Inhalation in Asthma and COPD With Spiromax and Turbuhaler
Inhalation in Asthma and COPD With Spiromax and Turbuhaler
This study shows that most patients, regardless of age or underlying disease severity, can achieve satisfactory inhalation manoeuvre parameters through empty versions of the Spiromax and Turbuhaler dry powder inhalers. Enhanced training was useful to improve the inhalation characteristics of those patients with peak inhalation flows <30 L/min, especially COPD patients using the Turbuhaler. The increases in response to enhanced training highlight that there is room for improvement and that training patients to use these devices can be valuable. Although better inhalation characteristics were achieved when inhaling through the empty Spiromax, it is doubtful that this would translate into clinical differences between the devices since equivalence between them has been shown among highly trained patients. PIF values were lower among the COPD patients and the young asthma patients than among the adults with asthma, and the healthy volunteers achieved the highest PIF; these results were as expected.
There were statistically significant differences in key parameters (PIF, maximum ΔP and ACC) between the Spiromax and Turbuhaler, with greater improvements overall typically seen in the Spiromax group. The exception was the higher maximum ΔP value achieved by the Turbuhaler group, limited to COPD patients after enhanced training. This result must be considered in the context that (1) after enhanced training, all COPD patients in both groups achieved the minimal flow (30 L/min) required for adequate drug delivery and (2) prior to enhanced training, one COPD patient using Spiromax, as opposed to five COPD patients using Turbuhaler, did not achieve the minimal required flow rate. It may be argued that these results are more reflective of clinical practice than the finding that no patients failed to reach the 30 L/min threshold after enhanced training. The reason for this is that few patients in clinical practice are likely to receive training that is comparative to the enhanced training of this study. Also, several studies have highlighted poor inhalation technique with DPIs in clinical practice. Usually, differences in flow characteristics between DPIs are related, at least in part, to different airflow resistance. However, the present results show the reverse. Since the patients likely used similar inspiratory effort with both devices, it would be expected that values for ΔP and PIF would be higher for Turbuhaler because of the higher resistance of this device. However these values were slightly higher for Spiromax and suggest that additional factors can influence the inhalation characteristics of an inhalation manoeuvre.
Consistent with previous studies enhanced training produced significant improvement in the inhalation parameters of individuals using both devices. Percentage increases in response to training were generally larger with Turbuhaler than Spiromax. Comparison between the two devices of the effects of enhanced training was consistent across the study groups: asthma patients of different ages, COPD patients and healthy adults. Smaller post enhanced training improvements with the Spiromax device may reflect increased ease of use or concordance during use and so the scope for improvement is reduced if patients have good technique from the outset. This notion is strengthened by the fact that a proportion of patients in the present study were already users of the Turbuhaler device, since pre-existing expertise in using the Turbuhaler should in theory reduce the scope for improvement with this device. The greatest improvements were in the acceleration rate (with a faster time to the PIF), highlighting the importance of training patients to inhale as fast as they can from the start to ensure better de-aggregation of the dose. An understanding of the time taken to device mastery (absence of critical errors) and maintenance of device mastery with Spiromax and Turbuhaler, and the identification of long-term real-life use of these two devices in a population of adults with asthma, await further study.
In addition to possible 'increased ease of use' or reduced need for training with Spiromax, patients may be more familiar with the 'look' of the Spiromax inhaler compared with the Turbuhaler because Spiromax has contours similar to those of an MDI (DuoResp® Spiromax PIL). The majority of patients with asthma (at least 80%) or COPD (approximately 60%) were using an MDI (for salbutamol) at the start of the study, compared with 30.4–51.9% who were using the Turbuhaler. However, whether this contributed to the significant differences seen between the devices (favouring Spiromax) is beyond the scope of the current study. Furthermore, this finding does not account for the significant differences between the devices seen in the healthy adult group. Neither patient preference nor opinion (such as familiarity) of the devices were assessed at any point during the study. The evaluation of patient device preference (Turbuhaler and Spiromax) awaits further study.
An important limitation of this study is the open-label design, with training provided by a highly trained researcher who also made the inhalation manoeuvre measurements. This may have introduced the potential for bias – there is a possibility that study participants would use a device they recognise slightly differently from a new device with which they are unfamiliar. Completion of the study at one clinic visit is another drawback in relation to applicability of the results because, in clinical practice, inhalers are used in a variety of different environments over long periods of time. It would be useful to investigate whether the improvements resulting from enhanced training would be maintained over time during routine use. It is also yet to be established how flow and pressure profiles might differ with empty devices (as used here) versus those administrating a drug dose. Study devices were otherwise unaltered, however, and resistance measurements were not affected by the absence of drug and powder vehicle. An additional limitation is the lack of information regarding drug delivery or clinical effect; given the current study design, a robust approach to clinical endpoints was not feasible, but the data suggest that comparisons involving clinical endpoints should be of interest.
Discussion
This study shows that most patients, regardless of age or underlying disease severity, can achieve satisfactory inhalation manoeuvre parameters through empty versions of the Spiromax and Turbuhaler dry powder inhalers. Enhanced training was useful to improve the inhalation characteristics of those patients with peak inhalation flows <30 L/min, especially COPD patients using the Turbuhaler. The increases in response to enhanced training highlight that there is room for improvement and that training patients to use these devices can be valuable. Although better inhalation characteristics were achieved when inhaling through the empty Spiromax, it is doubtful that this would translate into clinical differences between the devices since equivalence between them has been shown among highly trained patients. PIF values were lower among the COPD patients and the young asthma patients than among the adults with asthma, and the healthy volunteers achieved the highest PIF; these results were as expected.
There were statistically significant differences in key parameters (PIF, maximum ΔP and ACC) between the Spiromax and Turbuhaler, with greater improvements overall typically seen in the Spiromax group. The exception was the higher maximum ΔP value achieved by the Turbuhaler group, limited to COPD patients after enhanced training. This result must be considered in the context that (1) after enhanced training, all COPD patients in both groups achieved the minimal flow (30 L/min) required for adequate drug delivery and (2) prior to enhanced training, one COPD patient using Spiromax, as opposed to five COPD patients using Turbuhaler, did not achieve the minimal required flow rate. It may be argued that these results are more reflective of clinical practice than the finding that no patients failed to reach the 30 L/min threshold after enhanced training. The reason for this is that few patients in clinical practice are likely to receive training that is comparative to the enhanced training of this study. Also, several studies have highlighted poor inhalation technique with DPIs in clinical practice. Usually, differences in flow characteristics between DPIs are related, at least in part, to different airflow resistance. However, the present results show the reverse. Since the patients likely used similar inspiratory effort with both devices, it would be expected that values for ΔP and PIF would be higher for Turbuhaler because of the higher resistance of this device. However these values were slightly higher for Spiromax and suggest that additional factors can influence the inhalation characteristics of an inhalation manoeuvre.
Consistent with previous studies enhanced training produced significant improvement in the inhalation parameters of individuals using both devices. Percentage increases in response to training were generally larger with Turbuhaler than Spiromax. Comparison between the two devices of the effects of enhanced training was consistent across the study groups: asthma patients of different ages, COPD patients and healthy adults. Smaller post enhanced training improvements with the Spiromax device may reflect increased ease of use or concordance during use and so the scope for improvement is reduced if patients have good technique from the outset. This notion is strengthened by the fact that a proportion of patients in the present study were already users of the Turbuhaler device, since pre-existing expertise in using the Turbuhaler should in theory reduce the scope for improvement with this device. The greatest improvements were in the acceleration rate (with a faster time to the PIF), highlighting the importance of training patients to inhale as fast as they can from the start to ensure better de-aggregation of the dose. An understanding of the time taken to device mastery (absence of critical errors) and maintenance of device mastery with Spiromax and Turbuhaler, and the identification of long-term real-life use of these two devices in a population of adults with asthma, await further study.
In addition to possible 'increased ease of use' or reduced need for training with Spiromax, patients may be more familiar with the 'look' of the Spiromax inhaler compared with the Turbuhaler because Spiromax has contours similar to those of an MDI (DuoResp® Spiromax PIL). The majority of patients with asthma (at least 80%) or COPD (approximately 60%) were using an MDI (for salbutamol) at the start of the study, compared with 30.4–51.9% who were using the Turbuhaler. However, whether this contributed to the significant differences seen between the devices (favouring Spiromax) is beyond the scope of the current study. Furthermore, this finding does not account for the significant differences between the devices seen in the healthy adult group. Neither patient preference nor opinion (such as familiarity) of the devices were assessed at any point during the study. The evaluation of patient device preference (Turbuhaler and Spiromax) awaits further study.
An important limitation of this study is the open-label design, with training provided by a highly trained researcher who also made the inhalation manoeuvre measurements. This may have introduced the potential for bias – there is a possibility that study participants would use a device they recognise slightly differently from a new device with which they are unfamiliar. Completion of the study at one clinic visit is another drawback in relation to applicability of the results because, in clinical practice, inhalers are used in a variety of different environments over long periods of time. It would be useful to investigate whether the improvements resulting from enhanced training would be maintained over time during routine use. It is also yet to be established how flow and pressure profiles might differ with empty devices (as used here) versus those administrating a drug dose. Study devices were otherwise unaltered, however, and resistance measurements were not affected by the absence of drug and powder vehicle. An additional limitation is the lack of information regarding drug delivery or clinical effect; given the current study design, a robust approach to clinical endpoints was not feasible, but the data suggest that comparisons involving clinical endpoints should be of interest.
Source...