCD. VCD subjects who had been misdiagnosed with asthma had significantly more health care and asthma medication use compared to VCD subjects who had not mimicked asthma. There was no difference in asthma severity between those with and without VCD. Comorbid VCD and asthma led to an increase in long-acting β-agonist use only, but no difference in health care usage, compared with asthma alone. These findings suggest that the main morbidity associated with VCD may not lie in its inherent disease process, but instead in its ability to mimic asthma.