Gout And Aspirin

Session: Epidemiology and Health Services Research: Novel Research Methods

Presentation: 2039 – Low-dose Aspirin Intake Increases Risk of Recurrent Gout Attacks: The Online Case-crossover Gout Study

Category: 31. Epidemiology and health services research

Author(s): Y. Zhang1, C. Chen1, T. Neogi1, C. Chaisson1, J. Niu1, R. Terkeltaub2, D. Hunter1. 1BUSM, Boston, MA; 2VA Medical Center, San Diego, CA

Abstract: Low-dose aspirin (ASA) is widely used as a public health strategy for preventing heart attacks. However, this clinical practice may have an untoward effect on the control of recurrent gout attacks. ASA is known to have a bimodal effect on renal handling of uric acid. High doses of ASA (>3 g/day) are uricosuric, whereas low doses (< 1 g/day) reduce uric acid excretion. Furthermore, patients with gout may be at higher risk for aspirin-induced adverse effects due to impaired renal function. Despite this, no study has assessed the effect of low-dose ASA on the risk of recurrent gout attacks. Clarification of the effect of low-dose ASA on the risk of recurrent gout attacks would inform guidelines for low-dose ASA use among gout patients.
We conducted a case-crossover study to assess a set of putative risk factors triggering recurrent gout attacks. Subjects who had experienced a gout attack within the past year were recruited online and were asked to provide access to medical records. Subjects logged onto the study website when they experienced a gout attack. Risk factors, including low-dose ASA use (<325 mg/day), occurring each day over the two-day period prior to an acute gout attack (case period) were assessed using an online questionnaire. The same questionnaire was used over each of two days during an intercritical period (control period). We examined the relation of low-dose ASA use over the 2-day period to the risk of recurrent gout attacks using conditional logistic regression adjusting for alcohol consumption, purine intake, and diuretic use among subjects who reported taking low dose ASA to prevent heart attack.
Of 105 (30%) gout patients who reported taking low-dose ASA to prevent heart disease, approximately one-third took low-dose ASA intermittently. Participants were predominantly white (89%) and male (83%), and 58% had a college education. The median time between onset of gout attack and logging on to the website was 6 days. Of the 99 medical records obtained to date, 88% (n=87) fulfilled ACR criteria for a gout diagnosis. The proportion of low-dose ASA use on only one day was 4.6% and on two consecutive days was 57.5%, respectively, during the control periods (n=259). The corresponding proportion was 3.6% and 78.5% during the case periods (n=195). Compared with no use of low-dose ASA over the past two days, the adjusted odds ratio for recurrent gout attacks was 3.9 (95% CI: 2.0-7.3) for using low dose ASA over two consecutive days prior to their gout attacks; no increased risk was observed if subjects used low-dose ASA for only one day over the past 2 days (OR=1.3, 95% CI: 0.3-6.3).
In conclusion, we found that low-dose ASA use in consecutive 2 days increased the risk of recurrent gout attacks among gout patients and this should be considered when weighing gout and heart disease prevention in individual patients.
Research Method: Observational

Also see aspirin on the gout blog.