SAN FRANCISCO – Beware of vocal cord dysfunction mimicking asthma and other respiratory problems, especially in women, the overweight, and in patients with psychiatric diagnoses, according to a retrospective chart review of patients with the condition.
Of 100 patients diagnosed with vocal cord dysfunction at the University of Pittsburgh Medical Center’s outpatient adult allergy and immunology clinic, 86 were female, 68 were overweight, and 50 had psychiatric conditions.
For those patients especially, the possibility of vocal cord dysfunction (VCD) must be kept in mind when working up airway problems, said lead investigator Dr. Chitra Rao, an internal medicine resident at the medical center.
The reason is that VCD – in which the vocal cords spasm or even, to some extent, close on inspiration – is a notorious mimic of asthma, anaphylaxis, and other respiratory problems. Identifying it quickly not only speeds treatment but also prevents mistreatment for conditions patients do not have.
"I think it should definitely be on the differential, especially of severe or poorly controlled asthma. It can very much act like asthma," Dr. Rao said.
Dr. Rao and her colleagues reviewed the charts of 100 VCD patients and found that 26 had been misdiagnosed with asthma before presenting or being referred to the clinic; 9 were misdiagnosed with angioedema, 7 with anaphylaxis, and 3 with drug allergies.
In one, VCD had been mistaken for a reaction to omalizumab (Xolair). "While we were doing a desensitization challenge, [the patient] complained of the symptoms. We had a scope there and looked, and her vocal chords were spasming," Dr. Rao said.
The remaining 55 patients came to the clinic with undiagnosed respiratory complaints, including shortness of breath, wheezing, chest tightness, and throat tightness.
History and laryngoscopy ruled out asthma in half (13) of the patients mistakenly diagnosed with it; methacholine challenge testing excluded the other half.
Most patients were diagnosed with VCD by laryngoscopy, the remainder by history. Paradoxical vocal cord motion or other abnormalities were found by laryngoscope in 61 asymptomatic patients, without trigger maneuvers. A strong scent – Christian Dior’s "Poison" – was used to trigger an attack in some other patients to help seal the diagnosis.
"If you can actually illicit their attacks, it’s much easier for [patients] to buy into treatment," which includes breathing exercises, Dr. Rao said.
Vocal cord inflammation is the underlying problem in VCD, and the conditions that cause it, including gastroesophageal reflux (GERD), allergic rhinitis, and asthma – properly diagnosed – were common among patients. Treatment of those conditions can also help VCD.
GERD likely explains at least part of the link with obesity, but it remains unclear why women and people with anxiety and other psychiatric problems seem predisposed, Dr. Rao said.
Proper diagnosis is important. "If [attacks are] severe enough that [patients] go to the ER, they are going to get frequent steroids, which are not going to help them," Dr. Rao said.
"In severe cases, people who are not familiar with this disease may actually intubate [patients], and that’s actually counterproductive. It’s very difficult to extubate them because the whole underlying process is inflammation of the vocal chords. When you put in a breathing tube, it actually makes the symptoms worse," she said.
Dr. Rao said she has nothing to disclose.