Pathways from social disconnection to suicidal ideation in later life - ABSTRACT
Suicide deaths and social disconnection among older adults are increasingly serious public health concerns. A 'Wish
To Die' (WTD) is an indicator of passive suicide ideation which refers to thoughts of one’s own death, that one would
be better off dead, or wishing for one’s death. The association between social disconnection and suicide is widely
recognised and social disconnection has been shown to be associated with an increased likelihood of WTD.
Importantly, social disconnection is a multi-faceted construct and both the quantity (social isolation) and quality
(loneliness) of people’s social relationships are strongly related to both suicide ideation and subsequent suicide
attempts. While this association is well-established, the mechanistic pathways to explain the association are less well
understood. The main putative mechanisms proposed are: behavioral (sleep, physical activity, smoking, alcohol
consumption), psychological (depression, anxiety, and ageing perceptions), and physiological (neuroendocrine,
immune function, and cardiometabolic).
This study leverages data from The Irish Longitudinal Study on Ageing (TILDA) to identify the pathways that explain
the association between social disconnection and passive suicidal ideation. TILDA is a large, nationally
representative, prospective cohort study that examines the social, economic and health circumstances of 8,500+
community-dwelling adults aged 50 years and older in Ireland. TILDA data have been collected every two years since
2009 and includes both survey data (CAPI and SCQ) and a comprehensive clinic-based health assessment. Detailed
biomarker data are available from these health assessments and include markers from the neuroendocrine, immune,
cardiometabolic, and parasympathetic systems.
Using this longitudinal data, the study aims to: (1) Identify who is at highest risk of social disconnection and WTD
among older adults as well as when individuals are most at risk; (2) Examine the nature of the associations between
social disconnection and WTD, including strength, temporality, and directionality, among older adults; (3) Identify
mechanistic pathways that explain the association between social disconnection and WTD. To address these aims,
four waves of survey and two waves of biomarker data will be investigated and advanced longitudinal statistical
techniques (GLMM, latent growth curve, latent class growth analysis, and SEM path analysis) will be applied.
Given the complex nature of this study, we have assembled an outstanding multi-disciplinary team of clinical and
academic researchers with expertise in each of the constituent parts of the project. By establishing the causal
pathways between social disconnection and WTD, study results will identify important risk and protective factors for
suicidal ideation that are amenable to intervention. In doing so, the study will inform effective clinical and
community-based interventions by which the train of thoughts leading to active suicidal ideation can be stopped
before individuals progress to active ideation and suicidal behavior.
