Military Veterans and Their PTSD Service Dogs: Associations Between Training Methods, PTSD Severity, Dog Behavior, and the Human-Animal Bond

The Welfare of Dogs as an Aspect of the Human-Dog Bond: A Scoping Review

The close bond that can exist between humans and their dogs is an important aspect of the evolutionary, economic, and social connections between the two species. There is a need for a better understanding of the place of the dog within the human-dog bond and on ways the human-dog bond affects dog welfare. We conducted a scoping review to investigate to what extent and in what ways dog welfare is addressed in the research literature on the human-dog bond. We identified 706 publications on the human-dog bond from across the globe that were published from 2012 to 2023. We found that 246 of these 706 publications had a focus on dog welfare. Our review showed that the interplay of characteristics and backgrounds of owners/handlers and their dogs was linked to dog welfare in multiple, both positive and negative, ways. Our review is limited by the fact that most of the research that we reviewed involved pet dogs and in majority came from Western, Educated, Industrialized, Rich, Democratic (WEIRD) societies. There is a need for a better understanding of how the human-dog bond affects the welfare of working, assistance, and service dogs.

Insights into Canadians' Perceptions of Service Dogs in Public Spaces

Service Dogs (SDs) are an increasingly common type of working dog supporting people with disabilities in Canada. One of the groups being paired with SDs is Veterans diagnosed with posttraumatic stress injuries (PTSIs). In past research, Veterans have expressed stress over negative interactions with people in public spaces because an SD brings attention to their disability. There is a dearth of research exploring perceptions of SDs in public settings.

METHODS

A total of 485 Canadians were surveyed via an online questionnaire about their demographic information and beliefs about SDs in public spaces. Data were analyzed using robust ordinary least squares (OLS) regression to determine which demographic features, if any, contribute to perceptions.

RESULTS

Generally, the Canadian public holds highly positive perceptions of SDs being in public spaces. Our analysis found that women, people who currently have pets, and Indigenous people were more supportive of SDs in public spaces than others. People with certain cultural heritages were less receptive.

CONCLUSION

These findings are an important beginning contribution to the growing SD and Veteran health field.

Hair Cortisol in Service Dogs for Veterans with Post-traumatic Stress Disorder Compared to Companion Dogs (Canis Familiaris)

Service dogs are trained to assist humans. This assistance potentially exposes them to stressors To investigate if service dogs are exposed to more stressors than companion dogs we questioned whether hair cortisol levels differed between both groups. We studied this by cutting a tuft of hair from the neck of 19 companion and 11 service dogs. Cortisol levels were subsequently analyzed via immunoassay and compared via a simple linear regression model. The influence of coat color, season, sex, other dogs, pets, or mental health diagnoses in the household was also checked . Results showed that cortisol values did not differ between service and companion dogs. Furthermore, none of the additional variables had an influence on cortisol levels. This lead to the conclusion that the service dogs in this study did not have higher hair cortisol levels than companion dogs Further study should be conducted as to why no difference did occur between groups and if this difference is persistent over time given that we only studied a period of up to two months' worth of hair cortisol.

A Qualitative Exploration of the Use of Service Dogs in Veterans with Post Traumatic Stress Disorder and Traumatic Brain Injury

Objective

This qualitative research was conducted to add to the body of knowledge that supports the benefits of service dogs (SDs), as a tertiary treatment modality, to veterans with post-traumatic stress disorder (PTSD) and/or traumatic brain injury (TBI).

Methods

This grounded theory research design utilized open-ended, semi-structured interviews with veterans (n = 10) who were using SDs as a treatment modality for PTSD and/or TBI. Transcripts were analyzed using NVivo qualitative software until data saturation was achieved.

Results

Results from the data analysis identified 4 major themes with concurrent subthemes. The most prominent themes were functional status, impact of a SD, recognition of symptoms of PTSD and/or TBI by the SD, and barriers and challenges to the acquisition of a SD. Participants reported that the SD increased socialization and was a positive adjunct to treatment modalities for PTSD and/or TBI.

Conclusions

Our study highlights the benefits of using a SD as a tertiary treatment for PTSD and/or TBI in veterans. Veterans in our study articulated the benefits of using a SD as a tertiary treatment option, and the need to make this a standard treatment option for all veterans who suffer from PTSD and/or TBI.

Assistance dogs for military veterans with PTSD: A systematic review, meta-analysis, and meta-synthesis

Psychiatric assistance dogs for military veterans with posttraumatic stress disorder (PTSD) currently make up over 19% of assistance dog partnerships globally. We conducted a systematic review of the literature relating to these partnerships, with specific aims to (1) summarize their characteristics, (2) evaluate the quality of existing evidence, and (3) summarize outcomes. A total of 432 records were independently screened (Cohen’s kappa = 0.90). Of these, 41 articles (29 peer-reviewed publications and 12 unpublished dissertations) met inclusion criteria. Data extraction was conducted to address the research aims, including a meta-analysis (quantitative outcomes) and meta-synthesis (qualitative outcomes). All peer-reviewed publications on the topic of psychiatric assistance dogs for veterans with PTSD were published within the last five years. The majority of included articles were quantitative (53%), 41% were qualitative, and 6% employed mixed methods. Mean methodological rigor scores were 80% for peer reviewed articles and 71% for dissertations, where higher scores represent more rigorous methodology. Quantitative articles reported significant improvements in the domains of PTSD severity, mental health, and social health. Impacts on physical health and global quality of life appear inconclusive. Meta-analysis (9 articles) revealed that partnership with an assistance dog had a clinically meaningful, significant, and large effect on PTSD severity scores (g = −1.129; p<0.0001). Qualitative meta-synthesis identified two third order constructs: (1) Impact on the individual: mental & physical health and (2) Impact beyond the individual: building relationships & connection. This synthesis of increasingly prevalent research on assistance dogs for veterans with PTSD provides support for the impact of this complementary and integrative health intervention on PTSD symptom severity, and signs of meaningful improvements in adjacent domains including mental and social health. Gaps between quantitative and qualitative findings, along with the need to report greater demographic detail, highlight key opportunities for future research.

Characterizing veteran and PTSD service dog teams: Exploring potential mechanisms of symptom change and canine predictors of efficacy

Psychiatric service dogs are an emerging complementary intervention for posttraumatic stress disorder (PTSD). Initial evidence suggests that partnership with a service dog may be related to less PTSD symptom severity. However, it remains unclear how or why this might occur. To address this gap, we conducted a longitudinal investigation of 82 post-9/11 military members or veterans and their PTSD service dogs to (1) evaluate service dog characteristics as potential predictors of efficacy, (2) assess dog and human characteristics as potential predictors of veteran-dog bond, and (3) explore potential mechanisms for mental health outcomes. Aim 1 results demonstrated that most service dog characteristics did not predict veterans’ mental health outcomes, but lower service dog excitability was associated with less PTSD symptom severity at follow-up. Aim 2 results showed that closer dog-veteran relationships were associated with less excitable dog temperament. Aim 3 results indicated that worse mental health at follow-up was associated with greater use of the specifically trained PTSD service dog task to initiate a social greeting (“make a friend”), whereas better mental health was related to less use of dominance-based training methods, lower perceived emotional/logistical costs of service dog partnership, and closer veteran-dog relationships. More frequent use of the trained service dog task to signal when someone approaches from behind (cover/watch back) was associated with greater anxiety, but less PTSD symptom severity. Overall, veterans spent an average of 82% of their time with service dogs (assessed via Bluetooth proximity between dog collar and veteran smartphone), and most frequently asked their service dogs to perform the trained task for calming their anxiety (calm/comfort anxiety). The present study provides subjective and objective metrics of the heterogeneity among veteran-service dog dyads while also suggesting which of the assessed metrics might be potential mechanisms involved in the intervention.

Impacts of COVID-19 on Owner's Veterinary Healthcare Seeking Behavior for Dogs With Chronic Conditions: An Exploratory Mixed-Methods Study With a Convenience Sample

This mixed-method study explored the impacts of the COVID-19 pandemic on owners' veterinary healthcare seeking, with particular focus on dogs with chronic conditions. A convenience sample of 719 UK dog owners completed an online survey (December 2020-January 2021). Differences in treatment provision and respondents' decisions to seek care across acute, preventative, chronic conditions and for end-of-life care were explored. Multivariable logistic regression models were used to identify factors associated with seeking care for any health issue compared to deciding against it, and urgency to seek care given symptom that could indicate chronic conditions. Open-ended questions were analyzed by thematic analysis. Significant (p-value < 0.05) differences in care seeking decisions were identified regarding access to veterinary care and the way treatment was provided across all health issues. The top reasons for not seeking care across all health issues were a lack of access to a veterinarian (30%, n = 56/187) and a reluctance for a dog to go to the clinic unaccompanied (20%, n = 38/187). Variables related to stronger dog-owner relationship, higher confidence in seeking care, perception of: benefits of veterinary care, dog's high susceptibility to illness and high severity of dog's condition, increased the odds of seeking, and urgency to seek, care. A dog's chronic illness diagnosis reduced the odds of seeking care during the pandemic, reportedly due to difficulties in accessing care for non-urgent issues. Qualitative analysis showed that limited access to routine consultations, delays in test results and restricted access to complementary treatments, led some owners of dogs with chronic conditions to believe that their dog's welfare had deteriorated during the pandemic. Pandemic control measures necessitated changes to how consultations were run. These changes were often viewed favorably, but dog-client separation during consultations were considered problematic, sometimes delaying veterinary advice-seeking, including for euthanasia. Separating owners from their dogs during veterinary consultations should be avoided wherever possible due to impacts on dogs, owners and healthcare seeking. Interventions to improve veterinary healthcare seeking could target attitudes toward benefits of seeking care, improve owners' self-efficacy and capitalize on the dog-owner bond. Such interventions should be implemented alongside interventions aimed at removing structural barriers to accessing healthcare.

Congenital idiopathic megaesophagus in the German shepherd dog is a sex-differentiated trait and is associated with an intronic variable number tandem repeat in Melanin-Concentrating Hormone Receptor 2

Congenital idiopathic megaesophagus (CIM) is a gastrointestinal (GI) motility disorder of dogs in which reduced peristaltic activity and dilation of the esophagus prevent the normal transport of food into the stomach. Affected puppies regurgitate meals and water, fail to thrive, and experience complications such as aspiration pneumonia that may necessitate euthanasia. The German shepherd dog (GSD) has the highest disease incidence, indicative of a genetic predisposition. Here, we discover that male GSDs are twice as likely to be affected as females and show that the sex bias is independent of body size. We propose that female endogenous factors (e.g., estrogen) are protective via their role in promoting relaxation of the sphincter between the esophagus and stomach, facilitating food passage. A genome-wide association study for CIM revealed an association on canine chromosome 12 (P-val = 3.12x10^-13), with the lead SNPs located upstream or within Melanin-Concentrating Hormone Receptor 2 (MCHR2), a compelling positional candidate gene having a role in appetite, weight, and GI motility. Within the first intron of MCHR2, we identified a 33 bp variable number tandem repeat (VNTR) containing a consensus binding sequence for the T-box family of transcription factors. Across dogs and wolves, the major allele includes two copies of the repeat, whereas the predominant alleles in GSDs have one or three copies. The single-copy allele is strongly associated with CIM (P-val = 1.32x10^-17), with homozygosity for this allele posing the most significant risk. Our findings suggest that the number of T-box protein binding motifs may correlate with MCHR2 expression and that an imbalance of melanin-concentrating hormone plays a role in CIM. We describe herein the first genetic factors identified in CIM: sex and a major locus on chromosome 12, which together predict disease state in the GSD with greater than 75% accuracy.

German shepherd dogs (GSDs) are predisposed to an inherited motility disorder of the esophagus, termed congenital idiopathic megaesophagus (CIM), in which swallowing is ineffective and the esophagus is enlarged. Affected puppies are unable to properly pass food into their stomachs and consequently regurgitate their meals and show a failure to thrive, often leading to euthanasia. Here, we discovered that male GSDs are affected at a ratio of almost 2-to-1 over females, suggesting a protective biological advantage in females. In humans, estrogen is thought to play a role in the male predominance of esophageal disorders like reflux esophagitis and esophageal cancer. In a genome-wide scan, we identified an association with CIM on chromosome 12 and, within this region, a repetitive sequence in MCHR2. This gene encodes a receptor for melanin-concentrating hormone, a signaling molecule that is linked to appetite, weight, and gut motility. Together, sex and the MCHR2 repeat sequence accurately predict affection status in over 75% of dogs, and a genetic test is now available to facilitate breeding decisions aimed at reducing disease incidence.

Expectations versus experiences of veterans with posttraumatic stress disorder (PTSD) service dogs: An inductive conventional content analysis

[Correction Notice: An Erratum for this article was reported in Vol 14(3) of Psychological Trauma: Theory, Research, Practice, and Policy (see record 2022-33825-001). In this article, the length of time in which service dogs had been paired with Veterans was reported incorrectly in the third paragraph under the "Participants" heading of the "Methods" section whereby the sentence "Participants with a service dog had received their PTSD service dog an average of 51.5 months prior to participating in the study (range = 3-121.7 months, SD = 33.3)." should have read "Participants with a service dog had received their PTSD service dog an average of 20.9 months prior to participating in the study (range = 1.2-46.23 months, SD = 13.18)." All versions of this article have been corrected.] Objective: The objective of this study was twofold: to describe the benefits and drawbacks of a posttraumatic stress disorder (PTSD) service dog from the perspective of Veterans with service dogs and to compare these reports to the expectations of Veterans who were on a waitlist for a PTSD service dog. Method: A total of 128 U.S. post-9/11 Veterans with PTSD were recruited from a nonprofit service dog provider (K9s for Warriors), including n = 69 with a PTSD service dog and n = 59 on the waitlist. Participant responses to open-ended survey questions were analyzed with conventional content analysis and classified into 214 codes across six subthemes, creating three larger themes. A subset (20%) of the data was independently coded to establish interrater reliability (Cohen's κ = .804). Frequency data were used to compare theme and subtheme prevalence between groups. Results: Veterans' experiences and expectations were centered on the effects the service dogs had on Veteran mental health, human-dog interaction, and the associated drawbacks. Although the majority of Veterans reported benefits from their service dogs, the findings revealed that Veterans on the waitlist more frequently mentioned benefits than those with a service dog. Study findings suggest that the drawbacks expected from service dogs differ from the drawbacks experienced. Conclusion: Understanding expectations versus experiences provides critical information for mental health professionals who are informing Veterans on individualized interventions for PTSD. This knowledge will enable professionals to temper expectations and educate Veterans on specific benefits and drawbacks so that they have a more rounded view of PTSD service dogs. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Dog Walking before and during the COVID-19 Pandemic Lockdown: Experiences of UK Dog Owners

Background: This study investigated the impacts of the first COVID-19 UK lockdown on dog walking and ownership. Methods: An online survey was circulated via social media (May–June 2020). Completed responses (n = 584) were analysed using within- and between-group comparisons, and multivariable linear and logistic regression models were created. Open-ended data were coded into key themes. Results: During lockdown, dogs were walked less frequently, yet for a similar duration per week and closer to home. Dogs whose owners lived alone, or whose owners or household members had heightened vulnerability to COVID-19 were walked less than before, as were high-energy dogs. A minority of owners continued dog walking despite exhibiting symptoms or needing to self-isolate, justifying lack of help, dog behavioural problems, living in less populated areas, and the importance of outdoor exercise for their mental health. Dog ownership had multiple benefits (companionship, purpose and motivation; break from bad; positive to focus on) as well as challenges (changes in dog behaviour, balancing dog needs with public health guidance, accessing pet food/supplies and services, and sharing crowded outdoor spaces with others). Most did not have an emergency care plan for their pet before the pandemic and only a handful developed one. Conclusions: Findings can be used to inform public health and dog welfare strategies for future lockdown situations or other disasters and emergencies likely to impact on daily routines.

Variability in Human-Animal Interaction Research

The field of Human-Animal Interaction (HAI) is plagued with mixed results. Some findings appear to indicate that interacting with a companion animal is beneficial for some aspect of human health and well-being, while other research outcomes are inconclusive or even indicate the opposite. The purpose of this paper is to take a closer look at this variability in research outcomes and to provide plausible explanations and potential remedies. Some of the reasons for mixed results are likely due to the wide variety of methodologies implemented, intermittent use of standardized measures and manualized protocols, variability in human and animal participants, and limited quantification of human-animal interactions or definitions of pet ownership. Variability in research outcomes is not unique to HAI and is, in fact, not uncommon in many more established fields such as psychology and medicine. However, the potential reasons for the variability may be linked to the unique nature of HAI in that, in its' simplest form, it involves two complex organisms, a human and an animal, interacting in dynamic ways. We argue that this complexity makes research in this field particularly challenging and requires a broad spectrum of theoretical and methodological considerations to improve rigor while ensuring the validity and reliability of conclusions drawn from study results.

The effects of assistance dogs on psychosocial health and wellbeing: A systematic literature review

Beyond the functional tasks that assistance dogs are trained for, there is growing literature describing their benefits on the psychosocial health and wellbeing of their handlers. However, this research is not only widely disparate but, despite its growth, has not been reviewed since 2012. Our objective was to identify, summarize, and methodologically evaluate studies quantifying the psychosocial effects of assistance dogs for individuals with physical disabilities. Following PRISMA guidelines, a systematic review was conducted across seven electronic databases. Records were independently screened by two authors. Studies were eligible for inclusion if they assessed outcomes from guide, hearing, medical, or mobility service dogs, if they collected original data on handlers' psychosocial functioning, and if the outcome was measured quantitatively with a validated, standardized measure. Studies on psychiatric service dogs, emotional support dogs, and pet dogs were excluded. Of 1,830 records screened, 24 articles were identified (12 publications, 12 theses) containing 27 studies (15 cross-sectional, 12 longitudinal). Studies assessed the effects of mobility (18), hearing (7), guide (4), and medical (2) assistance dog partnerships with an average sample size of N = 83. An analysis of 147 statistical comparisons across the domains of psychological health, quality of life, social health, and vitality found that 68% of comparisons were null, 30% were positive in the hypothesized direction, and 2% were negative. Positive outcomes included significant effects of having an assistance dog on psychological wellbeing, emotional functioning, self-esteem, and vitality. However, it is of note that several methodological weaknesses of the studies make it difficult to draw any definitive conclusions, including inadequate reporting and a failure to account for moderating or confounding variables. Future research will benefit from stronger methodological rigor and reporting to account for heterogeneity in both humans and assistance dogs as well as continued high-quality replication.

Dog cognitive development: a longitudinal study across the first 2 years of life

While our understanding of adult dog cognition has grown considerably over the past 20 years, relatively little is known about the ontogeny of dog cognition. To assess the development and longitudinal stability of cognitive traits in dogs, we administered a battery of tasks to 160 candidate assistance dogs at 2 timepoints. The tasks were designed to measure diverse aspects of cognition, ranging from executive function (e.g., inhibitory control, reversal learning, memory) to sensory discrimination (e.g., vision, audition, olfaction) to social interaction with humans. Subjects first participated as 8-10-week-old puppies, and then were retested on the same tasks at ~ 21 months of age. With few exceptions, task performance improved with age, with the largest effects observed for measures of executive function and social gaze. Results also indicated that individual differences were both early emerging and enduring; for example, social attention to humans, use of human communicative signals, independent persistence at a problem, odor discrimination, and inhibitory control all exhibited moderate levels of rank-order stability between the two timepoints. Using multiple regression, we found that young adult performance on many cognitive tasks could be predicted from a set of cognitive measures collected in early development. Our findings contribute to knowledge about changes in dog cognition across early development as well as the origins and developmental stability of individual differences.

Defining the PTSD Service Dog Intervention: Perceived Importance, Usage, and Symptom Specificity of Psychiatric Service Dogs for Military Veterans

Research suggests that psychiatric service dogs may be an effective complementary treatment option for military veterans with posttraumatic stress disorder (PTSD). Although this practice continues to increase in popularity and research has reached the rigor of clinical trials, the components of the PTSD service dog intervention remain largely undefined. This research aimed to (1) quantify the importance, usage, and PTSD symptom specificity of service dog trained and untrained behaviors, (2) explore how PTSD severity, time since receiving the service dog, and the veteran-dog relationship relate to outcomes, and (3) compare expectations of veterans on the waitlist to experiences of veterans with service dogs. In a cross-sectional design, 217 post-9/11 military veterans with PTSD were recruited from a national service dog provider, including n = 134 with a service dog and n = 83 on the waitlist. Results showed that the service dog's trained tasks of calming and interrupting anxiety were perceived as the most important for veterans' PTSD, the most frequently used in a typical day, and as helping the most PTSD symptoms. Trained tasks were most helpful to the PTSD symptoms of hypervigilance and intrusion, and least helpful toward the symptoms of amnesia and risk-taking. Although all trained tasks were helpful toward PTSD symptoms, veterans rated the service dog's untrained behaviors on average as more important for their PTSD. After controlling for covariates, there was no relationship between a veteran's PTSD severity and perceived importance or frequency of task use. However, veterans who reported feeling closer to their service dogs reported using trained tasks more often, and veterans who had their service dogs for longer reported using trained tasks less often. Finally, veterans on the waitlist reported higher expectations regarding task use and importance than described by veterans with a service dog. In conclusion, findings describe the core components of the PTSD service dog intervention by quantifying the use and value of trained and untrained dog behaviors. Overall, this study helps explain the PTSD service dog's clinically relevant value while contributing to the scientific understanding of this emerging practice.

Toxocara: Protecting pets and improving the lives of people

Toxocara sp. are zoonotic parasitic roundworms that cause infection and morbidity in both developed and developing countries. In humans, infection is thought to be most common in children, particularly those living in poverty, and usually results from consumption of soil contaminated with parasite eggs deposited by dog or cat faeces. Infection in humans results in different clinical manifestations, some more overt like visceral or ocular larva migrans and others more cryptic like neurocognitive delay. Despite its pervasiveness, toxocariasis has become a neglected infection. We review the dynamics of the human-animal interface in the context of this parasite, discuss the challenges in controlling transmission to humans, and cite key areas of research that could enable improved interventions. With political will and proper resource allocation, we propose that effective interventions are possible in the near term.

Enhancing Success of Veterinary Visits for Clients With Disabilities and an Assistance Dog or Companion Animal: A Review

Despite increasing information on enhancing client communication and compliance/adherence in veterinary medicine, literature focusing on special cases remains limited: working with clients with special needs, challenges or disabilities, or when the patient is an assistance or emotional support animal. This paper summarizes current recommendations on how best to build successful working relationships with these clients, including action items to implement in practice. In addition, this paper reviews current literature on important considerations for care of assistance dogs as patients.