The research named open-access journal BMC Medicine, studied depression rates in 18 countries worldwide. It conceived that the average lifetime prevalence of major depression in the 10 high-income countries in the study was 14.6 percent. In the eight low- and middle-income countries, the lifetime prevalence of major depression was 11.1 percent.
The study linked depression with social factors such as age, marital status and income. Wealthier countries were found to experience more depression because they had more of income inequality. The World Health Organization (WHO) says that depression which results in suicide causes 850,000 deaths per year.
The countries surveyed included: (high income countries) Belgium, France, Germany, Italy, Japan, the Netherlands, New Zealand, Spain and the United States, and (low income) countries were: Brazil, Colombia, India, China, Lebanon, Mexico, South Africa and Ukraine.
Questions included in the survey were about age, income and marital status. Major depression symptoms, including sadness and loss of interest in daily life were also focused.
The results of the study showed that the wealthier countries had higher depression rates than the poor countries.
Marital status and income-inequalities were found to be the major reasons for depression. The study also found that women were twice as likely prone to depression than men in any part of the world.