Extension of the hierarchical model of anxiety and depression to the personality domain [thesis]

Roman I Kotov
Research on the empirical structure of distress (mood and anxiety) disorders has yielded many valuable insights. These efforts have culminated in the integrative hierarchical model (Mineka, Watson, & Clark, 1998) , which specified general, specific, and unique components of distress disorders. However, some components have not yet been identified, and the model cannot account for temporal relations among the syndromes. Clark, Watson, and Mineka (1994) suggested that personality traits may help
more » ... ty traits may help us fill these gaps. Accordingly, I proposed a hierarchical-vulnerability model of distress disorders, which posits that psychiatric syndromes are products of interactions between personality traits and environmental stressors. This model is patterned after the integrative hierarchical model, as it specifies various levels of generality among personalitypsychopathology links. The aim of this study was to develop the personality component of the model by identifying traits relevant to four target syndromes: major depression, panic disorder, social phobia, and OCD. Building on previous research, I hypothesized several trait contributors for each of the disorders. On the other hand, the traits consistently accounted for 75% of the covariance among the syndromes. In sum, the hierarchical-vulnerability model offers a useful approach to conceptualizing personality-psychopathology relations. However, the stress component of the model is yet to be developed. Furthermore, the present findings need to be replicated in new samples and evaluated in longitudinal studies. Finally, the model needs to be extended to include other disorders and traits. Abstract Approved: ____________________________________ Thesis Supervisor ____________________________________ ACKNOWLEDGMENTS This dissertation was very much a collaborative project. Many people made critical contributions to the study, and it would not have been possible without them. First, I want to thank my advisor, David Watson. It is remarkable that he allowed me to undertake a project of this scope. This freedom has been characteristic of David's mentorship, and I have greatly benefited from it. In fact, this ability to do "my own thing" has been the single best thing about my graduate school experience. Importantly, David did not just let me "sink or swim" but supported this project every step of the way: providing the funding, facilitating access to patient population, supporting recruitment of research assistants, giving timely and thorough advice on matters that ranged from study design to layout of fliers, as well as making every effort to ensure that the thesis was ready for a successful defense. These are just a few of David's many contributions. His mentorship has been extraordinary. Lee Anna Clark provided invaluable help to me with this project and many other endeavors. She played a central role in securing funding, gave a thorough review to various drafts of the thesis (as well as numerous other papers), promptly answered my questions, and wrote many recommendation letters on my behalf. Lee Anna's contributions to my training are remarkable; during my five years at Iowa there was not a semester that I did not attend her lab meetings, and the most important lessons learned concerned ethics, professionalism, and rigorous conduct of research. She truly is my second mentor. The other committee members, Mike O'Hara, Jim Marchman, and Don Black, have consistently surpassed my expectations and made many important contributions of their own. To mention just a few, Mike's support was critical for successful patient recruitment, and his willingness to share his lab space with our team made an enormous difference. Jim's permission to run sessions at the department clinic solved many logistic ii problems and was deeply appreciated. More importantly, Jim contributed tremendously to my clinical training, and this knowledge continues to inform and influence my research in many important ways. I very much appreciated Don's consultation on this and several other studies. I am still amazed at the attention and interest he gave me (a first year graduate student) the first time I showed-up in his office with a far-fetched idea of an epidemiologic study in Russia. The extent of data collection required for this project was far beyond my resources. Luckily, I had help with day-to-day running of the study from many dedicated individuals. Wakiza Gamez has been an amazing collaborator. He took charge of designing the interview and was closely involved in every aspect of interviewing: training, revisions, analyses, and write-ups, not to mention his many contributions to other aspects of the study. Jenny Gringer Richards was our key recruiter. She singlehandedly delivered the patient sample. The greatest thanks are due to our unparallel team of research assistants. They worked unpaid for many hours a week year-round in the face of formidable challenges and frequent set-backs. More was expected from them than just about any undergraduate research assistant, and they rose to these demands. Every member of the team showed rare dedication, but true leaders among them were Micah Wolen. Last but not least, I want to mention help and support of Stephanie Hart. Although, her contributions were indirect, I could not overestimate their importance. This project would not have gotten this far without her support. iii ABSTRACT Research on the empirical structure of distress (mood and anxiety) disorders has yielded many valuable insights. These efforts have culminated in the integrative hierarchical model (Mineka, Watson, & Clark, 1998), which specified general, specific, and unique components of distress disorders. However, some components have not yet been identified, and the model cannot account for temporal relations among the syndromes. Clark, Watson, and Mineka (1994) suggested that personality traits may help us fill these gaps. Accordingly, I proposed a hierarchical-vulnerability model of distress disorders, which posits that psychiatric syndromes are products of interactions between personality traits and environmental stressors. This model is patterned after the integrative hierarchical model, as it specifies various levels of generality among personalitypsychopathology links. The aim of this study was to develop the personality component of the model by identifying traits relevant to four target syndromes: major depression, panic disorder, social phobia, and OCD. Building on previous research, I hypothesized several trait contributors for each of the disorders. I administered an extensive personality battery and an interview measure of the target syndromes to two samples: 385 undergraduates and 188 psychiatric patients. First, I evaluated the associations among the personality measures. Next, I tested study hypotheses using correlational and multiple regression analyses. I also examined the robustness of results across samples. The results confirmed the central role of negative emotionality as the shared trait vulnerability. I also identified two specific trait contributors (linked to two disorders each), and seven unique contributors. Notably, all unique associations involved either depression or social anxiety. The model was able to explain roughly half of variance in these two syndromes but only approximately a quarter of the variance in panic and OCD. iv On the other hand, the traits consistently accounted for 75% of the covariance among the syndromes. In sum, the hierarchical-vulnerability model offers a useful approach to conceptualizing personality-psychopathology relations. However, the stress component of the model is yet to be developed. Furthermore, the present findings need to be replicated in new samples and evaluated in longitudinal studies. Finally, the model needs to be extended to include other disorders and traits.
doi:10.17077/etd.3nmm1ta5 fatcat:bjqdjczrlzfehahbbuoegg2q7y