Monotherapy LAMA is Over-Used, Linked to Asthma Exacerbation Risk

Esme Baan, MD

Long-acting muscarinic antagonists (LAMA) are frequently prescribed out of step with guidance for treating patients with asthma, according to a new study.

In new data presented virtually during the European Respiratory Society (ERS) 2020 Congress this week, a team of investigators from the Netherlands and Belgium showed monotherapy LAMA is prevalent among nearly 40% of observed users with asthma—despite its indication being for add-on use.

Investigators, led by Esme Baan, MD, of the Department of Medical Informatics at the Erasmus University Medical Center in the Netherlands, sought to assess LAMA monotherapy prevalence and its association with severe asthma exacerbations among patients with the respiratory disease.

They conducted a cohort analysis in the Integrated Primary Care Information (IPCI) database using asthmatic patients aged 6-50 who were reportedly using LAMA therapy during follow-up. Their analysis included patient data from 2007-2017.

Asthma treatment periods were stratified by either monotherapy LAMA, double therapy (LAMA plus inhaled corticosteroid [ICS]), or triple therapy (LAMA + ICS + long-acting beta agonist [LABA]).

Baan and colleagues collected patient characteristics including age, sex, history of exacerbations, and comorbidities at the beginning of each treatment period. They conducted a Poisson regression analysis to calculate the relative rate (RR) of severe asthma exacerbations, with an adjustment for patient characteristics.

Median observed patient age was 41 years old with two-thirds (65.9%) being female.

Of all observed 3596 LAMA treatment periods, 1390 (38.7%) were considered LAMA monotherapy. Just 553 (15.4%) were double therapy, and 1653 (46.0%) were triple therapy.

Among all patients to use LAMA, investigators observed a relative severe asthma exacerbation risk of 1.58 (95% CI, 0.52 – 4.77; P = .42) among monotherapy patients versus double therapy patients. When excluding patients to have used triple therapy for asthma management, the relative risk of sever exacerbations increased to 5.72 (95% CI, 1.39 – 23.62; P = .02).

Other notable relative risks for severe exacerbation across all patients included being female (RR, 1.63; 95% CI, 1.10 – 2.42; P = .016) as well as a history of previous exacerbations (RR, 1.81; 95% CI, 1.63 – 2.00; P <.001).

Baan and colleagues concluded their findings allude to an over-reliance of LAMA—a designed add-on therapy—as a singular maintenance drug for asthma, for which it is clearly not benefitting. A missing piece of the asthma treatment regimen is all too apparent in these results.

“This observational study shows that LAMA is frequently prescribed as monotherapy (i.e. without concurrent ICS) which is associated with an increased risk of exacerbations,” they wrote. “This emphasizes the need to check for ICS use when prescribing LAMA to asthmatic patients.”

The study, “(in)Appropriate LAMA Prescribing in Asthma patients: a Cohort Analysis (the ALPACA study),” was presented at ERS 2020.