Race Differences in Anxiety Disorders, Worry, and Social Anxiety: An Examination of the Differential-K Theory in Clinical Psychology

Abstract

Differential-K theory, when applied to the study of anxiety disorders, predicts that slower life history (LH) racial groups exhibit higher levels of trait anxiety and worry, and higher prevalence of anxiety disorders, as both LH and anxiety experiences are future oriented. We predict that slower LH racial groups will exhibit an especially high prevalence of those anxiety disorders in which: (A) A central symptom is excessive worry rather than the anxious emotion only, as worry is an effortful cognitive phenomenon that involves mentally scrutinizing longer-term future threats and solutions; and (B) The central source of concern is social interactions, as the long-term maintenance of social relationships is one of the hallmarks of slow LH. We conducted an extensive search in international databases of scientific publications, with selection criteria chosen to reduce the possible effect of methods variance in the design and language of psychometric instruments and protocols, as well as variance in psychological health services and sociopolitical conditions. In line with the evolutionary hypothesis, Whites exhibited a higher prevalence of worry-related and sociality-related anxiety disorders than African-Americans and Latinos. Self-report data on worry and social anxiety traits further supported the evolutionary hypothesis, with Northeast Asians reporting the highest average scores. Importantly however, Blacks exhibited higher rates of post-traumatic stress disorder, a stressor-related condition, lending partial support to the social psychology hypothesis. We review and discuss racial differences in propensity to seek professional help when experiencing distress, in emotional expression to health care workers, and in the validity of psychometric measures, and conclude they are unlikely explanations for the identified race differences. Future studies that test the evolutionary hypothesis on differences among populations within these broad racial groupings are necessary to further examine the predictive power of this theory.