Generic and disease-specific mechanisms of persistence of somatic symptoms in various diseases
The mechanism of development of persistent somatic symptoms (PSS) is considered to be multifactorial, with biological, psychological, and social factors playing a role. While some risk factors and putative mechanisms for PSS have been identified in somatoform disorders and functional syndromes, corresponding studies for somatic diseases are almost completely lacking. So far, isolated questions have been investigated, e.g., what psychosocial risk factors exist and what role do expectancies play. However, the heterogeneity of the data of previous studies makes it difficult to formulate consistent hypotheses on cross-disease risk factors and mechanisms. Therefore, there is a need for comparable, standardized, high-quality data and analyses across different diseases and syndromes to consistently assess which factors are generic and which are specific to particular diseases.
The overall objective of the SOMA.STATS project is to enable high-quality analyses, data synthesis, and comparisons across projects by creating an overarching structure that takes into account the content and design of all projects in the SOMACROSS research group. The SOMA.STATS project will allow the creation of a comprehensive structural equation model (SEM) for PSS based on the research group's working model. This model will describe both disease-specific and common risk factors and their interaction and will allow the development of a prognostic model and associated risk score.
The SOMA.STATS project will compile prospectively collected data from the core data set of individual projects 1 through 5 from nine different diseases using the core instruments collected at three identical time points (baseline, 6- and 12-month follow-up) into a database that will be created, managed, and maintained by the SOMA.STATS project (total sample N=1264). The data collection processes will be managed and supervised by the SOMA-Stats project. Because a large number of variables are considered relevant to PSS and the interactions are likely to be complex, a longitudinal SEM for PSS in different diseases and syndromes will be created. In addition, the SOMA.STATS project will provide methodological support and in-terdisciplinary toolboxes related to methodology, measurement time points, core instruments, and target variables across all projects.
The SOMA.STATS project will provide infrastructure to support interdisciplinary research and ensure high methodological standards and comparability for all projects. Expected outcomes of the SOMA-Stats project include a longitudinal SEM for PSS across diseases and syndromes and a risk score for early detection. In the second phase of funding, the final SEM and resulting risk scores will be validated and calibrated.