Asthma monitoring in primary care: time to gather more robust evidence

For people with asthma, the control of symptoms is now the accepted goal of clinical management.¹ In everyday practice, clinicians use a mixture of clinical measures and an assessment of “the future risk of exacerbations”¹ to determine how aggressive they will be with pharmacological therapy, usually inhaled corticosteroids (ICS). Since there is a lack of correlation between symptoms, resolution of airway inflammation and bronchial hyper-responsiveness, primary care practitioners will often continue therapy with ICS at higher doses than required: if patients are stable, overtreatment is likely to continue, and there is a general reluctance by busy practicing clinicians to decrease the ICS dose at regular intervals.

In this issue of the PCRJ, Turton et al.² have completed an important pilot study exploring the use of point-of-care indirect bronchial hyperresponsiveness (BHR) testing with mannitol in order to monitor and (importantly) adjust the ICS dose. Despite the small numbers, the authors found that there were improvements in Asthma Quality of Life Questionnaire (AQLQ) scores that correlated with improvements in BHR after increases in ICS dosage. Conversely, where the indirect BHR measure was seen to be normal, the general practitioners (GPs) were able to reduce the ICS dose. If indirect BHR testing could predict reliably and consistently the physiological improvements in asthma markers that correlate with improvements in quality of care, and if it could be implemented efficiently, then this measurement tool would be very welcome indeed.

Unfortunately, the evidence for widespread adoption of indirect BHR testing is not conclusive. There have been studies³ that have found improved asthma control with the regular use of indirect BHR monitoring, all with increased use of ICS. Conversely, further studies^4,5 have revealed no real improvements in control. It is currently inappropriate to recommend that there be widespread adoption of a measurement technique that may lead to an increased use of medications such as ICS (with known increased risk of side effects) without clear and consistent evidence of improved outcomes for patients. As Turton et al. comment,² it is time to develop and implement larger trials based in primary care that utilise regular BHR testing to examine the long term health benefits of this monitoring.

Efficient implementation is also required. It is unlikely that busy GPs will have the time to commit to using this tool on their patients. Implementation will require the training of nursing or allied health staff to interact with patients — as Turton et al. found.² Team-based primary care is the key to successful implementation of this type of ongoing asthma assessment.⁶ In health systems where private practice dominates, a financial incentive may be required. Australia has successfully introduced multidisciplinary care planning ‘item numbers’ that provide financial incentives for general practices to employ practice nurses and to engage with other allied health providers.⁷ As a consequence, there has now been an exciting expansion in the educational and chronic disease management roles for practice nurses in Australia. Anecdotally, this role expansion has not widely embraced an “integrated platform of asthma education”.² Unless these financial incentives are established more broadly across primary care to actively foster team-based primary care with training and interest in comprehensive respiratory education, indirect BHR testing is unlikely to be widely implemented.

The increasing reality of limited health resources is forcing policy makers to demand sound economic data before they agree to any new financial reimbursement models. While cost-effectiveness analyses in primary care are more acceptable to clinicians, it is likely that these will have to be combined with cost-utility studies.⁸ GPs and other primary care clinicians fully understand that one of the confounders in understanding the real value of any new primary care respiratory intervention is patients' attendance for regular follow-up and ongoing medication compliance. As such, factoring in comprehensive measurement of patient preference in any economic analyses — using such tools as Discrete Choice Analyses (DCEs) — and the effects on such secondary outcomes as patient and carer satisfaction, will be integral to a fuller understanding of the economic value of such an innovation in primary care.⁹

The other hidden benefit in Turton et al.'s paper² is their identification of the increasing value of point-of-care testing in fostering improved compliance and patient empowerment when it is integrated into daily clinical management in primary care. Their qualitative analyses revealed increased understanding of the chronic nature of asthma and improved involvement in goal-setting between patients and their primary care health professional. Interestingly, these qualitative data² were gathered from BHR-positive patients, which casts some doubt on the external validity of the findings. As with many studies on asthma management in primary care, patients recruited into studies are already highly motivated and compliant. However, the value of point-of-care testing in primary care for fostering improved compliance and patient engagement cannot be underestimated: a study of point-of-care pathology testing versus testing provided by a pathology laboratory among 4,300 patients in rural and urban general practices across Australia found that the patients in the point-of-care testing arm were found to have the same or better medication compliance.¹⁰ Point-of-care testing will only increase in importance in primary care as we build and develop new partnerships with patients within an evolving team-based primary care structure.