Physical Exercise Transforms the Topography and Increases the Invulnerability of the Symptom Network of Depression-Anxiety in the Elderly.

BACKGROUND AND OBJECTIVES

Depression and anxiety often co-occur and have worse impacts on the elderly when experienced simultaneously. Although physical exercise may alleviate depression and anxiety, how it affects the specific symptoms is not fully understood.

METHODS

A total of 8884 participants was selected from the 2018 CLHLS database. The 10-item Center for Epidemiologic Studies Depression Scale (CESD-10) and the Generalized Anxiety Disorder Scale-7 (GAD-7) were used to assess depression and anxiety, respectively. Participants were divided into the exercise and the nonexercise groups using propensity score matching to minimize the influence of confounding variables. Depression-anxiety symptom networks were constructed, and network indexes were computed for each group, based on various packages of R. By computing network connectivity, invulnerability simulation was used to investigate the role of physical exercise in network robustness.

RESULTS

Both groups had D3 (sad mood), A4 (trouble relaxing) and A2 (uncontrollably worry) as central symptoms. In the exercise group, A1 (nervousness), A3 (too much worry) and D1 (bothered by little things) were the strongest bridge nodes. In the nonexercise group, A1 (nervousness), D1 (bothered by little things) and A4 (trouble relaxing) played this role. Participation in physical exercise decreased the centrality of D9 (cannot get doing) but increased the centrality of A3 (too much worry). Furthermore, the exercise group had higher network invulnerability than the nonexercise group under random attack conditions.

CONCLUSIONS

Physical exercise affected core symptoms of depression-anxiety and the interactions of symptoms. Targeting central or bridge nodes may be an effective intervention for alleviating the comorbidity. Increased network invulnerability manifested the positive effects of physical exercise.