Before You Call It Severe

A clinical brief for referring providers — week 1 of a 4-part series on severe and difficult-to-control asthma.

Quick question before you read on: In what proportion of patients assumed to have severe asthma is asthma not actually the correct diagnosis?

a) 2–5% b) 12–50% c) Under 1%

The label "severe asthma" carries real consequences — biologics, specialist referral, and often years of oral steroids. It is worth being certain before applying it.

GINA 2026 draws a line that is easy to miss in a busy clinic. Difficult-to-treat asthma is persistent symptoms or exacerbations despite medium- or high-dose ICS with another controller. Severe asthma is the subset that stays uncontrolled after adherence, technique and comorbidities have been confirmed and addressed.

The distinction matters because most patients labeled severe are not.

The five-step check before the label sticks

Confirm the diagnosis. Spirometry with bronchodilator response; consider methacholine challenge. Evaluate for mimics — vocal cord dysfunction, COPD, cardiac disease, bronchiectasis.

Assess adherence. Refill records and FeNO trends, asked non-judgmentally. Up to 50% of "uncontrolled" asthma is non-adherence.

Verify inhaler technique. 70–80% of patients demonstrate errors. Reassess at every visit, not just the first.

Identify and treat comorbidities. Allergic rhinitis and sinusitis, GERD, obesity, OSA, vocal cord dysfunction, anxiety and depression, ABPA.

Address modifiable risk factors. Allergen exposure where sensitized, smoking, occupational exposure, and medications — beta-blockers, NSAIDs, ACE inhibitors.

70–80% of patients demonstrate an inhaler technique error. The medication never reaches the lung, and the chart reads as treatment failure.

Only when all five are optimized and the asthma remains uncontrolled is the patient genuinely severe, and a candidate for biologic therapy.

Want the five-step check walked through with your team?

Dr. Joel Mensing of the Chest & Sleep Team runs a 20-minute clinical briefing covering the GINA 2026 difficult-to-treat versus severe distinction, the adherence and technique audit your MAs can run before the patient leaves the room, and when a referral is worth making. Lunch provided. No pitch — just the clinical walkthrough.

Call (847) 860-7250.

The answer

12–50%. In up to half of patients assumed to have severe asthma, asthma is not the correct diagnosis (GINA 2026). The rest of this update is what to check first.