In a recent study published in JAMA Network Open, researchers evaluated the associations between psychiatric service dog partnership and post-traumatic stress disorder (PTSD) among veterans.
Study: Service Dogs for Veterans and Military Members With Posttraumatic Stress Disorder. Image Credit: parsobchai Ngammoa/Shutterstock.com
Background
PTSD is characterized by intrusion, higher arousal/reactivity, adverse cognitive and mood changes, and trauma avoidance reminders.
It is associated with various comorbidities, including generalized anxiety disorder and major depression. While current evidence-based PTSD treatments are effective for some people, retention and uptake are limited.
Preliminary reports suggest that psychiatric service dog partnerships have been shown to improve self-reported PTSD symptoms in veterans.
Nevertheless, only one clinical trial has compared service dogs and emotional support dogs, preventing conclusions regarding service dogs relative to usual care. Besides, studies on service dogs have not relied on blinded clinician ratings to assess PTSD severity outcomes.
About the study
In the present study, researchers examined the associations between psychiatric service dog partnerships and PTSD symptom severity, psychological functioning, anxiety, and depression among veterans.
They compared veterans receiving a trained service dog and usual care (intervention group) to those on a waiting list for a service dog, who received usual care (controls).
Veterans aged ≥ 18 were recruited between August 2017 and December 2018, who were in military service on/after September 11, 2001, applied for a service dog, and had PTSD, current honorable service or discharge, and no convictions for crimes against animals.
Breeds mainly were mixed (59%); service dogs underwent professional training for ≤ 60 hours and passed final tests on specialized skills and obedience.
Veterans and service dogs were paired for an onsite group class for three weeks. The curriculum involved instructions in service dog training, care, interaction, and assessments.
The veteran-service dog pairs passed a standardized test showing safety and control in public. Both intervention and control subjects had access to usual care without restrictions.
Outcomes were evaluated at baseline and follow-up (three months later). The primary outcomes included PTSD symptom severity, anxiety, and depression.
The clinician-administered PTSD scale for DSM-5 (CAPS-5) and the self-reported PTSD checklist for DSM-5 (PCL-5) were used to measure PTSD symptom severity. Clinicians were masked to condition allocation, study design, topic, and timing.
PTSD was diagnosed based on CAPS-5. Anxiety and depression were measured using the patient-reported outcomes measurement system (PROMIS) anxiety and depression scores, respectively. Secondary outcomes included psychosocial functioning, such as social health and quality of life. The Columbia suicide severity rating scale measured suicidality.
Findings
Overall, 200 veterans were screened for eligibility, and 170 were eligible for inclusion. Eighty-one veterans received a service dog, while 75 were on the waiting list. Of these, 143 and 135 individuals completed the follow-up PCL-5 and CAPS-5 assessments, respectively.
The mean age of veterans was 37.6. Most participants were male (75%) and White (76%). Intervention subjects reported significantly lower severity of PTSD symptoms at three months than controls based on PCL-5.
Further, a significant difference was observed in the odds of meeting CAPS-5 criteria for PTSD diagnosis, with 75% of intervention subjects receiving a PTSD diagnosis at follow-up compared to 85% of controls.
PROMIS depression scores were significantly lower among intervention subjects at follow-up than among controls. The intervention group had a lower probability of mild depression.
PROMIS anxiety scores were also significantly lower in the intervention group. The probability of generalized anxiety disorder was lower among intervention subjects. Further, the intervention group showed better social health, with higher companionship and less social isolation, than the control group. However, there were no differences in social activity.
Compared to controls, the intervention group exhibited improved quality of life, showing less anger, greater life satisfaction and resilience, and better mental health and well-being. Suicidality was observed at baseline through follow-up.
PCL-5 and CAPS-5 subscale analyses indicated that partnership with a service dog was associated with lower PTSD symptom severity across all domains. In total, participants reported 11 adverse events.
Conclusions
Taken together, veterans with a service dog partnership had significantly lower clinician-rated and self-reported PTSD symptom severity, depression, and anxiety, higher quality of life, and mixed social health outcomes than controls.
The study’s limitations include non-random treatment allocation and non-generalizability to those not seeking out service dogs. Besides, a single organization trained service dogs; as such, adherence, fidelity, and dropout rates may vary across organizations.
