Profiling Psychopathology in a Unique Population Chronically Ill Adults: A Dimensional Approach

The internalizing and externalizing dimensions of psychopathology have been shown to effectively identify groups that are at higher risk for experiencing certain forms of psychopathology. Many studies have shown that chronic physical health conditions are a risk factor for psychological distress, yet there has been very little research examining the association between chronic physical health conditions and dimensional models of psychopathology to date. In the present study we examined the factor structure of internalizing and externalizing symptoms in a sample of adults with postural orthostatic tachycardia syndrome (POTS; n =172) and in a sample of adults without any chronic illness diagnoses (n = 199). Confirmatory factor analyses suggested that psychological distress in individuals with POTS can be effectively characterized by an internalizing dimension composed of distress and fear subcomponents as well as an externalizing dimension. Tests of measurement invariance allowed for the examination of latent means, which showed that individuals with POTS tend to have higher scores on the internalizing dimension and lower scores on the externalizing dimension than healthy controls. Regression analyses suggested that within the sample of people with POTS, those who were more accepting of their illness and had higher health related quality of life tended to have lower scores on the internalizing dimension. Findings suggest that individuals with POTS are at heightened risk for experiencing internalizing symptoms of psychopathology. A dimensional conceptualization of psychopathology seems like an effective way to identify symptoms of psychopathology that are separate from symptoms of autonomic nervous system dysfunction.