9 September 2019

Concerns grow over misuse of SABAs

Research Respiratory

More than two thirds of people who buy over-the-counter relievers are overusing the medication, a study of NSW pharmacies has revealed.

A team at the Woolcock Institute of Medical Research surveyed around 400 people who purchased short-acting beta agonists (SABAs) across 18 pharmacies in the state.

Around 70% of people surveyed used their relievers more than twice per week, which is more frequent than is recommended. As expected, the people who were heavily dependent on SABAs had worse asthma symptoms.

Around 6% of people who overused reliever medication self-reported that they had well-controlled asthma, compared with around half of the people who didn’t rely on SABAs.

Even more worrying, 60% of SABA overusers reported that they had uncontrolled asthma, compared with just 16% of non-overusers.

“Asthma control was assessed using GINA-defined control,” the researchers wrote in the paper. “Asthma status was labelled as controlled, partially controlled or uncontrolled depending on selected responses.”

Around 80% of people surveyed self-reported that they had been diagnosed with asthma by a doctor.

The results were “cause for serious concern”, said Dr Greg Katsoulotos, a respiratory physician affiliated with The Woolcock Institute of Medical Research who was not involved in the study.

SABA overusers were at higher risk of potentially fatal asthma attacks, he said.

SABAs do not significantly reverse the inflammation and mucosal swelling associated with severe asthma.

Some people with asthma preferred salbutamol (ventolin) to preventers because it was cheap and provided “instant gratification” through immediate symptom relief, he said.

But people were “doing themselves an injustice” by making this their treatment of choice, he said.

“SABAs are only a short-term fix for a few hours,” he said. “They are just relaxing the tight muscle in the airway. So, they are not treating the underlying main pathology in the asthma.”

Around half of people in the survey said they had been instructed by their doctor to use preventer medication every day, but only around 27% did so.

“People seem to be managing their symptoms when they happen, but we really need to be encouraging them to take a more preventative approach,” Professor Sinthia Bosnic-Anticevich, a respiratory pharmacist at the Woolcock Institute of Medical Research and senior author of the study, said.

“There’s a huge opportunity in pharmacy because people come to the pharmacy pretty regularly and so we need to be targeting them at that point.”

In the survey, people said they didn’t take their preventer medication because they didn’t need it, forgot to take it, because of side effects, or because it didn’t work.

Combined therapies, which provide immediate relief as well as long-term inflammation control, could be a good option for some patients, Professor Bosnic-Anticevich said.

New evidence has demonstrated that even people with mild asthma could benefit from combined therapy, she said.

The Global Initiative for Asthma (GINA) recently recommended against SABA alone for mild asthma.

In what was described as the “most fundamental change in asthma management in 30 years”, GINA recommended that people with mild asthma be prescribed inhaled corticosteroid-containing treatment.

However, some people in the survey might have genuinely not benefited from taking preventer medication, particularly if they had been diagnosed as having asthma incorrectly, Dr Katsoloutos said.

“When you diagnose asthma based on symptoms there are quite a few people who are given the label but don’t actually have it and they are inappropriately given inhalers. So those people are not going to get any benefit from using an inhaler. I’m not sure they can benefit from the salbutamol either.

“There are lots of things that could mimic asthma. It could be post-nasal drip, reflux problems, they may have a cough from a medication that they are on, they may have a different lung disease altogether, like bronchiectasis or scarring of the lungs – fibrosis,” Dr Katsoloutos said.

BMJ Open 2019, 14 August