There is currently a limited amount of information available on the incidence and prevalence of<unk> , and the various rates reported in the literature are most likely an underestimate. Although<unk>  is thought to be rare overall, its prevalence among the population at large is not known. However, numerous studies have been conducted on its incidence and prevalence among patients presenting with asthma and exertional dyspnea. A<unk>  incidence rate of 2% has been reported among patients whose primary complaint was either asthma or dyspnea; the same incidence rate has also been reported among patients with acute asthma exacerbation. Meanwhile, much higher<unk>  incidence rates have also been reported in asthmatic populations, ranging from 14% in children with refractory asthma to 40% in adults with the same complaint. It has also been reported that the<unk>  incidence rate is as high as 27% in non-asthmatic teenagers and young adults. Data on the prevalence of<unk>  is also limited. An overall prevalence of 2.5% has been reported in patients presenting with asthma. Among adults with asthma considered "difficult to control", 10% were found to have<unk>  while 30% were found to have both<unk>  and asthma. Among children with severe asthma, a<unk>  prevalence rate of 14% has been reported. However, higher rates have also been reported; among one group of schoolchildren thought to suffer from exercise-induced asthma, it was found that 26.9% actually had<unk>  and not asthma. Among intercollegiate athletes with exercise-induced asthma, the<unk>  rate has been estimated at 3%. In patients presenting with symptoms of dyspnea, prevalence rates ranging from 2.8% to 22% have been reported in various studies. It has been reported that two to three times more females than males suffer from<unk> .<unk>  is especially common in females who suffer from psychological problems. There is an increased risk associated with being young and female. Among patients suffering from<unk> , 71% are over the age of 18. In addition, 73% of those with<unk>  have a previous psychiatric diagnosis.<unk>  has also been reported in newborns with gastroesophageal reflux disorder (GERD).
Vocal cord dysfunction
Vocal cord paresis
Velopharyngeal insufficiency
Laryngotracheal stenosis
Pulmonary hypoplasia
Tracheomalacia
Congenital limb deformities
Tracheal agenesis