p-ISSN: 1454-7848
e-ISSN: 2068-7176



Un număr mare de cercetări recente subliniază beneficiile interacţiunii om-animal asupra sănătăţii. Terapia asistată de animale care include animale de casă (pisici, câini), cai şi delfini a fost implementată în diverse centre medicale şi non-medicale (inchisori, adăposturi pentru veterani, etc). Beneficiile demonstrate includ aspecte fiziologice şi psihologice. Beneficiile de natură fiziologică implică ameliorări ale valorilor tensiunii arteriale şi alurii ventriculare. Depresia, anxietatea şi funcţiile cognitive sunt cele mai importante simptome care pot beneficia de aportul terapiei asistate de animale.


Animal assisted therapy (AAT) involves an interaction between patients and a certified trained animal, which purpose is to facilitate the patients’ progress toward a therapeutic goal.
Delta Society, one of the most important organizations involved in the certification of therapy animals in USA defined animal assisted therapy as a goal directed intervention in which an animal that meets specific criteria is an integral part of the treatment process. AAT is directed and/or delivered by a health/service professional with specialized expertise and within the scope of his/her profession. Key features include: specific goals and objectives for each individual and measure progress. Animal assisted activities (AAA) are defined by the same organization, as activities that provide opportunities for motivational, educational, recreational and/or therapeutic benefits to enhance quality of life. AAA are delivered in a variety of environments by specially trained professionals and/or volunteers, in association with animals that meet specific criteria (1).
The goal of AAT is to improve a patient’s social, emotional, or cognitive functioning. A therapist who brings along a pet may be viewed as being less threatening, increasing the rapport between patient and therapist (2). Wilson’s, 1984 (3) biophilia hypothesis is based on the premise that our attachment and interest in animals stems from the strong possibility that human survival was partly dependent on signals from animals in the environment indicating safety or threat. The biophilia hypothesis suggests that now, if we see animals at rest or in a peaceful state, this may signal to us safety, security and feelings of well-being which in turn may trigger a state where personal change and healing are possible. (3). The earliest reported use of AAT for the mentally ill took place in the late 18th century at the York Retreat in England, led by William Tuke (4). Patients at this facility were allowed to wander the grounds which contained a population of small domestic animals. These were believed to be effective tools for socialization. In 1860, the Bethlem Hospital in England followed the same trend and added animals to the ward, greatly influencing the morale of the patients living there (5).
Animals can be used in a variety of settings such as prisons, nursing homes, mental institutions and hospitals. Assistance dogs can also assist people with many different disabilities; they are capable of assisting certain life activities and help the individuals navigate outside of the home (6). In the last decades AAT has received a growing interest and it has been used in several medical areas. There are studied involving canine assisted therapy conducted in cardiology departments, pediatric clinics, pain management clinics, emergency rooms, psychiatry clinics, etc. The documented benefits of AAT include improved physical, emotional, cognitive, and social functioning; reduced blood pressure and triglyceride levels; and even reduced cardiovascular morbidity and mortality (7).
Psychiatric patients benefit by reduced stress. Patients with heart failure have lower epinephrine and norepinephrine levels, with systolic pulmonary artery and pulmonary capillary wedge pressure reductions after AAT (5).

Animal assisted therapy has already proven its efficacy as reported by clinical studies. Thus, several studies conducted in cardiology departments showed a decrease in blood pressure and heart rate for the participants after the interaction with trained animals and an increase in peripheral skin temperature (8, 9, 10). In one study, (11) patients who were pet owners with long-term animal exposure had lower blood pressure, heart rate, and plasma rennin activity in response to mental stressors (mathematical subtraction, speech) than did patients who were not pet owners. In patients who survived myocardial infarction, the risk for cardiovascular disease, morbidity, and mortality 1 year after the infarction was lower in those who were pet owners than in those who were not (12, 13). In the Cardiac Arrhythmia Suppression Trial, dog ownership was a significant independent predictor of survival in patients 1 year after acute myocardial infarction. These data support the hypothesis that excess activity of the sympathetic nervous system due to both physiological and psychological stress can be reduced by AAT.
Patients with advanced heart failure are threatened by many physiological and psychological stressors (14, 15). Physiological stressors include the activation of the neuroendocrine cascade, most likely triggered by excitation of the sympathetic nervous system (16). In a patient with heart failure, the presence of a non- threatening stimulus such as a dog could relax the patient by lowering the patient’s state of arousal and reduce neurohormonal activation caused by over activity of the sympathetic nervous system (17, 18).
A recent study conduced by Cole et al (19) assessed 76 patients with a diagnosis of advanced heart failure. The aim of the study was to determine whether the interaction between patients and therapy dogs improves hemodynamic measures, lowers neurohormone levels, and decreases state anxiety. The patients were divided into three groups: the first group received the visit of a volunteer, in the second group the patients were asked to relax quietly in the bed, whereas the third group received a visit form a trained therapy dog. For all groups relaxation interventions lasted 12 minutes. The physiological variables (blood pressure, heart rate, cardiac index, SVR, epinephrine level, and norepinephrine level) were assessed 3 times for all groups. Results showed that animal-assisted therapy improves cardiopulmonary pressures, neurohormone levels, and anxiety in patients hospitalized with heart failure. The review of Wolff et al (20) highlighted the positive effects of human-animal interaction on the cardiovascular system and on the improved survival after a myocardial infarct for pet owners. It also emphases the importance for further research in order to the complex elucidate physiological mechanism underlying these benefits.
Dog assisted therapy’s potential benefits were also assessed in several pain management clinics. A study conducted by Marcus et al (21) included two hundred ninety-five therapy dog visits (235 with patients, 34 family/friends, and 26 clinic staff). Participants were able to spend the waiting time in the clinic with a certified therapy dog instead of waiting in the outpatient waiting area. Self-reported pain, fatigue, and emotional distress were recorded using 11-point numeric rating scales before and after the therapy dog visit or waiting room time. Results showed that therapy dog visits in an outpatient setting provided significant reduction in pain and emotional distress for chronic pain patients. Therapy dog visits were also able to improve emotional distress and f e e l i n g s o f w e l l – b e i n g i n f a m i l y a n d f r i e n d s accompanying patients to appointments and clinic staff (21). Pain relief interventions using AAT were made in several pediatric centers. Braun et al (22) investigated the change in pain and vital signs in an acute care pediatric center for children aged 3-17. The patients were divided into two groups: the first one (n=18) received AAT, while the second one (n=39) did not. The results provided strong evidence that AAT can reduce pain in children up to four times more than for the children who did not interacted with animals. The pain reduction felt by the children after 15 minutes of interaction with a dog was comparable with the use of oral acetaminophen with and without codeine in adults (22). In another study, Sobo et al (23) included 25 children aged 5 to 18 who underwent surgery and experienced post operative pain. Participants were offered one time visit form a therapy certified dog. The study findings suggested that dog assisted therapy may be useful as an adjuvant to the traditional pain treatment for children (23). Other medical fields were dog assisted therapy was successfully used were emergency departments (24) and military medicine (25).

Anxiety disorders and anxiety symptoms were among the first psychiatric fields where animal assisted therapy was used. Braker et al (5) conducted a study that included 230 patients with different psychiatric disorders, referred for therapeutic recreation sessions. A pre- and post treatment crossover study design was used to compare the effects of a single animal-assisted therapy session with those of a single regularly scheduled therapeutic recreation session. Before and after participating in the two types of sessions, subjects completed the state scale of the State-Trait Anxiety Inventory, a self-report measure of anxiety currently felt. The results revealed a statistically significant reduction in anxiety scores after the animal-assisted therapy session for patients with psychotic disorders, mood disorders, and other disorders, and after the therapeutic recreation session for patients with mood disorders (5). The same author, in a 2003 study tried to determine weather animal- assisted therapy (AAT) is associated with reductions in fear, anxiety, and depression in psychiatric patients before electroconvulsive therapy (ECT). In the study, 35 patients were assigned on alternate days to the treatment condition, consisting of a 15-minute AAT session, and the standard (comparison) condition, consisting of 15 minutes with magazines. Visual analogue scales were used to measure anxiety, fear, and depression before and after treatment and standard conditions. The results highlighted the fact that animal-assisted therapy may have a useful role in psychiatric and medical therapies in which the therapeutic procedure is inherently fear-inducing or has a negative societal perception (26). In another study with twelve acutely depressed patients, the authors measured state anxiety with the State-Trait Anxiety Inventory (STAI), a brief, easy-to-administer self-report measure that is widely used in research and clinical practice. The STAI state score was significantly reduced after the presence of a dog. This finding suggests that animal-assisted therapy causes highly significant reductions of state anxiety. Presence of dogs may offer an additional therapeutic benefit that might decrease anxiety and enhance psychotherapeutic strategies and motivation of patients and therapists (27). The recent study of Lang et al (28) included 14 acute schizophrenic patients. Each patient had to complete PANSS and the Spielberger State-Trait Anxiety Inventory before the canine sessions. STAI was completed again after the therapy. Two half hour sessions w e r e c o n d u c t e d w i t h e a c h p a t i e n t .
T h e psychotherapeutically approach consisted of a 30 minutes interaction with a dog and research assistant. During the control session the patients were assigned to a 30 minutes walk with the same research assistant. Both sessions took place in the same quiet room at approximately the same hour and the interval between the two sessions was one day. Results of the study showed reduced anxiety in acute schizophrenic patients as demonstrated by a significant decrease in STAI scores after the dog assisted session (28). The reduction of anxiety may be explained by evident changes in stress responsive biological parameters like cortisol and dopamine levels, blood pressure and heart rate, as observed after a 15 minutes interaction between certified therapeutically dogs and volunteers (29). The study of Chu et al (30) aimed of to evaluate the effects of animal-assisted activity on self-esteem, control over activities of daily living, and other psycho-physiological aspects among inpatients with schizophrenia. Thirty participants were randomly assigned to either the treatment or control group. A weekly animal-assisted activity program was arranged for patients in the treatment group for 2 months. A questionnaire assessing self- esteem, self-determination, social support, and psychiatric symptoms was completed the week before and the week after the animal-assisted activity. Compared with the control group, the treatment group showed significant improvement on all measures except for social support and negative psychiatric symptoms. The results of this study showed that animal-assisted activity can promote significant improvements in many clinical aspects among inpatients with schizophrenia. Therefore, animal-assisted activity should be integrated into the treatment of institutionalized patients with schizophrenia (30).
Another psychiatric domain where animal assisted therapy was applied is represented by the pathology of elderly. Several studies made upon patients with dementia were published during the last decade. Thus, the study of Richeson (31) focused on animal assisted therapy on agitated behaviors and social interventions for patients diagnosed with dementia. The design of the study was meant to test several hypotheses: if the effects of AAT can decrease agitated behavior in tested patients; if agitated behavior would suffer an increase after testing until follow up; if patients undergoing AAT would increase their social interactions and if AAT could decrease the need for medication. The study participants had to meet several including criteria among witch an established diagnosis of dementia with a MMSE score <15, previous documented agitated comportment, past interest in animals and no allergies to dogs or dislike of the animals. Results of the pilot study reported a decrease in agitation and a significant improvement of social interactions for the participants, even from the firs week of AAT. The fact that there was not a relationship between the cognitive level and the degree of agitated behavior suggested that AAT may be an appropriate intervention for moderate to severe cases of dementia. As far as the medication is concern, the study showed no need of decreased medication for the participants during AAT (31). The study of Motomura et al (32) assessed a small sample of patients with dementia (Alzheimer and vascular dementia) while undergoing therapy with certified trained dogs. The aspects followed were apathy, irritability, depressive symptoms and daily living activities. The most significant change after AAT was found on items for apathy scale. The recent review conducted by Barnabei et al (33) in 2012 included a number of 18 articles from literature with themes that concentrated upon the relationship between animal assisted interventions (AAI) and dementia patients. The review highlighted the effect of AAI on behavioral and psychological symptoms of dementia (BPSD), cognitive functions and depressive symptoms for patients diagnosed with dementia. For BPSD the studies included reported a decrease in irritability and anxiety items on the specific assessment instruments. Depressive symptoms and emotional liability evaluated with Geriatric Depression Scale were improved after animal-human interactions. For cognitive functions assessed with Mini Mental State Examination or Multidimensional Observation Scale for Elderly Subjects, an improvement was reported but it had no statistical significance. Only one of the study included in the review found a significant result (p<0,5) for spatial orientation, concentration and abstract thinking (33).
Pediatric psychiatry is also a domain where AAT has demonstrated its benefits. Katcher et al (34) examined the effect of animal assisted therapy for children diagnosed with attention deficit hyperactivity disorder (ADHD) and conduct disorders. 50 children were randomly assigned to an education program involving either interactions with animals or outdoor activities. The results outlined that the group of children who participated to animal assisted interventions showed an increased attendance, cooperation and engagement in learning activities, as well as a decreased in antisocial and violent behavior (34). Another good example for animal assisted therapy is seen in children with autism spectrum disorder (ASD). The review of O’Haire (35) discussed the results of two recent studies that included this pathology. In one study children were submitted to a 15 minutes therapy session with a dog, a stuffed dog or a ball. The sessions were held for 15 weeks. Results reported increased playfulness, focus and social awareness in the presence of the dog. The second study included horses and therapeutic horseback ridings for children with ASD for 12 weeks; its results indicated an increased sensory and social motivation and decreased inattention (35).

Animal assisted therapy has several benefits both in medical and psychiatric fields. The interactions between patients and trained animals resulted in lower levels of anxiety, reduced agitation, increased cognitive performances (attention), improved mood and increased social skills.

1.Delta Society. About animal assisted activity and animal assisted therapy. Online Available:http://www.deltasociety.org/aboutaat.htm
2.Beck A. Between Pets and People: the Importance of Animal Companionship. New York: Putnam, 1983. ISBN 0-399-12775-5
3.Schaefer K. Human-animal interactions as a therapeutic intervention. Counseling and Human Development 2002;34(5): 1-18.
4.Serpell J. Animal Companions and Human Well-Being: An Historical Exploration of the Value of Human-Animal Relationships. Handbook on Animal-Assisted Therapy: Theoretical Foundations and Guidelines for Practice 2000, 3–17.
5.Barker SB, Dawson KS. The Effects of Animal-Assisted Therapy on Anxiety Ratings of Hospitalized Psychiatric Patients. Psychiatr Serv 1998;49(6): 797–801. Retrieved 2012-03-18.
6.Wisdom JP, Saedi GA, Green CA. Another breed of “service” animals: STARS study findings about pet ownership and recovery from serious mental illness. Am J Orthopsychiatry 2009;79: 430–436.
7.Lefebvre SL, Gola GC, Christensen E et al. Guidelines for animal- assisted interventions in health care facilities. Am J Infect Control
2008;36: 78–85.
8.Allen K, Blascovich J, Tomaka J, Kelsey R. Presence of human friends and pet dogs as moderators of autonomic responses to stress in women. J Pers Soc Psychol 1991;61: 582–589
9.Wilson CC. Physiological responses of college students to a pet. J Nerv Ment Dis 1987;175: 606–612.
10.Friedmann E, Katcher AH, Thomas SA, Lynch JJ, Messent PR. Social interaction and blood pressure: influence of animal companions. J Nerv Ment Dis 1983;171(8): 461–464.
11.Allen K, Shykoff BE, Izzo JL Jr. Pet ownership, but not ACE inhibitor therapy, blunts home blood pressure responses to mental stress. Hypertension 2001;38(4): 815–820.
12.Friedmann E, Thomas SA. Pet ownership, social support, and one- year survival after acute myocardial infarction in the Cardiac Arrhythmia Suppression Trial (CAST). Am J Cardiol 1995;76(17): 1213–1217.
13.Friedmann E, Thomas SA, Stein PK, Kleiger RE. Relation between pet ownership and heart rate variability in patients with healed myocardial infarcts. Am J Cardiol 2003;91(6): 718–721.
14.Moser DK, Worster PL. Effect of psychosocial factors on physiologic outcomes in patients with heart failure. J Cardiovasc Nurs 2000;14: 106–115.
15.Piano MR, Kim SD, Jarvis C. Cellular events linked to cardiac remodeling in heart failure: targets for pharmacologic intervention. J Cardiovasc Nurs 2000;14: 1–23.
16.Chiariello M, Perrone-Filardi P. Pathophysiology of heart failure. Miner Electrolyte Metab 1999;25(1–2): 6–10.
17.Friedmann E, Thomas SA. Health benefits of pets for families. In: Marvin B, Sussman M (eds). Pets and the Family. New York, NY: Haworth Press, 1985, 191–203.
18.Katcher AH. Interactions between people and their pets: form and function. In: Fogle B (ed). Interrelationships Between People and Pets. Springfield, IL: Charles C Thomas Publisher, 1981, 41–67. Cole
19. KM, Gawlinski A, Steers N, Kotlerman J. Animal-Assisted Therapy in Patients Hospitalized With Heart Failure. Am J Crit Care 2007;16 (6):
20.Wolff AI, Frishman WH. Animal-assisted therapy in cardiovascular disease. Semin Integr Med 2005;2: 131-134.
21.Marcus DA, Bernstein CD, Constantin JM et al. Animal-assisted therapy at an outpatient pain management clinic. Pain Med 2012;13(1): 45-57.
22.Braun C, Stangler T, Narveson J, Pettingell S. Animal assisted therapy as a pain relief intervention for children. Complementary therapies in clinical practice 2009;15: 105-109.
23.Sobo EJ, Eng B, Kassity-Krich N. Canine visitation (pet) therapy. Pilot data on decreases in child pain intervention. Journal of holistic nursing 2006;24: 51-57.
24.Nahm N , Lubin J, Bankwitz KB et al. Therapy Dogs in the Emergency Department. West J Emerg Med 2012;13(4): 363–365.
25.Beck CE, Gonzales F Jr, Sells CH et al. The effects of animal-assisted therapy on wounded warriors in an Occupational Therapy Life Skills program. US Army Med Dep J 2012: 38-45.
26.Barker SB, Pandurangi AK, Best AM. Effects of animal-assisted therapy on patients’ anxiety, fear, and depression before ECT. J ECT 2003;19(1): 38-44.
27.Hoffman AOM, Lee AH, Wertenauer F et al. Dog-assisted intervention significantly reduces anxiety in hospitalized patients with major depression. Eur J Integr Med 2009;1(3): 145–148.
28.Lang UE, Jansen BJ, Wertenauer F et al. Reduced anxiety during dog assissted interviews in acute schizophrenic patients. Eur J Integr Med 2010;2: 123-127.
29.Odendaal JS, Meintjes RA. Neurophysiological correlates of affiliative behavior between humans and dogs. Vet J 2003;165: 296-301.
30.Chu CI, Liu CY, Sun CT, Lin J. The effect of animal-assisted activity on inpatients with schizophrenia. J Psychosoc Nurs Ment Health Serv
2009;47(12): 42-8.
31.Richeson NE. Effects of animal-assisted therapy on agitated behaviors and social interactions of older adults with dementia. Am J Alzheimers Dis Other Dem 2003;18: 353.
32.Motomura N, Yagi T, Ohyama H. Animal assisted therapy for people with dementia. Psychogeriatrics 2004;4(2): 40-42.
33.Bernabei V, De Ronchi D, La Ferla T et al. Animal-assisted interventions for elderly patients affected by dementia or psychiatric disorders: a review. J Psychiatr Res 2013;47(6): 762-73.
34.Katcher AH, Wilkins GG. The centaur’s lessons: therapeutic educations through care of animals and nature study. In: Fine AH (ed). Handbook of Animal Assisted -therapy: Theoretical Foundations and Guidelines for Practice. San Diego: Academic Press CA, 153-177.
35.O’Haire M. Companion animals and human health: Benefits, challenges, and the road ahead. Journal of Veterinary Behavior: Clinical Applications and Research 2010;5(5): 226-234.