Gout: Overview and Risk Factors  

Gout is a metabolic disease characterized by hyperuricemia and precipitation and tissue deposition of urate crystals, resulting in inflammation and tissue injury.  Clinical manifestations include recurrent bouts of acute, often monoarticular arthritis, which most commonly affects the first metatarsophalangeal joint (“podagra”), knees, ankles, and wrists; nephrolithiasis; and palpable tophi. 

Ninety percent of cases are due to decreased excretion of uric acid, usually secondary to chronic renal disease, low volume states, and diuretic use. The remaining 10% are due to excess uric acid production, as may occur in the context of inherited enzyme abnormalities, psoriasis, hemoglobinopathies, and leukemias. Not all patients with hyperuricemia will develop gout. Indeed, about two–thirds of hyperuricemic patients will remain asymptomatic. Higher levels of serum uric acid and longer durations of exposure increase the risk of progression to clinical disease. However, some patients with clinical symptoms of gout have normal serum uric acid levels.   

Risk Factors

• Age. Incidence increases with age. 
• Gender. In younger populations, gout occurs more commonly in males, presumably because estrogen facilitates urinary excretion of urate in women. Gender does not affect risk in older patients.
• Family history.
• Dietary factors. See Nutritional Considerations below. 
• Obesity.
• Medication. Diuretics, cyclosporine, aspirin, and niacin increase serum uric acid levels.
• Stress, trauma, surgery. These factors may precipitate acute attacks.