When do we consider deprescribing allopurinol (xanthine oxidase inhibitor) in an 85-year-old patient with hyperuricemia (urate level 0.4) and no recent gout flares, according to New Zealand (NZ) guidelines?

Deprescribing Allopurinol in an 85-Year-Old Patient with No Recent Gout Flares

Allopurinol should be continued lifelong in this 85-year-old patient with a serum urate level of 0.4 mmol/L and no recent gout flares, as discontinuation could lead to recurrence of gout attacks.

Rationale for Continuing Allopurinol

The 2016 EULAR guidelines clearly state that "SUA <6 mg/dL (360 mmol/L) should be maintained lifelong" 1. This recommendation is based on the understanding that:

1. Urate crystals can persist in joints even during asymptomatic periods
2. Discontinuation of urate-lowering therapy (ULT) often leads to recurrence of hyperuricemia and subsequent gout flares
3. The patient's current urate level of 0.4 mmol/L indicates good control on the current therapy

Effectiveness of Current Treatment

The patient's serum urate level of 0.4 mmol/L (approximately 6.7 mg/dL) is near but not below the recommended target of <0.36 mmol/L (<6 mg/dL) 1. This indicates that:

• The current allopurinol dose is effectively controlling urate levels
• The absence of recent flares suggests clinical stability on the current regimen

Special Considerations in Elderly Patients

For this 85-year-old patient, several factors should be considered:

• Renal function: Allopurinol dosing may need adjustment based on creatinine clearance 1
• Medication burden: While deprescribing unnecessary medications is important in elderly patients, allopurinol has demonstrated long-term benefits that outweigh risks when properly dosed
• Risk of recurrence: Discontinuation could lead to crystal reformation and recurrent gout attacks

Monitoring Recommendations

If continuing allopurinol, regular monitoring should include:

• Serum urate levels every 6-12 months
• Renal function tests
• Assessment for adverse effects
• Evaluation of gout symptoms

When to Consider Deprescribing

Despite the general recommendation for lifelong therapy, deprescribing might be considered in specific circumstances:

• Development of severe adverse reactions to allopurinol
• Terminal illness with limited life expectancy where medication burden reduction is prioritized
• Significant deterioration in renal function requiring reassessment of all medications

Important Caveats

• Allopurinol is not an innocuous drug: The FDA label states that "therapy in such patients should be carefully assessed initially and reassessed periodically to determine in each case that treatment is beneficial and that the benefits outweigh the risks" 2
• Gradual discontinuation: If deprescribing is deemed necessary, gradual dose reduction rather than abrupt discontinuation would be preferred to minimize risk of flare
• Prophylaxis consideration: If discontinuation is attempted, prophylactic anti-inflammatory therapy might be considered during the withdrawal period

Conclusion

Based on current guidelines, allopurinol should be continued in this patient despite advanced age and absence of recent flares. The medication is effectively controlling urate levels, and discontinuation poses a significant risk of gout recurrence which could negatively impact the patient's quality of life.