Loneliness in the Millennium A Behavioural Epidemiology Approach to the Profile of Loneliness and Interventions Across the Lifespan

Abstract

Loneliness is a growing health concern and has recently been considered an ‘epidemic’ by prominent health leaders. For this reason, loneliness has started to emerge as a problem, not only in psychology but also in other areas, including public health. In this thesis I aim to investigate loneliness through a public health lens, evaluating current literature regarding the prevalence and trends, measures and interventions, and providing recommendations for future research. I present findings from a systematic review and meta-analysis synthesising the prevalence of loneliness in 113 countries. Loneliness was found to be most prevalent in adolescents/young adults and older adults. I used the Health and Retirement Study to identify trends and predictors of loneliness in older American adults. Overall, both episodic and sustained loneliness prevalence have decreased over the last 25 years. Women, non-Caucasians, those with lower education levels, unemployed/retired, and not married/partnered were found to be at higher risk for problematic loneliness. I discuss the relationship between loneliness and physical activity, with low participation in physical activity being found to be a predictor of future loneliness. I reviewed the literature to evaluate other interventions for loneliness among adolescents/young adults. Social access interventions were found to be the most effective type of loneliness intervention, but it is unclear if this is due to a lack of research regarding other intervention types.

More rigorous systematic surveillance is required to monitor loneliness and population-level interventions are required to tackle loneliness as a public health issue. Current research and surveillance are hampered by a lack of comparable data, particularly in countries outside of Europe and for underserved groups across the lifespan (i.e., young child and middle-aged adult populations).