Impact of Health Literacy on Teaching Correct Inhaler Use in COPD, Asthma

A recent study found that teach-to-goal methods are more effective than brief interventions in metered-dose inhaler education for patients with chronic obstructive pulmonary disease (COPD) and asthma, but results may vary depending on levels of health literacy.

When educated on metered-dose inhaler (MDI) use with teach-to-goal methods, patients diagnosed with asthma and chronic obstructive pulmonary disease (COPD) experienced a lower rate of posteducation MDI misuse than those educated by brief interventions, according to a recent study published in Respiratory Medicine.

However, patients with low health literacy, an issue more common in older patients (aged 65 and above), experienced a higher rate of posteducation MDI misuse than patients with adequate health literacy.

Researchers aimed to investigate risk factors for MDI misuse among older inpatients with asthma and/or COPD and to compare how different educational interventions impact posteducation inhaler technique rates for older and younger patients.

Incorrect technique in using MDIs is a significant issue for older patients with asthma or COPD. Therefore, it is important to investigate possible risk factors that affect this group of patients, the authors wrote.

The present study is a secondary analysis of data pulled from 5 previous prospective interventional studies. These studies included 394 patients with a mean age of 51.9 years; 67% of patients were female, 90.6% were Black and 20% were aged 65 or older. Patients were diagnosed with either asthma or COPD and hospitalized at 2 urban academic hospitals. The timeframe for enrollment in these studies was 2007 to 2017.

Researchers assessed patients’ vision and health literacy. Patients were screened for health literacy using the Short Test of Functional Health Literacy in Adults (STOFHLA) if their vision was sufficient. The STOFHLA measured reading comprehension by requiring patients to correctly select missing words to finish given sentences. A score of 23/36 or higher on the STOFHLA denotes adequate health literacy and a score lower than 23/36 means low health literacy.

A 12-step checklist assessed patients’ MDI technique before and after receiving inhaler training. Less than or equal to 9 out of 12 steps correct on the checklist identified MDI misuse.

All 5 studies assigned patients to 1 of 3 MDI educational interventions:

  • Teach-to-Goal (TTG), which follows a teach-back method in which a demonstration is given followed by the patient teaching the information back in a 3-round cycle
  • Virtual Teach-to-Goal (V-TGG), which is the virtual version of TGG
  • Brief Intervention (BI), which consists of a 1-time, simple, verbal instructions

Most of the patients (189, or 47.9%) were assigned to TTG, followed by 142 (36.0%) to V-TTG, and 63 (15.9%) to BI.

At baseline, 88.8% of patients misused their MDIs as assessed by the 12-step checklist. Scores averaged 6.49 out of 12. There was no significant difference in baseline misuse between older and younger patients, patients with poor and sufficient vision, or patients with high and low literacy levels.

After receiving education about how to use these inhalers, MDI scores improved across all 3 educational interventions, with the average score increasing to 10.3 out of 12. Among patients assigned to the BI group, significantly more (74.6%) continued incorrect inhaler use in comparison with those assigned to TGG or V-TTG interventions. In the BI group, no patient older than 65 improved their MDI technique.

Almost one-fifth (19.3%) of patients had low health literacy. When compared with those patients aged over 65, a higher proportion of those aged under 65 had adequate health literacy.

More (46.7%) patients with low health literacy continued MDI misuse post education compared with less (23.9%) patients with adequate literacy. This pattern was also present in the TGG and V-TGG groups. In the BI group, no significant effect of health literacy on posteducation MDI misuse rate was found.

A binary logistic analysis showed that a higher baseline MDI technique score, high health literacy, and TTG and V-TTG were all factors that decreased patients’ chances of MDI misuse post education.

Factors that did not significantly impact posteducation MDI misuse were age and visual acuity. While age was not a significant factor impacting MDI misuse, age was correlated with low health literacy. As health literacy was a significant factor in increasing MDI misuse, older adults may be at a higher risk for having incorrect inhaler techniques.

Limitations of this study include a relatively small sample size in the BI group compared with the size of the TGG and V-TTG groups, the authors wrote. They also noted that most patients analyzed were urban, female, and Black and so results may not be applicable to other groups. Because this study was a secondary analysis of previous data, researchers had limited data on age-specific questions. Another limitation was the study’s use of the STOHFLA, which requires adequate vision and therefore prevents researchers from assessing the health literacy of patients with poor vision.

The effectiveness of teach-to-goal methods lies in the continually tested learned material, enhancing memory and allowing education to be individually tailored to the patient, the authors said. TTG and V-TTG were less effective for those with low health literacy, which disproportionally affects older patients. Therefore, it is important to develop to individually tailored, patient-centered MDI educational interventions for this population, the researchers concluded.


Trela KC, Zajac P, Zhu M, Press VG. Health literacy and type of education intervention predicting post-education metered dose inhaler misuse. Respir Med. Published online July 12, 2022. doi:10.1016/j.rmed.2022.106930