Changes in health inequalities for patients with diabetes among middle-aged and elderly in China from 2011 to 2015

BACKGROUND: The purpose of this paper is to measure income-related health inequality among middle-aged and elderly patients with diabetes in China from 2011 to 2015 and to investigate factors that might be related to this inequality. METHODS: The data for this study were obtained from the China Health and Retirement Longitudinal Study that was carried out in 2011, 2013 and 2015. In total, 48,519 Chinese middle-aged and elderly population were included (15,457 in 2011, 16,576 in 2013 and 16,486 in 2015). A principal component analysis was performed to measure asset-based economic status. The concentration index was used to measure income-related inequality in patients with diabetes. Additionally, by used generalized linear model, we decomposed the concentration index to identify factors that explained wealth-related inequality in patients with diabetes. RESULTS: The prevalence of self-reported diabetes among middle-aged and elderly Chinese was 5.61, 7.49 and 8.99% in 2011, 2013 and 2015, respectively. The concentration indices and 95% confidence intervals for diabetes were 0.1359 (0.0525–0.0597), 0.1207 (0.0709–0.0789), 0.1021 (0.0855–0.0942) in 2011, 2013, and 2015, respectively, which are indicative of inequality that favors the rich. The decomposition of the concentration index showed that residence (39.38%), BMI (31.16%), education (7.28%), and region (6.09%) had positive contributions to the measured inequality in diabetes in China in 2015. Age (− 29.93%) had a negative contribution to inequality. CONCLUSION: The findings confirm a health inequality in diabetes that favor the rich. Furthermore, the inequality declined from 2011 to 2015. We suggest that policy and intervention strategies should be developed to alleviate this health inequality, such as narrow the gap between urban and rural areas by improving the urban-rural medical insurance scheme, implementing strategies to enhance hygiene health education, control obesity rate.