Bronchial Thermoplasty for Severe Asthma
In the last ten years death from severe asthma in America has decreased. Unfortunately, over the same period of time, hospital admissions, missed school and work days, as well as health care expenditures for asthma have not correspondingly gone down. In other words, many people still suffer from asthma despite the incredible advances in asthma medications and published guidelines.
As an asthma specialist, I see several patients each week who fail to respond to low and medium dose inhaled steroids, in combination with other asthma medications and environmental controls. The good news is there are guidelines for treating patients that fail to respond to earlier steps in asthma treatment (combination inhalers and other anti-inflammatory agents and symptom relievers).
A major recommendation for treating moderate to severe asthma patients who have not adequately responded to inhalants, are allergic, and have required high doses of inhaled steroid and/or frequent oral or injectable steroids, is Xolair (omalizumab). Dr. Fred Little posted a nice review of this asthma drug eight years ago. It’s been available for more than a decade, but is only given by injection and extremely expensive. Despite the latter issue, most insurance plans will cover it after thorough review of the patient’s previous treatments and severity level. But what if you don’t respond to Xolair or perhaps don’t qualify for it (if you are not allergic you won’t qualify for it)?
A relatively new treatment for severe asthma has emerged over the last five years.
My other Health Pro colleague, John Bottrell, posted an informative review on Bronchial Thermoplasty (BT) two years ago. BT is a procedure performed by lung specialists who have undergone special training in this process. The procedure requires a patient, under sedation, to have a fiberoptic bronchoscope inserted through the mouth or nose, into the lungs in order to apply thermal energy (heat) to the walls of the small airways.
The heat is transmitted by radiofrequency ablation with strict temperature controls to prevent excessive damage and perforation. Radiofrequency ablation is not a new technology. Cardiologists have used it for years in order to treat certain types of cardiac arrhythmias (atrial fibrillation and certain disorders associated with rapid or irregular heart rates).
In the first few years, many asthma patients benefited from BT, experiencing fewer asthma attacks, ED visits, hospitalizations and need for oral steroid (as published in a two year follow-up). Quality of life parameters also improved significantly for these patients. But as in many circumstances involving a new procedure or treatment, long-term benefits and risks were a concern.
A recent article published in the Journal of Allergy and Clinical Immunology reported on long term safety and effectiveness of BT in patients followed for five years after the procedure. The study was called The Asthma Intervention Research 2 trial (AIR2).
In summary, the results showed that from the first year through five years after BT, patients:
-Had 48% fewer severe attacks
-Had 88% fewer emergency department visits
-Average inhaled steroid dose decreased by almost 20% (without a drop off in lung function)
-Respiratory adverse events and hospital admits did not change from the second through fifth year (the gains from BT were sustained)
-CAT scans of the lungs at five years showed no significant changes in airway structure as a result of BT.
One editorial pointed out that the control group (group of asthma patients followed over the same period of time who did not have BT) did not get CAT scans of the lung to compare to the study group who had BT.
People with very severe asthma are not considered good candidates for the procedure because of the risks of bronchoscopy. In addition, patients who have other underlying medical problems (severe heart disease or other respiratory conditions) may not be considered for BT.
Overall, BT appears to be another potentially helpful treatment for patients who fail to benefit from inhaled steroids, combination inhalers and other add-on asthma medications. Like Xolair, it is very expensive and has its own risks. Current national guidelines published in 2007 do not include BT. It will likely be in the next update. The good news is Bronchial Thermoplasty is FDA approved, insurances may cover it, and after five years of experience, it so far, appears to be safe and effective.