Cognitive Testing Flags COPD Patients Unable to Maintain Proper Inhaler Technique

Patients with chronic obstructive pulmonary disease (COPD) who had cognitive impairment were prone to stop following correct inhaler technique within a month of training, a prospective single-center study found.

A score of 16 or below on the Thai version of the Montreal Cognitive Assessment (MoCA), indicating the presence of dementia, was independently associated with critical errors in inhaler use 1 month after proper inhaler technique training from a pharmacist (adjusted OR 12.7, 95% CI 1.8-88.2), reported Benjamas Chuaychoo, MD, PhD, of Mahidol University in Bangkok, Thailand, and co-authors.

Meanwhile, peers still demonstrating proper inhaler technique had average patient COPD Assessment Test scores improve from 11.4 to 8.9 (P=0.018), and the 6-minute walk distance increase from 351 m to 372 m (P=0.009), according to the prospective study published in BMC Pulmonary Medicine.

Inhaler use generally improved immediately after training but worsened in the month following instruction, researchers noted.

A MoCA score of 16 and below was seen in 28.1% of patients at the 1-month follow-up, and MoCA scores were lower in patients experiencing incorrect inhaler usage compared to those who were using inhalers correctly. The results, according to researchers, point to continuous inhaler education and eventually, assistance.

"Assessment of cognitive function, device selection, re-assessment of the technique, and repeated training should improve COPD management," Chuaychoo and colleagues suggested.

"Taken together, these findings suggest that some patients with MCI can be trained to use an inhaler correctly. However, patients with MoCA scores ≤16 might not be able to use inhaler devices correctly by themselves," they said.

A MoCA score ≤24 -- indicating a wider population with mild cognitive impairment or the various stages of dementia -- was not significantly associated with an incorrect inhalation technique at 1 month after training, according the authors.

Handheld inhaled bronchodilators are a mainstay treatment for COPD. Nebulized therapies are an alternative for those with cognitive, neuromuscular, or ventilatory impairments not able to get the full benefit of handheld inhalers.

COPD has been linked to an increased risk of cognitive impairment, including dementia, with impairments seen in both intermediate visual memory and visuospatial memory.

To enter the present study, which was conducted at a outpatient COPD clinic at Siriraj Hospital in Bangkok, patients demonstrated their inhaler technique on dummy devices. Face-to-face training was provided for those who demonstrated incorrect inhaler use, which was then practiced until correct technique was used. Follow-up assessments occurred 1 month later.

Out of 254 COPD patients assessed, 66 incorrectly performed a critical step of inhaler technique and agreed to participate in 1-month follow-up for the study.

On average, patients were 73 years old and 95.5% men. Three in four had moderate to severe COPD, and 93.3% had received some form of instruction regarding inhaler usage prior to the study.

Altogether, the 66 patients used 101 inhalers comprising 59 pressurized metered-dose inhalers (pMDIs) and a mix of dry powder inhalers (HandiHalers, Breezhalers, Turbuhalers, and Accuhalers) for the remainder.

Researchers note that the most common inhaler mistakes made by patients depended on the brand used, ranging from not keeping the inhaler in an upright position to not pressing the canister and inhaling at the same time. The most common error during the use of pMDIs, observed in 84.7% of individuals, was during the "inhale slowly and deeply" step, according to study authors.

Chuaychoo's group acknowledged that optimal inspiratory flow for each device was not directly measured and that the study's sample size was small.

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