The Association Between Companion Animal Attachment and Depression: A Systematic Review

Abstract

ABSTRACT There is significant literature related to companion animal attachment and depression, but to date, there has not been a systematic review of it. The aims of this systematic review were threefold: (1) to compare depression outcomes between pet and non-pet owners; (2) to identify the prevalence of how attachment is operationalized within the human–pet relationships literature, as it is defined in two distinct, divergent ways: as an attachment bond or as an attachment orientation; and (3) to review and synthesize the existing literature related to the association between pet attachment and depression. A search of five databases (Pubmed, Medline, Web of Science, Embase, and PsycInfo) was conducted in January 2024 to locate articles (journal articles, dissertations) focusing on pets, attachment, and depression or depressive symptoms that met predefined inclusion and exclusion criteria. In total, 40 studies were included in the review. Eighteen studies compared depression outcomes in pet owners and non-pet owners; of these, 14 found no significant difference in depression between the two groups, while four found that pet owners were significantly less depressed than non-pet owners. Most studies measuring attachment bond revealed a positive or non-significant relationship with depression, while the majority of studies measuring attachment orientation indicate that higher levels of secure attachment are negatively associated with depression, while higher levels of attachment insecurity are typically positively associated with depression. We conclude that the field needs more clarification regarding the definition of attachment so that meaningful conclusions regarding the impact of pet attachment on mental health can be drawn.