Sex Difference in the Association between Education and Schizophrenia in Chinese Adults

Objective: Improving education level was evidenced to decrease the risk of schizophrenia, but whether this strength of education role depends on gender is not. This study aimed to investigate whether there is sex difference in the association between education and schizophrenia in Chinese adults. Methods: Data was obtained from the Second China National Sample Survey on Disability in 2006, and restricted our analysis to 1,909,205 participants aged 18 years or older, which covered 31 provinces (administrative districts) in China. Schizophrenia was ascertained according to the International Statistical Classification of Diseases, Tenth Revision. Logistics regression models was fitted to examine the combined effect of sex and education on schizophrenia. Results: The prevalence of schizophrenia in female groups was higher than in male groups, with 0.44% (95%CI: 0.42%, 0.45%) and 0.36% (95%CI: 0.35%, 0.37%), respectively. There is a statistical significant difference that more females experienced severe or extreme difficulty in understanding and communicating. However, more males suffered from severe or extreme difficulty in the function of daily activities and participation in society. The combined effect of education and schizophrenia was statistically significant (OR=1.05, 95%CI=1.02, 1.08), indicating that, as the level of education level increased, schizophrenia risk of females decreased faster than the risk of males. Conclusions: This study showed that additional years of education reduce the risk of schizophrenia for both men and women while also closing the gender gap between them. As education elevated, the risk of schizophrenia decreased more for women than for men. The findings indicated that improving education level may have an effect on reducing gender gaps in schizophrenia in China. Action to prevent schizophrenia and close its gender gap will require attention to the improving educational opportunities. Funding Statement: This work was supported by the State Key Funds of Social Science Project of China (Grant No. 09&ZD072), National Natural Science Foundation of China (Grant No. 71661167003), Changjiang Scholar Incentive Program of Ministry of Education. Declaration of Interests: The authors declare no potential conflicts of interest with respect to the authorship and/or publication of this article. Ethics Approval Statement: The survey was conducted in all provinces by the Leading Group of the National Sample Survey on Disability and the National Bureau of Statistics with approval by the State Council of China. All survey respondents provided consent to the Chinese government.