To the Editor: The delivery of asthma drugs via inhalation offers the best balance between efficacy and safety. However, poor inhalation technique limits the efficacy of this approach. In recent years, there has been a progressive increase in the types of inhalation devices used in asthma management. We questioned whether this would lead to “inhaler-device polypharmacy”, a situation in which an individual used multiple types of inhalation device to deliver his or her asthma medications. We conducted a novel investigation of this issue in 2004.

We examined the computerised records of adults with asthma who had been enrolled in a standardised, evidence-based asthma management and education program1 between 2000 and 2004. We noted the number and type of inhaler devices used, as well as competence with each device (a trained asthma educator had observed and scored inhalation technique). We defined “inhaler-device polypharmacy” as the use of two or more different types of inhalation device. The devices assessed in the education program included a pressurised metered-dose inhaler (with and without a spacer), turbuhaler, accuhaler, aeroliser, autohaler, and handihaler. Nebuliser use was not included in the evaluation.

We assessed a total of 511 patients: 278 (107 male; mean age, 37 years) between 1 January 2000 and 1 January 2002 (Period 1), and 233 patients (55 male; mean age, 40 years) between 2 January 2002 and 1 January 2004 (Period 2).

Period 1 patients were distinct from Period 2 patients in that the latter began their treatment after the release of combination asthma therapy in a single inhaler, when polypharmacy may have been expected to diminish.

Inhaler-device polypharmacy was present in 203 (73%; 95% CI, 68%–78%) patients during Period 1 and 164 (70%; 64%–75%) in Period 2 (P = 0.3) (Box).

In Period 1, inhalation technique was inadequate with at least one device in 58 (29%) patients using inhaler polypharmacy and in 19 (25%) using only one device (Box). In Period 2, inhalation technique was inadequate with at least one device in 85 (52%) patients using inhaler polypharmacy and in 25 (36%) using only one device. In both Period 1 and Period 2 patients, inadequate inhaler technique with at least one device increased with the number of devices used (P values 0.02 and 0.05, respectively) (Box).

We conclude that inhaler-device polypharmacy is a common problem among adults with asthma. Inadequate inhalation-device technique is also common, especially among patients using three or more delivery devices. Inhaler-device polypharmacy could lead to poor asthma control through inadequate delivery of medication. Patients with poor asthma control should be evaluated for their asthma management skills, including competency in using inhaler devices. These skills should be optimised before a new drug and/or device is added to their treatment regimen. We see no justification for the use of more than two inhalation delivery devices in asthma management.