Frank, Philipp;
(2023)
Inflammation, obesity, and individual symptoms of depression: Risk factor-based symptom profiles and their association with physical illness - A multicohort study.
Doctoral thesis (Ph.D), UCL (University College London).
Preview |
Text
Frank (2022)_PhD_Thesis.pdf - Accepted Version Download (60MB) | Preview |
Abstract
Background: It has been hypothesised that systemic inflammation and obesity are associated with depression, but the extent to which these associations are symptom-specific is unknown. In addition, the excess risk of physical illness in individuals with inflammation- and obesity-related symptom profiles remains poorly understood. This thesis examined the associations of systemic inflammation (study 1) and obesity (study 2) with individual depressive symptoms, as well as the associations of multiple depression measures with the incidence of physical diseases (study 3). Methods: In studies 1 and 2, individual-level data from 15 population-based cohort studies were used. Baseline assessment included two inflammatory markers (C-reactive protein and interleukin-6); body mass index; and 24 depressive symptoms ascertained using self-report questionnaires. In seven cohorts, depressive symptoms were also assessed at follow-up (mean follow-up period, 3.2 years). Study 3 used individual-level data from three large population-based cohort studies. Inflammation- and obesity-related depressive symptom profiles and eight other depression measures were ascertained from self-report or hospitalisation data. Outcome-wide follow-up included 77 common health conditions obtained from linkage to national health records. Results: Systemic inflammation and obesity were associated with distinct sets of depressive symptoms. The associations with these symptoms and their co-occurrence were stronger than those observed for overall depression and remained after multivariable adjustment, in age- and sex-stratified analyses, and in longitudinal analyses. In analyses of disease outcomes, depression was associated with increased risk for a wide range of diseases across multiple organ systems, with little differences between inflammation- and obesity-related depressive symptom profiles and other depression measures. Conclusions: The observational evidence from this thesis shows symptom-specificity in the associations of inflammatory markers and obesity with depression. Symptom-specificity was less reflected in the association between depression and the incidence of physical diseases.
| Type: | Thesis (Doctoral) |
|---|---|
| Qualification: | Ph.D |
| Title: | Inflammation, obesity, and individual symptoms of depression: Risk factor-based symptom profiles and their association with physical illness - A multicohort study |
| Open access status: | An open access version is available from UCL Discovery |
| Language: | English |
| Additional information: | Copyright © The Author 2022. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request. |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Population Health Sciences > Institute of Epidemiology and Health |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10163817 |
Archive Staff Only
 |
View Item |
