Risk of gout attack not increased in patients with thalassemia: a population-based cohort study

The incidence of gout arthritis in patients with thalassemia and the association between them was indefinite. We aimed to give epidemiological evidence regarding the association between thalassemia and gout arthritis. This retrospective cohort study extracted data relating to the risk of gout arthritis from patients diagnosed with thalassemia between 2000 and 2013. We selected the control group at a ratio of 1:4 by propensity score matching (PSM). Univariable and multivariable Cox proportional hazard regression models were performed to analyze the association between thalassemia and gout arthritis and to evaluate the hazard ratio (HR) of gout arthritis after exposure with thalassemia. The sensitivity analysis was performed to avoid the mislabeled thalassemia disease, the transfusion-dependent thalassemia was classified to compare the risk of gout arthritis. The secondary outcome for the risk of gout arthritis with antigout drugs treatment was also evaluated between study groups. In the age and sex matched cohort, the majority of thalassemia patients were women (62.03%) and aged younger than 30 years old (44.79%). There were 138 (4.2%) and 500 (3.8%) incident cases of gout arthritis in the thalassemia and non-thalassemia group. After PSM, the incidence rate, per 100 person-years, of gout arthritis was 0.48 (95% CI 0.42 to 0.56) and 0.60 (95% CI 0.51 to 0.72) in non-thalassemia individuals and patients with thalassemia, respectively. In the Cox proportional hazard regression, patients with thalassemia had no significant increase in the risk of gout arthritis (adjusted HR, 1.00; 95%CI: 0.80 to 1.25) after adjusting demographic variables and comorbidities. The Kaplan-Meier curve showed that the cumulative incidence of gout arthritis was not a significant difference in the thalassemia group than in the comparison group (p > 0.05). The sensitivity analysis showed the consistent results about the risk of gout arthritis in patients with thalassemia. Our study indicated that there was no significant increase in the risk of gout arthritis in subjects with thalassemia.Future research needs to clarify the biological mechanisms behind this connection.