Quantitative acoustic analysis of inhaler sounds for the objective assessment of inhaler adherence in patients with chronic respiratory diseases

Asthma and chronic obstructive pulmonary disease (COPD) are two of the most prevalent chronic respiratory disorders. Over 800 million people suffer from these diseases and over four million people die annually. Although both asthma and COPD are incurable, symptoms can be effectively controlled through the delivery of medication to the lungs. Inhaler devices are employed to deliver medication to the airways in the treatment of asthma and COPD. An inhalation step is required to extract the medication from the inhaler and deliver it to the airways. However, despite the proven clinical efficacy of inhaler devices, they can be difficult to operate and adherence levels for inhaler medications are subsequently poor (averaging around 50%). Poor inhaler adherence results in reduced clinical outcomes for patients and large financial costs for healthcare providers. Adherence is a critical aspect of inhaler use that should be continually monitored, however, there is currently a lack of objective methods available for this purpose.