Avoiding sugar-sweetened drinks may be particularly important for people with a high BMI in order to reduce the risk of hyperuricaemia and gout, an analysis of three large databases has concluded.

Rheumatologist Professor Nicola Dalbeth, from the University of Auckland, and colleagues found that drinking two or more sugar-sweetened beverages a day significantly increased the likelihood of elevated serum urate and increased the risk of gout by 33%, but only in people with had a BMI of 25 or more.

The findings on were based on more than 12,000 participants in the Atherosclerosis Risk in Communities Study, the Framingham Heart Study and a New Zealand dataset, and reported in Arthritis Research and Therapy.

Professor Dalbeth and her colleagues also examined the acute responses to drinking a fructose solution in 76 healthy volunteers.

Serum urate levels were higher at baseline and throughout the three-hour observation period in volunteers with a high BMI but the responses to the load were similar to that in lean volunteers.

However, fractional excretion of uric acid was reduced and renal clearance slower in those with high BMI, indicating altered handling of urate by renal tubules in the presence of both obesity and an acute sugar load.

Minimising the risk of elevated serum urate and gout should be added to the many other health benefits of avoiding sugary drinks, Professor Dalbeth said.

“The effect of sugar-sweetened beverage intake on serum urate has been attributed to the hepatic effects of fructose on ATP degradation, which in turn, induces urate production.

“Sugar may also directly interfere with urate excretion via the hexose-uric acid transporter solute carrier family 2, facilitated glucose transporter member 9 (SLC2A9).”

Although sugary drinks had clearly been identified as a strong modifiable risk factor for gout, the interactions with BMI had not been fully explored.