One would think that people with few friends and living in poverty are more at risk for PTSD than those with a strong support network and many resources.

And that’s true.

However, it is a different story when you look at the country-, rather than the individual level. Countries with more resources, such as the USA and the Netherlands, have higher levels of PTSD than countries with fewer resources (e.g. Colombia, South Africa).

This is the key finding of our latest study, which has just been published in the British Journal of Psychiatry. For the analyses, we made use of international data on trauma exposure, PTSD and country vulnerability. They had been collected in 24 different studies, published between 2005 and 2014.

The information on exposure and PTSD came from one, well-established and (evidently) widely used measure, the Composite International Diagnostic Interview. The country resources, or vulnerability, information came from the annual World Risk Report. It includes a mix of country characteristics, such as number of hospital beds, malnutrition, and gross domestic product per capita.

Both trauma exposure and vulnerability were major determinants of PTSD, but the latter in an unexpected way. While a higher percentage of trauma exposure in the country related to higher levels of PTSD, more vulnerability was associated with less PTSD.

Michel Dückers, the lead author of the study, calls it the “vulnerability paradox”.

Our findings regarding the association with country resources were the opposite of what we had predicted. One explanation may be that vulnerable countries are the ones with stronger social capital. Another explanation might be that general expectations of life are higher in countries with lots of resources and possibilities; when something bad happens future expectations may all get shattered.

These results serve to spark a conversation: what do these data really mean? Is there an artefact that could explain the outcomes? We know that while posttraumatic stress occurs cross-cultures, there are important differences and most of all, there is still a lot we do not know about mental health in a global perspective.

To start with, it may be too optimistic to think that one measure can be applied across all, despite initial cross-cultural validation. Cultural variation in answer tendencies, stigma with regard to reporting problems, and language issues may also have affected the data.

Nevertheless, these are the best data that we currently have to compare posttraumatic mental health across countries. We tried to confirm our findings by looking at data on a different mental health problem, mood disorder, and by looking at smaller datasets that used other measures. They yielded similar patterns.

The findings are an important reminder of the potentially large differences between our countries, not only in terms of resources but also in terms of populations’ mental health and responses to adversity.

The last word certainly has not yet been said about this study and the data, but for me they convey that we need to be very careful with any expectations that we have about how a country’s population as a collective is dealing with disaster and other trauma. There are important lessons to learn from those countries that came up as resilient in our study, irrespective of whether these lessons turn out to be about coping or about answer tendencies to mental health assessment. This vulnerability paradox gives some food for thought…

Reference:

Dückers ML, Alisic E, & Brewin CR (2016). A vulnerability paradox in the cross-national prevalence of post-traumatic stress disorder. The British Journal of Psychiatry PMID: 27445357

Image by New Zealand Defence Force from Wellington, New Zealand – CHCH City – Streets1, CC BY 2.0