Competence thresholds for the use of inhalers in people with dementia

the ability to learn three inhaler techniques of increasing levels of complexity was studied in 50 normal and demented inhaler-naive elderly people (mean age 81 years) with stable 10-point mini-mental test scores (MTS). There were 10 subjects in each of the following groups: MTS 8-10 (non-demented), MTS 7 (borderline), MTS 6 (mild dementia), MTS 5 and MTS 4 (2 moderate dementia groups). The techniques were taught on one day and reassessed on the following day on consecutive days in ascending order of complexity.

those with an MTS of 4 were unable to learn any of the techniques, while all the non-demented people could learn all three techniques. For the five-stage technique (standard metered dose inhaler) the 0% threshold (i.e. when none of the subjects was able to learn) was MTS 6, the 50% threshold (at least half but not all could learn) MTS 7 and the 100% threshold (all could learn) MTS 8. For the four-stage technique (inhaler with large spacer) the 0% threshold was MTS 5, the 50% threshold MTS 6 and the 100% threshold MTS 8. For the three-stage technique (inspiration-triggered inhaler) the 0% threshold was MTS 4, the 50% threshold MTS 5 and the 100% threshold MTS 7.

MTS can be used to determine the likelihood of a mild or moderately demented patient being able to learn a multiple-stage inhaler technique.