Some of the richest countries have the highest rates of depression, new research suggests.
An international team of researchers collected the results of face-to-face interviews of nearly 90,000 people considered representatives of their population. The interviews were conducted in community settings in 18 countries, and the interviewers used a standard diagnostic test from the World Health Organization to assess depression.
In the 10 countries considered high-income, an average of 15% of participants said they’d experienced a depressive episode in their lifetime. France, the Netherlands, New Zealand and the U.S. all had rates higher than 18%.
But among the eight low- to middle-income countries surveyed, the rate was 11% -- the lowest rates were found in India, Mexico, China and South Africa.
The research was published Tuesday in the journal BMC Medicine.
The authors acknowledge that language barriers, difficulty in recalling the past and reluctance to be open with a foreign interviewer make it difficult to directly compare results between countries. They also acknowledge that by another measure of assessment, the depressive episodes from the previous year, the rates are fairly similar.
Nevertheless they seem perplexed by the higher overall rates of depression, speculating that perhaps rich nations have more stressful environments, or that the gap between rich and poor is large in affluent countries.
They write in the paper’s discussion:
“On one level, it seems counterintuitive that people in high-income countries should experience more stress than those in low- to middle-income countries. However, it has been suggested that depression is to some extent an illness of affluence.”
More research is needed into the social conditions that are related to depression, they conclude.
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