Cognitive impairment linked to improper inhaler use 1 month after training

Key takeaways:

• A Montreal Cognitive Assessment score of 16 or less, which implies dementia, predicted errors in using inhalers.
• Use of proper inhaler technique declined 1 month vs. directly after training.

Patients with COPD and cognitive impairment had heightened odds for inaccurate use of their inhaler 1 month after receiving training, according to study results published in BMC Pulmonary Medicine.

“The Montreal Cognitive Assessment (MoCA) domains showing the highest impairment in our study were delayed recall, language and visuospatial/executive functions,” Chonnipha Iamthanaporn, BPharm, MBA, ambulatory care pharmacist at Siriraj Hospital in Bangkok, and colleagues wrote. “Patients with impairment in memory and executive functions might have difficulties in remembering how to use the inhaler and execute the correct technique.”

In a prospective observational study, Iamthanaporn and colleagues analyzed 66 patients (mean age, 73 years; 95.5% men) with COPD (75.8% moderate/severe) who incorrectly used an inhaler in one or more “critical steps” to see how face-to-face training with a pharmacist changes their technique.

Researchers evaluated patients’ technique directly after training and at 1 month, at which point they also sought to find what factors predict improper inhaler use by using scores from the MoCA, pulmonary function tests, 6-minute walk distance (6MWD), modified Medical Research Council (mMRC) scale, COPD Assessment Test (CAT), as well as other variables, including age, education, COPD duration, frequent exacerbations incidence, number of inhalers and prescribed inhaler usage duration.

This study assessed usage of pressurized metered-dose inhalers (59 devices) and dry powder inhalers (Turbuhaler [Symbicort, AstraZeneca], 11 devices; Accuhaler [Seretide, GlaxoSmithKline], 11 devices; Handihaler [Spiriva, Boehringer Ingelheim]/Breezhaler [Enerzair, Novartis], 20 devices). According to researchers, 71.2% of patients had a prescription for at least two inhalers, and 93.9% of the total cohort previously received instructions/training on how to use their inhaler.

Among those with a dry powder inhaler, every patient demonstrated proper use directly following training with a pharmacist, whereas 88.1% of patients with a pressurized metered-dose inhaler demonstrated proper use of the device.

The use of proper technique declined at 1 month, with correct usage found in only 16.9% of patients using pressurized metered-dose inhalers (P < .001), 55% of patients using Handihaler/Breezhaler (P = .04) and 72.7% of patients using Accuhaler.

When assessing possible predictors of improper inhaler usage at this timepoint, researchers found significant links with age older than 75 years (OR = 3.8; 95% CI, 1.3-10.9) and a MoCA score of 16 or less (OR = 10.9; 95% CI, 2.2-54.7) in univariable analysis.

The link between incorrect inhaler usage at 1 month and a MoCA score of 16 or less continued in multivariable analysis that accounted for age, education level, COPD duration, mMRC scale score and prescribed inhaler usage duration (adjusted OR = 12.7; 95% CI, 1.8-88.2), according to researchers.

“Simpler steps of inhaler use may improve the technique in patients with cognitive impairment,” Iamthanaporn and colleagues wrote.

Among patients who achieved proper technique for a minimum of one device containing a bronchodilator at 1 month (n = 31), researchers observed improvements at 1 month vs. baseline in CAT scores (11.4 ± 8.9 vs. 8.4 ± 5.5; P = .018) and 6MWD (351 m ± 9.5 m vs. 372 m ± 92 m; P = .009). Notably, no significant improvements in mMRC score or the five parameters measured in pulmonary function testing were found between baseline and 1 month in these patients.

Patients who failed to achieve proper technique for all their inhalation devices containing bronchodilators at 1 month (n = 35) only demonstrated significant improvement from baseline in inspiratory capacity (1.6 L ± 0.5 L vs. 1.7 L ± 0.5 L; P = .014), a measure in pulmonary function testing.

“Assessment of cognitive function, device selection, re-assessment of the technique, and repeated training should improve COPD management,” Iamthanaporn and colleagues wrote. “Further studies are needed to investigate the appropriate inhaler devices and techniques for COPD patients with cognitive impairment.”