Use of the Gout Impact Scale to Evaluate Quality of Life in Chinese Subjects with Gout: A Cross-Sectional Study

BACKGROUND To use a gout-specific quality of life (QoL) tool, the Gout Impact Scale (GIS), to evaluate characteristics of gout affecting QoL in subjects with gout. MATERIAL AND METHODS In this cross-sectional study, 169 individuals with gout completed the 24-item GIS and a general questionnaire regarding gout characteristics. The reliability and validity of the GIS were verified by Cronbach's a and exploratory factor analysis, respectively. The impact of gout characteristics on the QoL of subjects with gout was assessed by stepwise multiple regression analysis. RESULTS The 169 subjects with gout included 149 (88.2%) men and 20 (11.8%) women, of median age 43 years. The reliability of the GIS was appropriate (0.84-0.90), except for Gout Medication Side Effects (0.69) and Unmet Gout Treatment Need (0.59). Exploratory factor analysis showed that construct validity was acceptable, with a cumulative variance contribution rate of 5 common factors of 70.09% and factor loading >0.5 between each pair of items of the GIS. Univariate analysis showed that male sex was positively correlated with Well-being During Attack (p<0.05), and that source of medical expenses, current cigarette use and drinking were significantly correlated with Unmet Gout Treatment Need (p<0.05 each). A family history of gout, gout flares, and attack frequency were significantly correlated with total GIS, Well-being During Attack, and Gout Concern during Attack (p<0.05 each). Multivariate analysis suggested that history of gouty arthritis, acute attack and attack frequency had a considerable impact on QoL (p<0.05 each). CONCLUSIONS The GIS showed acceptable reliability and validity in identifying associations between poor QoL and gout characteristics.