This study evaluated the feasibility of recruiting hospitalized older adults into a randomized controlled trial (RCT) comparing an animal-assisted intervention (AAI) involving visits from therapy dogs with an active control (conversation with a volunteer) and treatment as usual (TU) for addressing health and mental health outcomes... This study explored the difficulties inherent in recruiting medically ill, hospitalized older adults for an RCT of hospital-based therapy dog visits.

There is some evidence that animals in therapy programs have a calming effect on people, but "the reality is we need more research," says Nancy Gee, Director of the Center for Human Animal Interaction at Virginia Commonwealth University School of Medicine. While therapy animals can include a range of species such as fish and horses, the majority of existing research is with dogs.

Oxytocin pathways are hypothesized to play important roles in human-animal interactions and may contribute to some benefits of these interspecific social relationships. We explored the effects of naturalistic interactions between children and dogs on oxytocin release in both species, as well as associations between methylation of the oxytocin receptor gene (OXTRm), social behavior, and oxytocin response in this context.

Pet ownership is associated with reduced deterioration in physical and cognitive function as older adults age... We examined the relationship of pet, dog, and cat attachment to changes in physical and cognitive function among 214 pet-owning, generally healthy, community-dwelling adults aged 50–100 years (M = 68.0, SD = 7.8) from the Baltimore Longitudinal Study of Aging (BLSA).

Loneliness is linked to significant health threats and is potentially more dangerous than obesity; it affects as many as 29% of noninstitutionalized older adults... Emerging evidence suggests that companion animals provide a number of health and well-being benefits and that interacting with a trained therapy dog may reduce loneliness.