Prevalence of gout with comorbidity aggregations in southern Taiwan.

Objective: Comorbidity is an important concern for chronic gout patients. We evaluated the relationship between comorbidity profiles and gout in Taiwan aborigines and Taiwanese Han.

Methods: We used the claims data from the Taiwan national health insurance database for 2004 to 2006. Physician-diagnosed gout and comorbidities were coded using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Total sampling from Pingtung County of southern Taiwan included 37,482 aborigines (gout cases, n=3906 and controls, n=33,576) and 37,451 Han (gout cases, n=1115 and controls, n=36,336).

Results: In 2006, the gout prevalences were 10.42% and 2.98% (prevalence ratio [PR]=3.50) in the aborigines and Han general populations, respectively. The prevalences of uric acid nephrolithiasis and tophi were higher in aborigines (0.42% and 0.30%, respectively) than in Han (0.09% and 0.04%, respectively). When stratified by comorbidity status, the prevalences of gout were 4.49% and 27.34% in aborigines and 1.52% and 9.44% in Han (approximate PR=3.00). Similarly, the prevalence ratios of gout in the comorbidity group, compared with the non-comorbidity group, were 6.09 in aborigines and 6.23 in Han. Multivariate odds ratios [ORs] showed that hypercholesterolemia, hyperglyceridemia, essential hypertension and renal insufficiency were the common comorbidities of gout (OR≥1.63); heart failure exerted a significant effect only in aborigines (OR=1.55). For five comorbidity factors, patients with multiple comorbidities had higher gout prevalence (maximum OR=12.90).

Conclusion: Gout prevalence was higher in aborigines, both with and without comorbidities, than in Han. The comorbid diseases and comorbidity aggregations showed a substantial association with gout occurrence in both ethnicities.