A Paradox in Individual Versus National Mental Health Vulnerability : Are Higher Resource Levels Associated With Higher Disorder Prevalence ?

An earlier study (Dückers, Alisic, & Brewin, 2016) found that countries with greater social and economic resources were characterized by a higher lifetime prevalence of posttraumatic stress disorder (PTSD). Here, we present a similar analysis of national population survey data to examine this vulnerability paradox in relation to other disorders. We predicted the lifetime prevalence of any mental health disorder (i.e., anxiety, mood, substance, and externalizing disorders) in 17 countries based on trauma exposure and country vulnerability data. A substantial proportion of variance in all disorder categories, 32.9% to 53.9%, could be explained by trauma exposure. Explained variance increased by 5 and up to 40 percentage points after adding the variable of vulnerability to the equation. Higher exposure and lower vulnerability levels were accompanied by a higher prevalence in any mental disorder, with the largest effect size in mood disorders (R 2 = .76). The interaction between exposure and vulnerability did not explain significant additional variance as it did for PTSD. Because a PTSD diagnosis links psychological, physical, and functional symptoms explicitly to trauma exposure, this might mean that populations in less-vulnerable countries are more likely to attribute health complaints to exposure. The results of this study suggest that country-level data can help to better explain the multilayered mechanisms of resilience and vulnerability in the context of trauma. Resilience and vulnerability are popular concepts in many contemporary branches of policy, research, and practice. Numerous definitions have been formulated, with analyses variously at the levels of individuals, communities, and systems (Olsson, Duckers, M.L., Brewin, C.R. A paradox in individual versus national mental health vulnerability: are higher resource levels associated with higher disorder prevalence? Journal of Traumatic Stress: 2016, 29(6), 572-576 This is a NIVEL certified Post Print, more info at http://www.nivel. eu Jerneck, Thoren, Persson, & O'Byrne, 2015). Mental health research typically focuses on the presence or absence of potential individual or public problems, their development through time, and the role of risk and protective factors (Bonanno, Brewin, Kaniasty, & La Greca, 2010; Brewin, Andrews, & Valentine, 2000). Although resilience and vulnerability have been depicted as layered constructs (Bryant, 2015; Cicchetti, 2010), the study of interactions between different levels of analysis is only beginning, and the national-level aspects are poorly understood. Of relevance here is that we recently identified a “vulnerability paradox”—a counterintuitive association between mental health and the resources of countries measured using a broad collection of socioeconomic datasets (Dückers, Alisic, & Brewin, 2016). We predicted the lifetime prevalence of posttraumatic stress disorder (PTSD) in different countries using data from the World Risk Index (Welle & Birkmann, 2015) capturing countries’ overall cultural and socioeconomic vulnerability to adversity in one index. Although at an individual level the possession of greater resources is protective against PTSD (Brewin et al., 2000), we found that countries with greater wealth and equality, better health care and education, and longer life expectancy are characterized by a higher lifetime prevalence of PTSD (Dückers et al., 2016). In this article, we present a similar analysis of national population survey data to verify whether the vulnerability paradox is apparent for other disorders. METHOD Our secondary analysis is based on data derived from a combination of earlier studies, depending heavily on the heritage of the World Health Organization (WHO) World Mental Health Surveys. Kessler and colleagues (2009) presented the lifetime prevalence of any anxiety disorder (AAD; including agoraphobia, adult separation anxiety disorder, generalized anxiety disorder, panic disorder, PTSD, social phobia, and specific phobia), any mood disorder (AMD; including bipolar disorders, dysthymia, and major depressive disorder), any substance disorder (ASD; including alcohol or drug abuse with or without dependence), and any externalizing disorder (AED; including attention-deficit/hyperactivity disorder, oppositional-defiant disorder, conduct disorder, and intermittent explosive disorder) in the populations of 17 countries based on the WHO Composite International Diagnostic Interview (CIDI; Kessler et al., 2009; the background, methodology, and other findings from the WHO World Mental Health Surveys are described in Kessler and Üstün, 2008). The prevalence data, including the lifetime prevalence of any disorder (AD), are shown in Table 1. [TABLE 1] Lifetime trauma exposure rates were available from another study (Benjet et al., 2016). Benjet and colleagues (2016) reported the prevalence of trauma exposure associated with a number of forms of violence, including collective violence (e.g., being a civilian in a war zone, relief worker in a war zone, refugee), causing or witnessing serious bodily harm to others (e.g., purposely injuring, torturing, or killing someone; combat experience), interpersonal violence (e.g., beaten up by a caregiver as a child, witnessed physical fights at home as a child, beaten up by someone other than a romantic partner), intimate partner or sexual violence (e.g., physically assaulted by a romantic partner, raped, sexually assaulted), accidents and Duckers, M.L. , Brewin, C.R. A paradox in individual versus national mental health vulnerability: are higher resource levels associated with higher disorder prevalence? Journal of Traumatic Stress: 2016, 29(6), 572-576 This is a NIVEL certified Post Print, more info at http://www.nivel. eu injuries (e.g., natural disasters, automobile accidents), unexpected death of a loved one, mugged, or threatened with a weapon, and manmade disaster (Benjet et al., 2016). Vulnerability data for the 17 countries were taken from the World Risk Report of 2015 (Welle & Birkmann, 2015). The vulnerability of 171 countries was summarized using 23 indicators, divided into three components, and measured using worldwide and publicly accessible data. Susceptibility describes a country's structural characteristics and conditions that can sustain harm. For example, indicators of susceptibility involve malnutrition, access to sanitation, income equality, and gross domestic product per capita. Lack of coping capacity refers to the inability of a country to minimize negative impacts of events and includes indicators such as number of physicians and hospital beds per 10,000 inhabitants and level of public sector corruption. Lack of adaptive capacities refers to conditions that fail to support long-term, structural change. Example indicators include the adult literacy rate, combined gross school enrollment, forest management, and public and private health expenditure. Country vulnerability scores are calculated on a scale, ranging theoretically from 0 (minimum) to 100 (maximum), and can be interpreted as percentage values. More background information on the vulnerability index, its composition, and analysis can be found in the World Risk Report (Welle & Birkmann, 2015). Data Analysis We calculated correlation coefficients and tested three linear regression models with the lifetime prevalence of the disorders treated as dependent variables. In the first model, exposure was entered as predictor, followed by the second model including exposure and vulnerability, and the third model including an interaction term to test whether a country's level of vulnerability moderated the relation between exposure and the disorders. We defined effect sizes as small (r ≤ .1), medium (r ≤ .3), large (r ≤ .5), or very large (r ≤ .7; Rosenthal, 1996). All analyses were performed using IBM SPSS Statistics (Version 20) and G*Power (Version 3.0.10). RESULTS After we examined the data for outliers, we excluded the lifetime prevalence of AAD and AED in the United States (which were 31% and 25%, respectively). Distributional information for the variables and the correlations between them are shown in Table 2. Trauma exposure correlated significantly and positively with rates of AAD (r = .57), AMD (r = .60), ASD (r = .64), AED (r = .70), and AD (r = .73), all with large to very large effect sizes. In line with the paradox, the correlations between country vulnerability and rates of mental disorders were all negative in sign. Effect sizes varied from small (AAD and ASD), to medium (AD), and large (AMD). Only the correlation between vulnerability and AMD was significant. [TABEL 2] The regression analyses (see Table 3) confirmed that trauma exposure explained a significant proportion of variance in all mental health disorders (R 2 ranged from 33% to 54%: Model 1). After adding vulnerability in Model 2, the level of variance explained increased from 5 up to 40 percentage points. An increase in vulnerability had a significant negative effect on the predicted prevalence for AD (β = −.43) and Duckers, M.L. , Brewin, C.R. A paradox in individual versus national mental health vulnerability: are higher resource levels associated with higher disorder prevalence? Journal of Traumatic Stress: 2016, 29(6), 572-576 This is a NIVEL certified Post Print, more info at http://www.nivel. eu AMD (β = −.64). The interaction between exposure and vulnerability—which led to a better-fitting model in previous research concerning the prediction of PTSD (Dückers et al., 2016)—did not explain significant additional variance in the present data in AAD, AMD, ASD, AED, or AD (Model 3).