Depressive Symptom Network Associated With Comorbid Anxiety in Late-Life Depression

Min Ho An; Soon Sang Park; Seng Chan You; Rae Woong Park; Bumhee Park; Hyung Kyoo Woo; Han Ki Kim; Sang Joon Son

doi:10.3389/fpsyt.2019.00856

Depressive Symptom Network Associated With Comorbid Anxiety in Late-Life Depression

Front Psychiatry. 2019 Nov 20:10:856. doi: 10.3389/fpsyt.2019.00856. eCollection 2019.

Authors

Min Ho An¹, Soon Sang Park¹, Seng Chan You², Rae Woong Park², Bumhee Park², Hyung Kyoo Woo¹, Han Ki Kim¹, Sang Joon Son³

Affiliations

¹ Ajou University School of Medicine, Suwon, South Korea.
² Department of Biomedical Informatics, Ajou University School of Medicine, Suwon, South Korea.
³ Department of Psychiatry, Ajou University School of Medicine, Suwon, South Korea.

Abstract

Background: Depression and anxiety are the most common comorbid psychiatric disorders in the elderly. Psychiatrists have been reporting worsened depression symptoms and prognosis by comorbid anxiety symptoms. However, it is still unclear how anxiety affects the course of depression in the elderly. The aims of this study are (1) to identify the symptom network in late-life depression (LLD), and (2) to examine the role of anxiety in LLD with a network perspective. Methods: The study analyzed 776 community-based participants who were clinically diagnosed with depression and enrolled in Suwon Geriatric Mental Health Center. Network analysis was used to investigate the relationships between the symptoms of the Montgomery-Åsberg Depression Rating Scale (MADRS). The depression sample was divided into groups of low and high anxiety according to the Beck Anxiety Index. Propensity score matching (PSM) was used to minimize the effects of depression severity on the network. Network comparison test (NCT) were carried out to compare the global connectivity, global strength, and specific edge strength between the two subgroups. Results: Reported sadness, pessimistic thinking, and suicidal ideation are the core symptoms of LLD in terms of node strength. The MADRS sum score [mean (SD) 28.10 (9.19) vs 20.08 (7.11); P < .01] was much higher in the high anxiety group. The NCT before PSM showed the high anxiety group had significantly higher global strength (P < .01). However, the NCT after PSM did not reveal any statistical significance both in global structure (P = .46) and global strength (P = .26). A comparison between centrality indices showed a higher node strength of vegetative symptoms in the high anxiety group and this also remained after PSM. Conclusion: Based on the statistical analysis, anxiety worsens the severity of depression in the elderly. However, NCT after PSM revealed comorbid anxiety does not change the global structure and strength of the depression symptom network. Therefore, anxiety may affect LLD in a way of worsening the severity, rather than changing psychopathology. Additionally, the study revealed the centrality of vegetative symptoms was low in LLD but increased substantially in patients with comorbid anxiety.

Keywords: anxiety; depression; geriatric (aging); network analysis; psychopathology.