The effect of changes in society, economy and public health on the disease burden of neurological, mental and substance use disorders: a global longitudinal study. Issue 1 (October 2019) - Sun, Yankun
Abstract: Background: Globally, neurological, mental, and substance use disorders are the leading causes of disease burden, which has increased substantially from 1997 to 2017, accounting for 16·72% of total years of life with disability (YLDs). However, there are few studies investigating the effects of macro-environment on neuropsychiatric diseases. In this study, we aimed to estimate the effects of changes in society, the economy, and public health on neurological, mental, and substance use disorders at the country level. Methods: For this longitudinal analysis, we obtained social, economic, and public health indicators of all countries in 1990–2015 from the World Bank, including urbanisation, public health expenditure (% of gross domestic product [GDP]), sanitation access, number of physicians, calorie intake, and labour force (the number of people aged ≥15 years who supply labour for the production of goods and services). We calculated the disease burden (YLDs, deaths, and disability-adjusted life-years [DALYs]) using data from the Institute for Health Metrics and Evaluation which were calculated for every 5-year interval from 1990 to 2015. We use multivariable regression analysis, controlling for country-specific demographics and infrastructure, to investigate the relationship between socioeconomic changes and disease burden of neuropsychiatric disorders. Findings: Urbanisation has significantly increased the YLDs of mental disorders globally, but there was no effect on neurological disorders. As the number of labour force increased, it was associated with decreasing number of deaths from neurological disorders; however, its effect on disease burden was not statistically significant. From the public health perspective, with increased access to sanitation, the YLDs and DALYs of mental disorders and the deaths from neurological disorders were significantly decreased. Additionally, calorie intake was negatively correlated with all three aspects of disease burden in neurological disorders and the YLDs of mental disorders. From the perspective of health-care financing, YLDs, deaths, and DALYs of neurological disorders decreased with increased proportion of public health expenditure as share of GDP, whereas there was effect on mental disorders. Deaths from neurological disorders decreased as the physician number increased. Interpretation: With the development of society and the economy, improvement in public health services—which is regarded as protective, particularly in low-income and middle-income countries and represented by increased access of sanitation, calorie intake, and the increased share of public health-care expenditure—will contribute to the decrease of disease burden of neuropsychiatric disorders. However, more attention needs to be paid to urbanisation, which is happening not only in high-income countries but also low-income and middle-income regions, since it might trigger more serious disease burden of mental disorders. Funding: National Natural Science Foundation of China.