The changing epidemiology of gout.

Gout is one of the most common inflammatory arthritides, which is considered to be a true crystal deposition disorder caused by the formation of monosodium urate crystals in and around joints. A number of epidemiological studies from a diverse range of countries suggest that gout has increased in prevalence and incidence in recent years and that the clinical pattern of gout is becoming more complex. In particular, the greatest increase has been observed in primary gout in older men. Robust epidemiological studies have established risk factors for gout including genetic factors, excess alcohol consumption, purine-rich diet, the metabolic syndrome (obesity, hypertension, hyperlipidemia and insulin resistance), use of diuretics and chronic renal failure. Trends in alcohol use, diet, obesity and the metabolic syndrome in the general population might explain changes in the prevalence and incidence of gout in the community. Osteoarthritis, which is thought to predispose patients to monosodium urate crystal deposition in their joints, is becoming more prevalent as a consequence of increased longevity. In hospital settings, widespread diuretic use, increasing prevalence of end-stage renal failure and the success of organ transplant programmes have led to an increase in clinical complexity. Suboptimal management of gout is likely to have contributed to the rise in the prevalence of clinically overt, symptomatic, chronic gout.