A Bayesian Framework to Assess the Usability of Dry Powder Inhalers in a Cohort of Asthma Adolescents in Italy

The useability of DPIs (dry powder inhalers) depends on several factors that are influenced by the patients’ subjectivity and objectivity. The short-form global usability score (S-GUS), a specific tool for the quick ranking and comparison in real life of an inhaler’s usability, was used to investigate six of the most prescribed DPIs (Breezhaler, Diskus, Ellipta, Nexthaler, Spiromax, and Turbohaler) in consecutive asthma patients aged <18 years. A Bayesian indirect comparison (IC) was carried out to merge all pairwise comparisons between the six DPIs. Thirty-three subjects participated: eighteen tested Breezhaler, Spiromax, Nexthaler, and Ellipta simultaneously, while fifteen tested Breezhaler, Spiromax, Diskus, and Turbohaler. The estimates of the S-GUS, by the IC model, allowed us to rank the DPIs by their degree of usability: Ellipta, Diskus, and Spiromax were classified as “good to pretty good” (S-GUS > 15), while Spiromax, Turbohaler, and Breezhaler were classified as “insufficient” (S-GUS < 15). The multidomain assessment is recommended in asthma adolescents in order to approximate the effective usability of different DPIs as best as possible. The S-GUS proves particularly suitable in current clinical practice because of the short time required for its use in adolescents.

Experimental Evaluation of Dry Powder Inhalers During In- and Exhalation Using a Model of the Human Respiratory System (xPULM™)

Dry powder inhalers are used by a large number of patients worldwide to treat respiratory diseases. The objective of this work is to experimentally investigate changes in aerosol particle diameter and particle number concentration of pharmaceutical aerosols generated by five dry powder inhalers under realistic inhalation and exhalation conditions. The active respiratory system model (xPULM&trade;) was used as a model of the human respiratory system and to simulate a patient undergoing inhalation therapy. A mechanical upper airway model was developed, manufactured and introduced as a part of the xPULM&trade; to represent the human upper respiratory tract with high fidelity. Integration of optical aerosol spectrometry technique into the setup allowed for evaluation of pharmaceutical aerosols. The results show that the upper airway model increases the resistance of the overall system and act as a filter for bigger particles (&gt;3 &micro;m). Furthermore, there is a significant difference (p &lt; 0.05) in mean particle diameter between inhaled and exhaled particles with the majority of the particles depositing in the lung. The minimum deposition is reached for particle size of 0.5 &micro;m. The mean particle number concentrations exhaled are 2.94% (BreezHaler&reg;), 2.66% (Diskus&reg;), 10.24% (Ellipta&reg;) 2.13% (HandiHaler&reg;) and 6.22% (Turbohaler&reg;). In conclusion, the xPULM&trade; active respiratory system model is a viable option for studying interactions of pharmaceutical aerosols and the respiratory tract in terms of applicable deposition mechanisms. The model can support the reduction of animal experimentation in aerosol research and provide an alternative to experiments with human subjects.

Experimental Evaluation of Dry Powder Inhalers During In- and Exhalation Using a Model of the Human Respiratory System (xPULM™)

Dry powder inhalers are used by a large number of patients worldwide to treat respiratory diseases. The objective of this work is to experimentally investigate changes in aerosol particle diameter and particle number concentration of pharmaceutical aerosols generated by five dry powder inhalers under realistic inhalation and exhalation conditions. The active respiratory system model (xPULM&trade;) was used as a model of the human respiratory system and to simulate a patient undergoing inhalation therapy. A mechanical upper airway model was developed, manufactured and introduced as a part of the xPULM&trade; to represent the human upper respiratory tract with high fidelity. Integration of optical aerosol spectrometry technique into the setup allowed for evaluation of pharmaceutical aerosols. The results show that the upper airway model increases the resistance of the overall system and act as a filter for bigger particles (&gt;3 &micro;m). Furthermore, there is a significant difference (p &lt; 0.05) in mean particle diameter between inhaled and exhaled particles with the majority of the particles depositing in the lung. The minimum deposition is reached for particle size of 0.5 &micro;m. The mean particle number concentrations exhaled are 2.94% (BreezHaler&reg;), 2.66% (Diskus&reg;), 10.24% (Ellipta&reg;) 2.13% (HandiHaler&reg;) and 6.22% (Turbohaler&reg;). In conclusion, the xPULM&trade; active respiratory system model is a viable option for studying interactions of pharmaceutical aerosols and the respiratory tract in terms of applicable deposition mechanisms. The model can support the reduction of animal experimentation in aerosol research and provide an alternative to experiments with human subjects.

Medication Administration With Inhalers or Nebulizers

Delivery of medication via metered-dose inhalers to children or adults with asthma, or adults with chronic obstructive pulmonary disease at emergency departments or intensive care units, may be as effective as nebulizers in terms of clinical parameters and health care resource use. Limited data on adverse events showed no significant differences between metered-dose inhalers and nebulizers. No evidence was found on the clinical effectiveness of dry powder inhalers in comparison with nebulizers or metered-dose inhalers. No evidence was found on the cost-effectiveness of medication administration via metered-dose inhalers, nebulizers, or dry powder inhalers in comparison with each other. No evidence-based guidelines with recommendations regarding the comparative use of metered-dose inhalers, dry powder inhalers, or nebulizers for administration of medication were identified.

The environmental impact of inhalers for asthma; a green challenge and a golden opportunity

The propellants used in metered-dose inhalers (MDIs) are powerful greenhouse gases, which account for approximately 13% of the NHS’s carbon footprint related to the delivery of care. Most MDI use is in salbutamol relievers in patients with poorly controlled disease. The UK lags behind in this regard with greater reliance on salbutamol MDI and correspondingly greater greenhouse gas emissions; roughly treble our European neighbours’. There has been a broad switch towards MDIs in the UK over the last 20 years to reduce financial costs such that two-thirds of asthma patients in the UK are on treatment dominated by salbutamol MDI. Strategies that replace overuse of reliever MDIs with regimes emphasising inhaled corticosteroids have the potential to improve asthma control alongside significant reductions in greenhouse gas emissions. Real-world evidence shows that once-daily long-acting combination dry-powder inhalers can improve compliance, asthma control and reduce the carbon footprint of care. Similarly, maintenance and reliever therapy (MART) which uses combination reliever and inhaled steroids in one device (usually a dry-powder inhaler) can simplify therapy, improve asthma control and reduce greenhouse gas emissions. Both treatment strategies are popular with patients, most of whom are willing to change treatment to reduce their carbon footprint. By focussing on patients who are currently using high amounts of salbutamol MDI, and prioritising inhaled steroids via dry-powder inhalers, there are golden opportunities to make asthma care more effective, safer and greener.