Analysis of allopurinol prescription suggests clinical inertia to increase doses
Fernando Perez-Ruiz*, Nerea Perez-Herrero**, Leire Marcos Fernandez***
Affiliation(s):
*cruces University Hospital, **university Of Deusto, ***university Of The Basque Country
Objective: to analyze the prescription of alopurinol and achievement of therapeutic urate levels by different physicians during gout management.
Method: retrospective analysis of a prospective follow-up, nested cohort of patients with gout. From COVID pandemia (2022) data are retrieved from both patients who are followed-up at a hospital-based gout-devoted-office (GO) and patients who are visited at hospital (emergency, in-hospital, hospital general office) but referred to other physicians for further follow-up. Only patients on an alopurinol prescription are selected for analysis. We compare data (dose, dose corrected by estimated glomerular filtration rate, adherence, and rate of target serum urate target achievement) from the GO with those of other prescriptions (OP= family physicians, ambulatory rheumatology, nephrology), as other urate-lowering medications (febuxostat, uricosurics, combination) were seldomly prescribed out of the GO.
Results: 423 patients were recruited from 2nd January 2022 to 31st December 2025. 323/423 (76.3%) had any prescription of any urate-lowering medication: 201/217 (92.6%) and 122/211 (57,8%) in GO and OP setting, respectively. 237 out of 323 had a prescription of alopurinol, and at least one serum urate measuring after alopurinol prescription: 133/201 (66.2%) and 104/122 (85.2%) in GO and OP, respectively.
There were 88% men, mean age 70±12 years (median 70, 1-80), 21.9% were tophaceous, and 23.6% polyarticular distribution (polyarticular, 29% vs. 15%) and tophaceous gout (28% vs. 15%) were more frequent in the GO than in the OP group. Mean serum urate (sUA) at entrance was 9.1±1.2 mg/dl, and GFRe 60±18 ml/min, no differences between groups of prescription being observed, except for GFR at nephrology.
Table 1 shows the distribution in serum urate strata during a treatment with alopurinol. Total daily doses and doses corrected for ml of estimated glomerular filtration globally and depending on achievement or not of therapeutic sUA target, along with adherence as medication position ratio (MPR) are shown in Table 2.
Limitations: this is a cohort generated at the hospital level, showing overall severe disease, especially for the GO group, and high baseline sUA levels. The number in nephrology prescription is low.
Conclusions: 1.- Urate-lowering treatment is more frequently prescribed in GO tan in OP. 2.- Prescriptions other tan alopurinol are less frequently prescribed in OP. 3.- GO prescribes higher doses and higher doses corrected by renal function, therefore achieving higher rates of sUA in therapeutic target. 4.- Whist facing inadequate therapeutics UA levels, no increase in dosing is observed except for GO, indicating clinical inertia. 4.- Clinical inertia in dosing and lower adherence, along with severe disease, may explain lower rates of therapeutic sUA targets.
