Allopurinol Medication Adherence as a Mediator of Optimal Outcomes in Gout Management

Optimizing adherence to allopurinol for gout: patients' perspectives

AIMS

Poor adherence to allopurinol among people with gout contributes to suboptimal gout management. This study sought to understand the facilitators and barriers to allopurinol adherence across the three stages of medication adherence, and patient perspectives on strategies to improve adherence, including self-monitoring urate concentration.

METHODS

Semi-structured interviews were conducted with 26 people with gout, previously or currently taking allopurinol. De-identified verbatim transcripts were thematically analysed using an inductive and deductive approach.

RESULTS

Facilitators of adherence during allopurinol initiation were motivation to prevent gout flares and trust in the advice of their healthcare professionals (HCPs). Reluctance to commence long-term medication was a barrier to allopurinol initiation. Believing in the effectiveness and necessity of allopurinol and reminder systems were facilitators of implementation. Barriers to implementation included forgetfulness, gout flares and limited feedback on allopurinol's effectiveness. Patients discontinued therapy when allopurinol was perceived as ineffective or unnecessary. Discontinuation coincided with patients experiencing gout flares while adhering to allopurinol and receiving suboptimal advice about gout management. Patients identified receiving accurate advice from HCPs and regular urate monitoring for feedback on allopurinol's effectiveness as potential strategies to improve adherence. Perceived benefits of self-monitoring urate as a strategy to promote adherence included the ability to self-manage gout and make informed decisions about allopurinol therapy with their HCP.

CONCLUSION

Patient perceptions of the effectiveness and necessity of allopurinol influenced intentional adherence during medication initiation, implementation and discontinuation. Strategies that inform patients of their urate control and provide accurate medical advice have the potential to improve adherence to allopurinol.

Cause-Specific Mortality in Patients With Gout in the US Veterans Health Administration: A Matched Cohort Study

OBJECTIVE

To compare all-cause and cause-specific mortality risk between patients with gout and patients without gout in the Veteran's Health Administration (VHA).

METHODS

We performed a matched cohort study, identifying patients with gout in the VHA from January 1999 to September 2015 based on the presence of ≥2 International Classification of Diseases, Ninth Revision codes for gout (274.X). Gout patients were matched up to 1:10 on birth year, sex, and year of VHA enrollment with patients without gout and followed until death or end of study (December 2017). Cause of death was obtained from the National Death Index. Associations of gout with all-cause and cause-specific mortality were examined using multivariable Cox regression.

RESULTS

Gout (n = 559,243) and matched non-gout controls (n = 5,428,760) had a mean age of 67 years and were 99% male. There were 246,291 deaths over 4,250,371 patient-years in gout patients and 2,000,000 deaths over 40,441,353 patient-years of follow-up in controls. After matching, gout patients had an increased risk of death (hazard ratio [HR] 1.09 [95% confidence interval (95% CI) 1.08-1.09]), which was no longer present after adjusting for comorbidities (HR 0.98 [95% CI 0.97-0.98]). The strongest association of gout with cause-specific mortality was observed with genitourinary conditions (HR 1.50 [95% CI 1.47-1.54]). Gout patients were at lower risk of death related to neurologic (e.g., Alzheimer's disease and Parkinson's disease) (HR 0.63 [95% CI 0.62-0.65]) and mental health (HR 0.66 [95% CI 0.65-0.68]) conditions.

CONCLUSION

A higher risk of death among gout patients in the VHA was related to comorbidity burden. While deaths attributable to neurologic and mental health conditions were less frequent among gout patients, genitourinary conditions were the most overrepresented causes of death.

Incidence, Prevalence, and Burden of Gout in the Veterans Health Administration

OBJECTIVE

To determine the prevalence, incidence, and burden of gout in the Veterans Health Administration (VHA) from 2005 to 2014.

METHODS

We used national VHA data from January 1999 to December 2014 to determine the annual incidence and prevalence of gout in the VHA. Gout burden to the VHA was determined by the proportion of patients with an encounter related to gout. Rates of urate-lowering therapy (ULT) and opiate use were determined annually. Characteristics of those with and without gout were compared using 2014 data.

RESULTS

From 2005 to 2014, gout prevalence in the VHA increased from 4.2% to 5.8%, while disease incidence ranged from 5.8 to 7.4 cases per 1,000 patient-years. Gout prevalence was highest among men, older patients, and non-Hispanic black patients. During 2014, 4.0% of all inpatient or outpatient encounters and 1.3% of hospitalizations were gout related. Administration of ULT remained stable over the 10-year period, with 46% of gout patients receiving ULT in 2014. In contrast, 16.4% of prevalent gout patients were receiving a weak opioid in 2014, nearly doubling the prescription rate of weak opioids in 2005, while the use of stronger opioids did not change significantly over this period. Patients with gout had greater comorbidity and health care utilization than patients without gout.

CONCLUSION

The burden posed by gout in the VHA is considerable and increased between 2005 and 2014. While the use of ULT has remained stable, the use of opioid therapy has increased among patients with gout.

Compliance of Primary Care Providers With Gout Treatment Recommendations—Lessons to Learn: Results of a Nationwide Survey

Objectives: Gout is generally managed in the primary health care sector. Compliance of primary care physicians with gout management recommendations has been shown to be insufficient in the past. The primary aims of this study were to assess primary care providers' knowledge regarding gout and to determine if their treatment decisions are influenced by recommendations. Facing considerable variations in postgraduate training options in Austria, we secondly looked for possible knowledge differences between urban and rural areas and eastern and western parts of Austria.

Methods: We conducted a survey among 343 primary care physicians in Austria, using a questionnaire consisting of 10 questions on acute, intercritical and general gout management. Gout treatment recommendations served as the therapeutic gold standard.

Results: Of the 343 physicians surveyed, 336 completed the questionnaire, leading to a very high return rate of 98%. 289 (86%) physicians were aware of the agreed-upon SUA target (<6 mg/dl). 323 (96.1%) reported change of therapy in case of missing this target. 112 (33.3%) physicians voted for long term ULT. No geographical differences in knowledge regarding gout or its management were revealed, except that colchicine was rated as being a safe medication significantly more often in rural areas (p = 0.035) and in western Austria (p = 0.014).

Conclusion: As opposed to former studies, gout knowledge among primary care physicians has improved - however, treatment patterns are still not fully concordant with gout recommendations. Our findings may help to better tailor future postgraduate training to improve primary care physicians' education in gout.

Variation in methods, results and reporting in electronic health record-based studies evaluating routine care in gout: A systematic review

OBJECTIVE

To perform a systematic review examining the variation in methods, results, reporting and risk of bias in electronic health record (EHR)-based studies evaluating management of a common musculoskeletal disease, gout.

METHODS

Two reviewers systematically searched MEDLINE, Scopus, Web of Science, CINAHL, PubMed, EMBASE and Google Scholar for all EHR-based studies published by February 2019 investigating gout pharmacological treatment. Information was extracted on study design, eligibility criteria, definitions, medication usage, effectiveness and safety data, comprehensiveness of reporting (RECORD), and Cochrane risk of bias (registered PROSPERO CRD42017065195).

RESULTS

We screened 5,603 titles/abstracts, 613 full-texts and selected 75 studies including 1.9M gout patients. Gout diagnosis was defined in 26 ways across the studies, most commonly using a single diagnostic code (n = 31, 41.3%). 48.4% did not specify a disease-free period before 'incident' diagnosis. Medication use was suboptimal and varied with disease definition while results regarding effectiveness and safety were broadly similar across studies despite variability in inclusion criteria. Comprehensiveness of reporting was variable, ranging from 73% (55/75) appropriately discussing the limitations of EHR data use, to 5% (4/75) reporting on key data cleaning steps. Risk of bias was generally low.

CONCLUSION

The wide variation in case definitions and medication-related analysis among EHR-based studies has implications for reported medication use. This is amplified by variable reporting comprehensiveness and the limited consideration of EHR-relevant biases (e.g. data adequacy) in study assessment tools. We recommend accounting for these biases and performing a sensitivity analysis on case definitions, and suggest changes to assessment tools to foster this.

The Role of a “Treat-to-Target” Approach in the Long-Term Renal Outcomes of Patients with Gout

Background: Although gout is accompanied by the substantial burden of kidney disease, there are limited data to assess renal function as a therapeutic target. This study evaluated the importance of implementing a “treat-to-target” approach in relation to renal outcomes. Methods: Patients with gout who underwent continuous urate-lowering therapy (ULT) for at least 12 months were included. The effect of ULT on renal function was investigated by means of a sequential comparison of the estimated glomerular filtration rate (eGFR). Results: Improvement in renal function was only demonstrated in subjects in whom the serum urate target of <6 mg/dL was achieved (76.40 ± 18.81 mL/min/1.73 m2 vs. 80.30 ± 20.41 mL/min/1.73 m2, p < 0.001). A significant difference in the mean change in eGFR with respect to serum urate target achievement was shown in individuals with chronic kidney disease stage 3 (−0.35 ± 3.87 mL/min/1.73 m2 vs. 5.33 ± 11.64 mL/min/1.73 m2, p = 0.019). Multivariable analysis predicted that patients ≥65 years old had a decreased likelihood of improvement (OR 0.31, 95% CI 0.13–0.75, p = 0.009). Conclusions: The “treat-to-target” approach in the long-term management of gout is associated with better renal outcomes, with a greater impact on those with impaired renal function.

Adherence and Outcomes with Urate-Lowering Therapy: A Site-Randomized Trial

PURPOSE

The purpose of this study was to test a pharmacist-led intervention to improve gout treatment adherence and outcomes.

METHODS

We conducted a site-randomized trial (n=1463 patients) comparing a 1-year, pharmacist-led intervention to usual care in patients with gout initiating allopurinol. The intervention was delivered primarily through automated telephone technology. Co-primary outcomes were the proportion of patients adherent (proportion of days covered ≥0.8) and achieving a serum urate <6.0 mg/dl at 1 year. Outcomes were reassessed at year 2.

RESULTS

Patients who underwent intervention were more likely than patients of usual care to be adherent (50% vs 37%; odds ratio [OR] 1.68; 95% confidence interval [CI] 1.30, 2.17) and reach serum urate goal (30% vs 15%; OR 2.37; 95% CI 1.83, 3.05). In the second year (1 year after the intervention ended), differences were attenuated, remaining significant for urate goal but not for adherence. The intervention was associated with a 6%-16% lower gout flare rate during year 2, but the differences did not reach statistical significance.

CONCLUSIONS

A pharmacist-led intervention incorporating automated telephone technology improved adherence and serum urate goal in patients with gout initiating allopurinol. Although this light-touch, low-tech intervention was efficacious, additional efforts are needed to enhance patient engagement in gout management and ultimately to improve outcomes.

Retreatment with Pegloticase after a Gap in Therapy in Patients with Gout: A Report of Four Cases

INTRODUCTION

Pegloticase, a potent uricolytic biologic enzyme, has been shown to be an effective therapeutic option in patients with uncontrolled gout. However, there are limited data on clinical response after a gap in therapy and retreatment with pegloticase.

CASE SERIES

This report describes four patients with chronic gout who were successfully managed with pegloticase and were retreated following a gap in therapy. Patient charts from a practice-based rheumatology clinic were retrospectively analyzed; four male patients, aged 70-75 years, with chronic gout and a more than 4-week gap in pegloticase therapy were reviewed. Before pegloticase treatment, patients had received allopurinol or febuxostat, but they continued exhibiting symptoms, including visible tophi and serum uric acid (SUA) levels of 5.2-10.2 mg/dL (309-607 μmol/L), despite oral urate-lowering therapy. The first pegloticase treatment (8-mg infusion every 2 weeks) lasted 22-124 weeks. Pegloticase resolved tophi and improved SUA to below 1.5 mg/dL (less than 89 μmol/L); however, patients discontinued pegloticase because of symptom resolution, poor adherence, or personal reasons. Following treatment gaps (12-156 weeks), symptoms and SUA levels increased and patients were retreated with pegloticase (4-147 weeks). In three of four patients, reinitiating pegloticase lowered SUA levels to below 1.0 mg/dL (less than 59 μmol/L) and resolved symptoms. One patient experienced an infusion reaction and discontinued; no infusion reactions, gout flares, or adverse events occurred among the other three patients.

CONCLUSION

Retreatment with pegloticase after a gap in therapy appears to be an effective and tolerated option in prior responders.

FUNDING

Horizon Pharma.