A 24-Year-Old Woman with a History of Anxiety and Asthma

A 24-year-old woman with a history of anxiety and asthma comes to the office due to wheezing.  She was diagnosed with asthma 3 years ago and has been intubated twice during that period, both for <24 hours.  She has been taking high-dose fluticasone/salmeterol and montelukast but has required frequent oral corticosteroids because "the attacks keep on happening."
In the past 6 months, the patient has been to the emergency department twice but was not admitted.  She says that the attacks come on suddenly, often due to stress, but occasionally also due to dust, cigarette smoke, and exercise.  The symptoms manifest as throat and chest tightness and cough.  There is no seasonal variation.
The patient has no nighttime awakenings due to shortness of breath or cough and nasal congestion.  She reports occasional symptoms of reflux, primarily when she eats in the late evening.  The patient demonstrates excellent inhaler technique.  She does not use tobacco, alcohol, or illicit drugs.  She works as a waitress, lives alone, and has no pets.
Blood pressure is 110/80 mm Hg, pulse is 74/min, and respirations are 14/min.  Pulse oximetry is 98% on room air.  She appears comfortable, and there is no accessory respiratory muscle usage.  Lung examination shows diffuse wheezes.
Spirometry shows forced expiratory volume (FEV₁) of 97% predicted, forced vital capacity (FVC) of 101% predicted, and FEV₁/FVC ratio of 0.94.  Lung volumes and diffusion capacity are normal.  Chest x-ray reveals no acute disease.
Which of the following is the best next step in management of this patient?

A) Add nasal fluticasone
B) Order a CT scan of the chest
C) Repeat spirometry with a flow-volume loop
D) Start fluoxetine
E) Start omeprazole