Release the golden retrievers! A literature review recently published to the journal Frontiers in Psychology finds that animal-assisted therapy helps alleviate depression, post-traumatic stress disorder (PTSD) symptoms, and anxiety.

For all the coverage that therapy dogs receive in the media, scientific research exploring their actual effects is surprisingly scarce. The research team, led by Purdue University assistant professor Marguerite O’Haire, poured through the scientific literature and found just ten studies that empirically measured the effects of animal therapy on psychological symptoms. Of those studies, five focused on dogs, three focused on horses, and two used a variety of farm animals.

Studies varied widely in their design. Some focused on veterans, others on kids. Some lasted just one week, others went on for three months. Most used surveys to gauge the effects of therapy. But though the studies' designs differed, they all showed overwhelmingly positive results. Depression symptoms fell between 19 and 72 percent. Anxiety was reduced 21 to 65 percent. PTSD symptoms fell 13 to 80 percent.

While dogs were easy to work with and consistently improved patients' symptoms, therapy horses actually produced the most remarkable results.

"One study reported a 63% reduction in problem behaviors among 30 children and adolescents," O'Haire found.

She also uncovered a case study in which a veteran of the War in Iraq suffering from PTSD cultivated a relationship with a horse over twelve weeks. At the end of the study, he reported a 180 percent increase in satisfaction with quality of life, as well as vastly improved sleep that lasted well after the treatment's conclusion.

Though the published research supports animal therapy, O'Haire cautions against using it as a sole treatment.

"Given the preliminary nature of the data, we conclude that at present animal-assisted therapy shows promise as a complementary technique, but should not be enlisted as the first line of primary treatment for trauma."

She recommends that future studies recruit larger numbers of subjects, utilize control groups, strive to ascertain whether effects are short or long-term, and find ways to measure outcomes without surveys, such as tracking devices that monitor sleep and arousal. Dose reductions in drugs used to control psychological symptoms would also be a measurable outcome.

PTSD, anxiety, and depression are notoriously difficult to manage, so it's nice to see that a well-trained pooch can provide tangible relief.

Source: O'haire ME, Guérin NA and Kirkham AC (2015). Animal-Assisted Intervention for trauma: a systematic literature review. Front. Psychol. 6:1121. doi: 10.3389/fpsyg.2015.01121

(Image: AP)