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A method to assess adherence in inhaler use through analysis of acoustic recordings of inhaler events.

D'Arcy S, MacHale E, Seheult J, Holmes MS, Hughes C, Sulaiman I, Hyland D, O'Reilly C, Glynn S, Al-Zaabi T, McCourt J, Taylor T, Keane F, Killane I, Reilly RB, Costello RW - PLoS ONE (2014)

Bottom Line: The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence.Repeated training reduced this to 7% of participants (p = 0.03).EudraCT 2011-004149-42.

View Article: PubMed Central - PubMed

Affiliation: Trinity Centre for Bioengineering, Trinity College Dublin, Dublin, Ireland.

ABSTRACT

Rationale: Poor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use.

Objectives: This paper introduces a device developed to create time stamped acoustic recordings of an individual's inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence.

Findings: The technology was validated by showing that the doses taken matched the number of audio recordings (r2 = 0.94, p<0.01). To demonstrate that audio analysis of inhaler use gives objective information, in vitro studies were performed. These showed that acoustic profiles of inhalations correlated with the peak inspiratory flow rate (r2 = 0.97, p<0.01), and that the acoustic energy of exhalations into the inhaler was related to the amount of drug removed. Despite training, 16% of participants exhaled into the mouthpiece after priming, in >20% of their inhaler events. Repeated training reduced this to 7% of participants (p = 0.03). When time of use was considered, there was no evidence of a relationship between adherence and changes in AQLQ (r2 = 0.2) or PEFR (r2 = 0.2). Combining time and technique the rate of adherence was related to changes in AQLQ (r2 = 0.53, p = 0.01) and PEFR (r2 = 0.29, p = 0.01).

Conclusions: This study presents a novel method to objectively assess how errors in both time and technique of inhaler use impact on clinical outcomes.

Trial registration: EudraCT 2011-004149-42.

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In (A) the rate of adherence by time of use for patients who improved by the minimum clinically important difference in AQLQ are shown in red and those who did not is shown, in black.Time of inhaler use did not relate to changes in clinical status. In (B) the adherence rate including the time and technique of use is shown. Those who had at least a minimum important clinically difference in AQLQ over the observation period are shown in blue, while those who did not are shown in green. There was a significant relationship between the rate of adherence and the outcomes in AQLQ when both time and technique were assessed. In (C) the rate of adherence by time of use for patients who changes in PEFR is shown, the red line is those who had a trend of improved PEFR and those who did not is shown, in blue. In (D) the adherence rate including the time and technique of use is shown, there was an association of the improvement in PEFR with increased inhaler use, blue and those who did not, green.
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pone-0098701-g007: In (A) the rate of adherence by time of use for patients who improved by the minimum clinically important difference in AQLQ are shown in red and those who did not is shown, in black.Time of inhaler use did not relate to changes in clinical status. In (B) the adherence rate including the time and technique of use is shown. Those who had at least a minimum important clinically difference in AQLQ over the observation period are shown in blue, while those who did not are shown in green. There was a significant relationship between the rate of adherence and the outcomes in AQLQ when both time and technique were assessed. In (C) the rate of adherence by time of use for patients who changes in PEFR is shown, the red line is those who had a trend of improved PEFR and those who did not is shown, in blue. In (D) the adherence rate including the time and technique of use is shown, there was an association of the improvement in PEFR with increased inhaler use, blue and those who did not, green.

Mentions: Among the study participants there was an overall significant increase in AQLQ (p<0.001) over the 12 weeks of study, see Table 4. An exploratory analysis was performed to relate the rate of adherence in those who achieved at least a minimum clinically important improvement in AQLQ of 0.5 (n = 28) and those who did not (n = 18) [21]. No statistical difference was observed between the two groups for age or baseline PEFR, however there was a statistical difference in the BMI's and AQLQ scores for the two groups (p = 0.04 and 0.02 respectively). For this analysis temporal adherence only considers whether two doses were taken in a day. When plotting rate of inhaler use (Figure 7A) no relationship between the rate of adherence and clinical outcomes was observed. When data on time and technique was combined a correlation between the AQLQ-improvers group and this combined adherence rate was observed; with a downward trend in adherence for the non-improving group, (p = 0.017) and an upward trend from improvers (p = 0.02), Figure 7B. The same analysis was carried out comparing those with improvements and no improvements in PEFR, n = 20 and n = 28 respectively. There was no statistical difference in the age, BMI, initial PEFR or AQLQ scores between these two groups. No relationship between adherence, calculated simply by time of use between improvers and decliners, was observed however using a composite rate of adherence showed a distinction in the trend between improvers and non-improvers in terms of their PEFR rate, p = 0.016, (Figure 7 C & 7D).


A method to assess adherence in inhaler use through analysis of acoustic recordings of inhaler events.

D'Arcy S, MacHale E, Seheult J, Holmes MS, Hughes C, Sulaiman I, Hyland D, O'Reilly C, Glynn S, Al-Zaabi T, McCourt J, Taylor T, Keane F, Killane I, Reilly RB, Costello RW - PLoS ONE (2014)

In (A) the rate of adherence by time of use for patients who improved by the minimum clinically important difference in AQLQ are shown in red and those who did not is shown, in black.Time of inhaler use did not relate to changes in clinical status. In (B) the adherence rate including the time and technique of use is shown. Those who had at least a minimum important clinically difference in AQLQ over the observation period are shown in blue, while those who did not are shown in green. There was a significant relationship between the rate of adherence and the outcomes in AQLQ when both time and technique were assessed. In (C) the rate of adherence by time of use for patients who changes in PEFR is shown, the red line is those who had a trend of improved PEFR and those who did not is shown, in blue. In (D) the adherence rate including the time and technique of use is shown, there was an association of the improvement in PEFR with increased inhaler use, blue and those who did not, green.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048229&req=5

pone-0098701-g007: In (A) the rate of adherence by time of use for patients who improved by the minimum clinically important difference in AQLQ are shown in red and those who did not is shown, in black.Time of inhaler use did not relate to changes in clinical status. In (B) the adherence rate including the time and technique of use is shown. Those who had at least a minimum important clinically difference in AQLQ over the observation period are shown in blue, while those who did not are shown in green. There was a significant relationship between the rate of adherence and the outcomes in AQLQ when both time and technique were assessed. In (C) the rate of adherence by time of use for patients who changes in PEFR is shown, the red line is those who had a trend of improved PEFR and those who did not is shown, in blue. In (D) the adherence rate including the time and technique of use is shown, there was an association of the improvement in PEFR with increased inhaler use, blue and those who did not, green.
Mentions: Among the study participants there was an overall significant increase in AQLQ (p<0.001) over the 12 weeks of study, see Table 4. An exploratory analysis was performed to relate the rate of adherence in those who achieved at least a minimum clinically important improvement in AQLQ of 0.5 (n = 28) and those who did not (n = 18) [21]. No statistical difference was observed between the two groups for age or baseline PEFR, however there was a statistical difference in the BMI's and AQLQ scores for the two groups (p = 0.04 and 0.02 respectively). For this analysis temporal adherence only considers whether two doses were taken in a day. When plotting rate of inhaler use (Figure 7A) no relationship between the rate of adherence and clinical outcomes was observed. When data on time and technique was combined a correlation between the AQLQ-improvers group and this combined adherence rate was observed; with a downward trend in adherence for the non-improving group, (p = 0.017) and an upward trend from improvers (p = 0.02), Figure 7B. The same analysis was carried out comparing those with improvements and no improvements in PEFR, n = 20 and n = 28 respectively. There was no statistical difference in the age, BMI, initial PEFR or AQLQ scores between these two groups. No relationship between adherence, calculated simply by time of use between improvers and decliners, was observed however using a composite rate of adherence showed a distinction in the trend between improvers and non-improvers in terms of their PEFR rate, p = 0.016, (Figure 7 C & 7D).

Bottom Line: The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence.Repeated training reduced this to 7% of participants (p = 0.03).EudraCT 2011-004149-42.

View Article: PubMed Central - PubMed

Affiliation: Trinity Centre for Bioengineering, Trinity College Dublin, Dublin, Ireland.

ABSTRACT

Rationale: Poor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use.

Objectives: This paper introduces a device developed to create time stamped acoustic recordings of an individual's inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence.

Findings: The technology was validated by showing that the doses taken matched the number of audio recordings (r2 = 0.94, p<0.01). To demonstrate that audio analysis of inhaler use gives objective information, in vitro studies were performed. These showed that acoustic profiles of inhalations correlated with the peak inspiratory flow rate (r2 = 0.97, p<0.01), and that the acoustic energy of exhalations into the inhaler was related to the amount of drug removed. Despite training, 16% of participants exhaled into the mouthpiece after priming, in >20% of their inhaler events. Repeated training reduced this to 7% of participants (p = 0.03). When time of use was considered, there was no evidence of a relationship between adherence and changes in AQLQ (r2 = 0.2) or PEFR (r2 = 0.2). Combining time and technique the rate of adherence was related to changes in AQLQ (r2 = 0.53, p = 0.01) and PEFR (r2 = 0.29, p = 0.01).

Conclusions: This study presents a novel method to objectively assess how errors in both time and technique of inhaler use impact on clinical outcomes.

Trial registration: EudraCT 2011-004149-42.

Show MeSH