Pediatric Asthma: 2020 Global Initiative for Asthma (Prystowsky, 10/2020)

Many thanks to Sutter Medical Group of the Redwoods Pediatrician, Dr. Brian Prystowsky, for an amazing (and quite unique) Grand Rounds presentation this week on the "New" Global Initiative for Asthma (GINA) 2020 guidelines. 

Dr. Prystowsky took us to The Land of Make Believe and introduced us to:

• The 2020 Global Initiative for Asthma (aka GINA, the elephant in the room)
• Simba (Symbicort=formoterol/budesonide)
• Bert and Ernie (SABA=Albuterol)
• Jose Canseco (inhaled corticosteroids), and
• "The Purple One" (Advair) 

Stick with me here, and the teaching will stick with you. The 46-page GINA Pocket Guide is available for your here for your bedtime reading enjoyment. 

Asthma management has been upended this year by the 2020 GINA Guidelines.  Here's why.

Traditional management of mild asthma, mild/moderate intermittent asthma, persistent asthma, and exercise-induced asthma has been based on a few standard assumptions that may need some re-evaluation

•  First, that bronchoconstriction is the fundamental pathophysiological problem in asthma
• Second, that intermittent symptoms only need intermittent treatment, a short-acting beta agonist (SABA, e.g. albuterol). 
• Third, that inhaled corticosteroids (ICS) work for patients with persistent symptoms if prescribed chronically but are not indicated for intermittent symptoms. 
• Standard management of asthma involved prn SABA for patients with intermittent/exercise-induced asthma and addition of daily maintenance ICS with SABA as rescue for those with persistent symptoms.

ALL this is changing! A batch of studies suggest that asthma is likely more of an inflammatory condition that we might've previously thought-- or at least that inhaled corticosteroids (ICS) used in combination with a Rescue beta agonist is associated with better outcomes. 

The big practice change from GINA is moving away from use of SABA (albuterol) PRN to use of Symbicort PRN for asthmatics over 12. Symbicort, by the way, is a combination inhaler, which includes Budesonide (ICS) and Formoterol (LABA).

Studies in favor of  SYMBICORT PRN for the treatment of asthma: 

NEJM 2018 study (patients >12 with mild asthma x 52 weeks) found that patients treated with Symbicort PRN (compared with SABA prn in one arm and ICS maintenance with SABA prn) had higher percentage of weeks well controlled, LOWEST rate of severe exacerbation and lower median daily steroid dose (57mcg vs. 340mcg in ICS maintenance).

A NEJM 5/2019 study (patients >18 with mild asthma x 52 weeks) had similar findings: lower exacerbation rate, lowest number of severe exacerbations, and lower mean steroid dose.

A study from Thorax 2/2014 study (of patients >12 with exercise induced asthma, x6 weeks) found use of Symbicort PRN had best symptomatic control (compared to SABA prn and ICS maintenance/SABA prn) with much less steroid exposure.

Btw, Steroid exposure in an older study from Lancet 2011 (children 5-18 years old with mild persistent asthma) was associated with 1.1 cm growth restriction. Unclear how clinically significant this is, but as Dr. Brian said, parents don't want their children to be growth restricted..

What about "The Purple One"?

It seems that "the purple one" (aka ADVAIR; fluticasone/salmeterol) is not as effective as Symbicort in the care of asthma. 

Lancet 2011 study (5-18 years, 44 weeks) found that compared to PRN SABA, a QVAR+SABA prn vs. QVAR maintenance + SABA prn did not improve outcomes.

A 1/2020 study from Journal of Allergy and Clinical Immunology (mild asthma, ages 6-17 years) found that the use of QVAR+ SABA prn vs. QVAR maintenance + SABA prn had basically equal outcomes, except children had higher rates of steroid exposure in the maintenance group

And a study from Journal of Allergy and Clinical Immunology 12/2014 (ages 12-64) found Symbicort (vs. ADVAIR) had less exacerbations, lower oral steroid rates,  and less ER visits (though same hospitalization rates).

Can formoterol be an effective rescue?  Yes And is it safe in young children? Yes.

Compared to salmeterol, formoterol has a more rapid onset of action (at 3 minutes) at all doses

A study of 300 children in Pediatric Allergy and Immunology (3/2019) ages 8 months to 4 years found no safety concerns with the use of formoterol in children.

What are Dr. Brian's take home points for GINA?

• For children over age 12, Symbicort should be used both as rescue and maintenance as a PRN. Children will get at least as good control (maybe better) and will get less steroid.
• For children under age 12, the evidence is still not clear enough to change the historical practice. Continue to use albuterol PRN with ICS prn vs. ICS daily.

Thanks neighbors! And thanks Dr. Brian!