Abstract: : Anxiety is highly prevalent among individuals living with disability, chronic illness, or hospitalisation, yet it often remains insufficiently addressed in healthcare settings. Animal-assisted therapy (AAT) has been proposed as a complementary intervention to reduce anxiety; however, existing evidence is fragmented across populations and methodologies. : A systematic review was conducted following PRISMA 2020 guidelines. The review protocol was registered in PROSPERO (CRD42024494109); no amendments were made to the protocol after registration. Four databases (Scopus, APA PsycInfo, Web of Science, and PubMed) were searched for empirical studies (2013-2023) evaluating AAT delivered by trained professionals using domesticated species and reporting anxiety outcomes in individuals with disability, illness, or hospitalisation. : Thirty-one studies met eligibility criteria and were included in the review. Across heterogeneous designs, most interventions-primarily using dogs or horses-reported significant post-intervention reductions in anxiety. Randomised clinical trials consistently showed superior results compared with control conditions. AAT demonstrated beneficial effects across populations including PTSD, paediatric hospitalisation, chronic illness, disability, acute care, and trauma exposure. Long-term outcomes were mixed, and methodological variability limited comparability across studies. : AAT appears to be a promising complementary intervention for anxiety management within clinical, psychosocial, and healthcare settings. Evidence supports short-term anxiolytic effects across diverse populations, although standardisation and long-term evaluations remain insufficient. Future research should establish optimal intervention parameters, mechanisms of action, and strategies for integrating AAT into multidisciplinary mental healthcare.
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Overview
This research article systematically reviews the effectiveness of animal-assisted therapy (AAT) in reducing anxiety among vulnerable clinical populations such as those with disabilities, chronic illnesses, or who are hospitalized.
The review analyzes studies from the past decade to evaluate how AAT, primarily involving dogs and horses, impacts anxiety levels across various clinical settings.
Introduction and Background
Anxiety is common among individuals with disabilities, chronic illnesses, or those undergoing hospitalization, yet it is often inadequately addressed in healthcare.
Animal-assisted therapy (AAT) has been suggested as a complementary intervention to improve anxiety symptoms by leveraging interactions with trained animals.
Previous evidence on AAT’s efficacy is fragmented due to differences in study populations, methodologies, and inconsistent outcome measures.
Research Objectives and Methodology
The authors aimed to systematically review empirical studies evaluating AAT’s effectiveness in reducing anxiety in clinical populations.
They followed PRISMA 2020 guidelines for systematic reviews to ensure rigorous methodology and transparency.
The review protocol was registered with PROSPERO (CRD42024494109) to prevent bias and protocol deviations.
Four major databases were searched for relevant studies published between 2013 and 2023: Scopus, APA PsycInfo, Web of Science, and PubMed.
Inclusion criteria focused on:
Empirical studies involving AAT administered by trained professionals.
AAT interventions using domesticated animals, primarily dogs or horses.
Populations consisting of individuals with disabilities, illnesses, or hospitalizations.
Measured anxiety outcomes post-intervention.
Key Findings
A total of 31 studies met eligibility criteria and were included for review.
Most studies reported significant reductions in anxiety following AAT interventions.
Randomized clinical trials, regarded as the highest evidence level, consistently demonstrated superior anxiety reduction in AAT groups compared to controls.
AAT showed beneficial effects across diverse clinical groups including:
Post-Traumatic Stress Disorder (PTSD) patients.
Children undergoing hospitalization.
Individuals with chronic illnesses.
People living with disabilities.
Patients in acute care and those exposed to trauma.
However, long-term effects of AAT on anxiety were less consistent across studies.
Variability in study design, sample sizes, types of animals used, and anxiety measures made direct comparison across studies challenging.
Conclusions
Animal-assisted therapy is a promising complementary intervention for managing anxiety in various vulnerable clinical populations.
Evidence supports its short-term anxiolytic (anxiety-reducing) effects in clinical, psychosocial, and healthcare settings.
Current research lacks standardization of AAT protocols and sufficient long-term follow-up data.
Future research directions include:
Defining optimal intervention parameters such as session duration, frequency, and animal type.
Investigating the biological, psychological, or social mechanisms through which AAT reduces anxiety.
Developing strategies to integrate AAT into multidisciplinary mental health care frameworks effectively.
Implications for Clinical Practice
Healthcare providers may consider incorporating AAT as a complementary approach to anxiety management especially in settings where conventional interventions are limited or insufficient.
Trained animal handlers and appropriate patient selection are critical to maximize therapeutic benefits and ensure safety.
AAT offers a human-animal bond element that may enhance patient engagement and emotional wellbeing during clinical care.
Cite This Article
APA
Hernández-Espeso N, Bronchud LD, Bernabé-Valero G.
(2026).
Animal-Assisted Therapy for Reducing Anxiety in Vulnerable Clinical Populations: A Systematic Review.
Healthcare (Basel), 14(2), 260.
https://doi.org/10.3390/healthcare14020260
Faculty of Psychology, Catholic University of Valencia San Vicente Mártir, Av. De La Ilustración, 2, Burjassot, 46100 Valencia, Spain.
Bronchud, Laura Durbán
Faculty of Psychology, Catholic University of Valencia San Vicente Mártir, Av. De La Ilustración, 2, Burjassot, 46100 Valencia, Spain.
Bernabé-Valero, Gloria
Faculty of Psychology, Catholic University of Valencia San Vicente Mártir, Av. De La Ilustración, 2, Burjassot, 46100 Valencia, Spain.
Conflict of Interest Statement
No potential conflict of interest was reported by the authors.
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