WASHINGTON — High temperature and humidity seem to increase the risk of recurrent gout attacks independently of other known risk factors, Yuqing Q. Zhang, D.Sc., reported at the annual meeting of the American College of Rheumatology.
“Although the pathophysiology of gout is well understood and efficacious clinical therapies are available, many patients with gout still suffer from recurrent gout attacks” brought on by certain risk factors, said Dr. Zhang of Boston University.
Decreases in intravascular volume from perspiration in hot, humid weather can result in high serum uric acid levels because of a reduction in uric acid excretion, Dr. Zhang said. Few studies have examined the link between risk factors for dehydration and the risk of recurrent gout attacks.
Dr. Zhang and his colleagues enrolled 197 patients with a median 5-year history of gout through an online advertisement. The patients answered a “hazard period” questionnaire on a Web site that asked about risk factors for gout attacks during the 2-day period before reporting an attack. They also filled out a control period questionnaire every 3 months for 1 year to provide data about time intervals between gout attacks. They were asked about medication use (such as diuretics), alcohol use, food intake (especially foods rich in purine or with little purine), and details of gout attacks when they occurred.
Weather information from more than 1,600 U.S. airports was provided by the Weather Underground Web site (www.wunderground.com
The relationship between the level of humidity during the 2 days before a gout attack and the risk of recurrent attacks followed the pattern for temperature very closely. High humidity seemed to be the strongest predictor for recurrent gout attacks, but very cold and dry weather also slightly increased the risk.
The findings were significant after controlling for medication use, alcohol consumption, and purine-rich food intake. Recurrent attacks were not associated with barometric pressure or precipitation.