Increased risk of cancer among gout patients: a nationwide population study.

OBJECTIVE

Few studies have investigated the association between gout and cancer. The present study examined the relative risk of cancer in a nationwide cohort.

METHODS

The primary data source was the National Health Insurance database of Taiwan. Data recorded between 2000 and 2008 for subjects ≥20 years and with no history of malignancy were included for the analysis. A gout case definition was defined by records of gout diagnosis and anti-gout treatment (urate-lowering drugs, including allopurinol, benzbromazone, probenacid and sulfinpyrazone, and colchicine). Cox proportional hazards models were used to examine the association between gout and cancer.

RESULTS

A total of 694,361 patients (355,278 men, 339,083 women) were included; among them, 25,943 had a history of gout. Mean age (±standard deviation) was 42.3±16.3 years. During 5,471,272 patient-years of follow-up, cancer was detected in 24,088 patients (1745 with gout and 22,343 controls). The most cancers were liver, lung, and colonic cancers. The overall incidence of cancer was significantly higher among gout patients than controls (8.7 vs. 4.2 cases per 1000 patient-years, P<0.001). After adjustment for age and sex, gout was found to be associated with a hazard ratio (HR) of 1.15 (95% confidence interval [CI], 1.10-1.21; P<0.001) for cancer. Gout was most closely associated with prostate cancer, with an age- and sex-adjusted HR of 1.71 (1.45-2.02). On the other hand, gout tended to have an inverse, albeit insignificant, association with breast cancer (adjusted HR, 0.81; 95% CI, 0.63-1.04).

CONCLUSIONS

Gout was associated with increased risk of cancer, particularly that of prostate cancer in males.