Self-Monitoring of Urate Concentration Could Benefit Gout Management

Sophie L. Stocker, PhD

Credit: LinkedIn

Self-monitoring of urate concentration using a point-of-care (POC) device for blood glucose may improve adherence to urate-lowering therapy (ULT) among individuals with gout.¹

The proof-of-concept feasibility study showed that patient-led monitoring supported the maintenance of allopurinol adherence and helped patients attain and maintain target urate concentrations, potentially reducing the incidences of gout flares.

“This approach to gout management has the potential to shift clinical practice toward empowering people to be invested in their gout management,” wrote the investigative team, led by Sophie L. Stocker, PhD, school of pharmacy, faculty of medicine and health, University of Sydney.

Despite the effectiveness of ULT, such as allopurinol, for long-term management of gout, up to half of patients discontinue therapy within the first six months in Australia. Factors impacting adherence to ULT include education for its role in preventing gout flares and the experiences of healthcare providers in providing gout management advice.³ Self-monitoring, using a biomarker, is recognized by global health organizations, including the World Health Organization (WHO), for allowing active patient participation in their health care.⁴

Thus, self-monitored point-of-care urate level testing may improve adherence to ULT by supporting patients in understanding how the therapy impacts gout.¹ Despite the availability of effective medicine, a measurable biomarker, and POC devices, Stocker and colleagues noted that self-monitoring remains underexplored in gout. In this study, the team examined the impact of urate self-monitoring on adherence to allopurinol, urate concentration control, and the incidence of gout flares.

The study was conducted from June 2021 to April 2023 and recruited patients across Australia from a database of people with gout or by advertisements on social media. Participants were trained on a POC device to self-monitor urate concentration and received allopurinol every 3 months. Each participant manually recorded urate concentrations using the POC device at least once a month for 12 months and these data were collected during monthly telehealth visits with a study investigator.

Adherence to the medication was measured using medication event monitoring technology on the bottle of allopurinol. Participants were monitored for time spent below the target urate concentration (<0.36 mmol/L) and were informed staying below would reduce their risk of gout flares.

Overall, 32 patients with gout were enrolled in the analysis—most were male (94%) and more than 50 years old (74%). The most common dosing regimen of allopurinol was 300 mg one-daily and the average urate concentration at baseline was 0.33 mmol/L. Each participant recorded their urate concentration an average of 18 times and measured consistently throughout the 12 months.

A total of 9 participants remained within the target urate concentration range, while a single participant was above the urate concentration range, for the study period. The time spent within the target urate concentration range was increased 1.3-fold (79% to 100%; P = .346) from quarter 1 to quarter 4 of the 12 months.

Meanwhile, approximately half of patients (48%) reported gout flares. Among these participants, the incidence of gout flares decreased by 1.6-fold (8 to 5; P = .25) during the study period. Regarding adherence, there were 1315 missed doses of ULT during the study, but 91.2% of doses were taken as prescribed.

Moreover, 773 events of suboptimal implementation were identified, including 58 occasional missed doses, 619 repeated missed doses, 92 repeated drug holidays, and 4 occasional drug holidays. Most (94%) of the study population persisted with allopurinol, with only two discontinuations over 12 months.

Stocker and colleagues noted the persistence in allopurinol may reflect the real-time feedback on urate control provided by self-monitoring, as patients can contextualize behavior and inform their understanding of the inflammatory condition.

“Given that most people with gout discontinue ULT within six months of their first prescription, the evaluation of urate self-monitoring in people with gout who are initiating or reinitiating ULT would be of interest because real-time feedback on urate control may assist in encouraging people with gout to persist with ULT, particularly when the risk of gout flares is high,” they wrote.

References

1. _{Michael TJF, Wright DFB, Chan JS, et al. Patient-Led Urate Self-Monitoring to Improve Clinical Outcomes in People With Gout: A Feasibility Study. ACR Open Rheumatol. Published online April 9, 2024. doi:10.1002/acr2.11666}
2. _{Coleshill MJ, Day RO, Tam K, et al. Persistence with urate-lowering therapy in Australia: A longitudinal analysis of allopurinol prescriptions. Br J Clin Pharmacol. 2022;88(11):4894-4901. doi:10.1111/bcp.15435}
3. _{Spragg JCJ, Michael TJF, Aslani P, et al. Optimizing adherence to allopurinol for gout: patients' perspectives. Br J Clin Pharmacol. 2023;89(7):1978-1991. doi:10.1111/bcp.15657}
4. _{World Health Organization. WHO Guideline on Self-Care Interventions for Health and Well-Being, 2022 Revision. Geneva: World Health Organization; 2022. https://www.who.int/publications/i/item/9789240052192}