Recent diuretic use and the risk of recurrent gout attacks: the online case-crossover gout study.

OBJECTIVE To assess several putative risk factors, including thiazide and loop diuretics use, thought to trigger recurrent gout attacks. METHODS We conducted an internet-based case-crossover study involving subjects who had a gout attack within the past year. Patients were recruited online and asked to provide access to medical records. Data were obtained on specific diuretic use on each day over the 2-day period prior to an acute gout attack (hazard period) and on each day of 2 days during the intercritical period (control period). We examined the relation of all diuretic use and use of specific diuretics, i.e., thiazide and loop, to the risk of recurrent gout attacks using a conditional logistic regression model adjusting for alcohol consumption and purine intake. RESULTS One hundred ninety-seven subjects completed both control and hazard period questionnaires. Participants were predominantly male (80%) and over half had a college education. The median time between onset of gout attack and logging on to the website was 2 days. Adjusting for alcohol consumption and purine intake, the odds ratio (OR) for recurrent gout attacks from all diuretic use over the last 48 h was 3.6 (95% confidence interval 1.4-9.7). OR of recurrent gout attacks were 3.2 and 3.8 for use of thiazide and loop, respectively. CONCLUSION Recent use of diuretics is associated with a significantly increased risk for recurrent gouty arthritis. The increased risk of gout attacks from either thiazide or possibly loop diuretic therapies represents an important modifiable risk factor in patients with gout.