Competence thresholds for the use of inhalers in people with dementia

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