Nighttime gout attack risk may be twice as much as in daytime

The risk of acute gout attacks was more than twice as high during the night or early morning hours than the day, even among those who did not consume alcohol and had a low purine intake during the 24 hours prior to the attack, a study found.

Researchers recruited 724 gout patients for The Boston Online Gout Study, a case-crossover study that investigated triggers for gout attacks from 2003 to 2013. Patients were followed online for 1 year to track the date and hour of gout attacks, as well as symptoms, medication use, and risk factors such as alcohol use and seafood consumption during the 24- and 48-hour time periods preceding flare-ups.

Results appeared online Dec. 11 at Arthritis & Rheumatology.

Overall, roughly 68% of subjects consumed alcohol, 29% took diuretics, 45% used allopurinol, 54% used nonsteroidal anti-inflammatory drugs (NSAIDs), and 26% took colchicine.

Participants experienced 1,433 gout attacks: 733 in the overnight hours (12 a.m. to 7:59 a.m.), 310 in the daytime (8 a.m. to 2:59 p.m.), and 390 in the evening (3 p.m. to 11:59 p.m.) during the 1-year study period. The risk of gout flares was higher overnight than in the daytime (odds ratio [OR], 2.36; 95% CI, 2.05 to 2.73). The OR in the evening compared to daytime was 1.26 (95% CI, 1.07 to 1.48). These associations persisted among those with no alcohol use and in the lowest quintile of purine intake in the 24 hours prior to attack onset, as well as in subgroups according to diuretic use and use of allopurinol, colchicine, and NSAIDs during the 24 hours prior to attacks and according to sex, age group, and obesity status.

Prophylactic measures that prevent gout flares, especially at night, may be effective, the authors noted. “[O]ur study findings provide the first prospective evidence that the risk of gout attacks during the night and early morning is approximately three times higher than in the daytime. These data support the purported mechanisms and historical descriptions of the nocturnal onset of gout attacks and may have implications for anti-gout prophylactic measures.”