Fischer, Jamie2024-03-292024-03-292024-02https://hdl.handle.net/11299/262008University of Minnesota Ph.D. dissertation. February 2024. Major: Social Work. Advisor: Patricia Shannon. 1 computer file (PDF); viii, 184 pages.Background: Loneliness has been robustly associated with negative health and wellbeing outcomes and is a growing concern across the United States. Adolescents and people with psychosis spectrum diagnoses have been shown to be at greater risk of experiencing chronic loneliness than the general public. However, loneliness is not well understood within the psychosis spectrum. Research focused on loneliness within psychosis populations has shown that loneliness is strongly correlated with clinical and psychosocial factors of psychosis that are commonly associated with both clinical and functional impairment. However, the current body of research is limited, and many questions remain about the potential causes and consequences of loneliness in both general and early psychosis populations. The three studies included in this dissertation aim to explore and identify causal relations between loneliness and common factors of psychosis in three distinct psychosis populations. Methods: The participants recruited for each of the three studies were categorically different from one another. Participants in the first study were categorized as a general psychosis spectrum sample, while participants in the second study were categorized as an early psychosis spectrum sample. Participants in the third study were categorized as a first-episode psychosis sample and included people with schizophrenia spectrum disorders only. The participants in each of the three studies were also engaged in some form of psychosis intervention. Studies one and two explored data over a six-month period, while study three explored data over a one-year treatment period. Causal discovery methods were used in each of the three studies to identify preliminary causal structures of loneliness across each of three datasets. Each causal analysis was exploratory and uncontrolled. Study one included a more traditional linear mixed model analysis that allowed for a comparison between associational and causal discovery methods. Studies two and three each included post-hoc analyses examining change over time among the variables included in each respective preliminary causal model. Results: The linear mixed model comparison in study one revealed that internalized stigma, self-reported depression, and rater-rated negative symptoms were the strongest predictors of loneliness. However, the preliminary causal model in study one showed that loneliness was the primary cause of loneliness over the six-month period. There were ambiguous relationships between loneliness and self-reported motivation to engage in activities at both baseline and four-months. Loneliness was shown to causally influence internalized stigma, self-reported depression, self-reported social pleasure, and rater-rated motivation at the four-month timepoint. In study two, the preliminary causal model indicated loneliness was a possible cause and consequence of self-reported depression at baseline and six-months; an ambiguous edge was observed between these two variables at baseline. Loneliness was also shown as a possible causal influence of self-rated discrimination experiences at baseline and rater-rated depression at six-months. In the third study, the preliminary causal model indicated that loneliness was the primary cause of loneliness over the year-long period. Internalized stigma was indicated as a possible cause of loneliness at three-months and as a direct causal influence of loneliness at six-months. Loneliness causally influenced both social functioning and recovery attitudes at six-months; loneliness was shown to causally influence social functioning at one year. Conclusions: Overall, several initial patterns were observed across the preliminary causal models. First, loneliness may have a causal relationship with specific types of self-reported motivation. Second, loneliness may have stronger causal relations with self-reported versus rater-rated clinical or functional measures. Third, loneliness may not be a primary consequence of typical psychosis treatment targets, but loneliness may have a causal influence on common psychosis treatment targets. Fourth, loneliness did not appear to change along with its known clinical or functional correlates in the context of research or clinical intervention. Fifth, loneliness appeared to be largely self-sustaining. And lastly, causal relations were detected between loneliness and internalized stigma/perceived discrimination across all three studies. While current clinical intervention paradigms do not typically include loneliness as a treatment target, the overall patterns detected across these three studies suggest the following implications for clinical practice. Loneliness should be assessed at baseline and monitored throughout the course of treatment for those enrolled in clinical programs. Cognitive interventions and coordinated specialty care did not appear to have a large impact on loneliness or internalized stigma/perceived discrimination during the analysis periods. Additional intervention approaches are likely needed to address loneliness for those enrolled in traditional or coordinated-specialty care.enThesis or Dissertation