∗University of Texas
†University of Missouri
Human/animal interactions (HAI) have become an important part of the lives of many people of all ages. While many who engage in HAI believe in its usefulness, only in the last two decades have there been numerous studies that provide research data to support its beneficial effects, both physiological and psychosocial.
The increasing numbers of elderly and their longevity are supported by census data in many countries. While people are living longer and are in better health than in previous centuries, a number of elderly persons may be living at least part of their lives alone, having lost the companionship of spouses, children, other family members, and friends for a variety of reasons. While it is not suggested that animals can replace human family and friends, there are now data to support the fact that HAI can lessen the loneliness, reduce physiologic arousal, increase health behaviors, such as walking and other exercise, and improve the psychosocial status of many elderly persons. In addition, HAI has improved the lives of institutionalized elderly, both those who are cognitively intact and those with impaired cognitive ability.
15.2 Human companion/animal interactions and successful aging
Research has demonstrated that physiologic arousal lowers in response to human/companion animal interaction. Early research showed lowering of blood pressure when people interacted with dogs to which they were attached (Baun et al., 1984). More recently, Odendaal (2000) found that stress hormone (cortisol) levels decreased most when people quietly interacted with their own pet dog. Cortisol levels also decreased (but less) when people interacted with an unfamiliar, but friendly dog. Elevated cortisol levels have been linked with memory loss (Greendale et al., 2000) and as one component of “allostatic load,” in which the body develops cumulative effects of repeated adaptations to stressors (Seeman et al., 1997). Allostatic load has been associated with overall physical and cognitive decline in older adults (ibid.)
Interacting with a companion animal may be one way to reduce allostatic load. Allen et al. (2002) found that people had significantly smaller increases in blood pressure and heart rate when a dog was present while they completed arithmetic tasks and that pet owners had significantly lower blood pressure and heart rate levels than non-pet owners to begin with. Hertstein (1995) found that pet saliency or importance was a significant predictor of physical health in older adults.
Walking is one exercise in which many elderly persons participate. In a study of 394 elderly, dog walkers were more likely to achieve more time walking and at a faster pace than non-dog walkers (Thorpe et al., 2006). Dembicki and Anderson (1996) found that older adult pet owners walked longer and also had lower triglyceride and cholesterol levels than non-pet owners. Also, during dog walking, elderly volunteers were able to increase the high-frequency power values of heart rate variability, a measure of parasympathetic neural activity which potentially has a greater health benefit as a buffer against stress, than walking without a dog and that this benefit was sustained during dog walking (Motooka et al., 2006). But even more important was that this relaxation response was cumulative over additional dog walks.
Recently, dog ownership and dog walking were associated with having and maintaining over a three-year period, faster normal and rapid walking speeds in older adults (Thorpe et al., 2006). Based on these findings, dog walking may have an impact on preventing disability and functionally limiting effects of chronic illnesses.
Commitment to pets—particularly dogs—involves exercising them, and thus may lead to healthier exercise patterns among dog owners, but these patterns may differ across ethnic groups. For example, Johnson and Meadows (2002) found that while Latino elders expressed a very strong bond with their pet dogs, they did not necessarily exercise with them.
Other investigators have found that pets influence older adults’ health indirectly by improving morale (Lago et al., 1989). This mind/body connection has been well established in research and can be a factor in maintaining older adults’ health and preventing or minimizing disability. There is reason to believe that older adults’ interaction with companion animals may activate this connection and be a powerful tool for health care providers, family members and older adults themselves in promoting successful aging by preventing chronic illnesses, or when they do occur, by minimizing their disabling effects. For example, elderly women having a pet to which they were attached were more likely to report higher levels of happiness than those who either did not have a pet or were not attached to their pets (Ory and Goldberg, 1983). This effect of pets, however, was related to the socioeconomic status (SES) of the women with those of higher SES having higher levels of happiness than those of lower SES.
In health care settings, companion animals have been found to be beneficial in many ways. For example, animal-assisted therapy in an oncology day hospital with elderly patients undergoing chemotherapy resulted in decreased depression compared with control subjects who did not have a dog present (Orlandi et al., 2007). In a study of the utility of a pet animal in the treatment of clinical depression in a nursing home, a significant reduction in depression was found in both the pet therapy and conventional therapy groups but not in the control no therapy group (Brickel, 1984). Likewise, elderly persons hospitalized for short-term rehabilitation experienced less depression when a caged bird was placed in their rooms for 7 days (Jesson et al., 1996).
Among the institutionalized elderly, animals have also been found to be therapeutic. Residents of two long-term care facilities showed significant positive changes in mood for those receiving visits from volunteers with a dog as compared to those without a dog (Lutwack-Bloom et al., 2005). Likewise, residents in long-term care facilities had less loneliness when receiving animal-assisted therapy (AAT) than those not receiving AAT (Banks and Banks, 2002).
The presence of therapy animals has been particularly useful in reducing agitated behaviors (Churchill et al., 1999, Richeson, 2003), in decreasing episodes of verbal aggression and anxiety (Fritz et al., 1995) and in increasing social interaction (Fick, 1993; Kongable et al., 1989) in institutionalized elderly with dementias, including Alzheimer’s disease. Even visiting with a robotic dog has been found to be beneficial to well-being among nursing home residents (Banks et al., 2008).
Aquariums have had interesting effects on persons with Alzheimer’s disease. Edwards and Beck (2002) demonstrated significant increases in nutritional intake among residents of specialized Alzheimer’s units by simply placing aquariums in the dining rooms. The increases in nutrition were accompanied by significant weight gain among the residents.
Using “Living Habitat,” in which plants and animals were introduced to a nursing home, a sample of residents had higher cognitive status and became more positively engaged with their environment but with a decreased sense of control after six months. Residents who had greater affinity for pets also became more positively engaged with their environment (Ruckdeschel and Van Haitsma, 2001).
While many areas of companion/animal interaction with elderly need further research to substantiate their effectiveness, there are studies to support positive benefits from this intervention. These interventions, however, need to be planned carefully considering not only characteristics of the elderly themselves but also of their environment. We present in Box 15.1 a case study of dog visitation to newly admitted nursing home residents.
Box 15.1 Effects of Dog Visitation on Newly Admitted Older Adult Nursing Home Residents
The purpose of this research was to conduct a case study of one nursing home in which a three-group, delayed treatment, pre-test post-test design was used to test the effectiveness of a dog visit protocol (DVP) on mood, social support, sense of coherence, and stress (measured via salivary cortisol). Fifteen older adults who had relocated to a nursing home in the preceding four weeks for long-term residence and scored 3 or higher on the Short Mini Mental State Exam (SMMSE) were included in the study. Participants who were moving from another nursing home were not included. Three groups were created: an experimental group who received dog visits (n = 5), an experimental group who received friendly person visits (n = 5), and a control group who received standard care (n = 5).
The first five residents to consent were assigned to the control group and were given the usual admission procedures of the facility, the next five were assigned to the dog visit group, and the final five were assigned to the human visit group. Experimental group participants received either 18 visits from a trained, certified visitor dog and its handler, or 18 visits from a human visitor, over a six-week period (three visits per week). Each visit consisted of a 20-minute session in the participant’s room.
The dog used for the study was certified by the University of Missouri-Columbia College of Veterinary Medicine’s Pet Assisted Love and Support (PALS) program. The dog handler was fully oriented to the study protocols. The handler was instructed to discuss only the dog during the visits. At the initial visit, handlers explained that visits could involve combing, petting, and talking to the dog. No lively play (e.g. throwing a ball, wrestling, etc.) was permitted.
After informed consent, all participants completed the Short Mini Mental State Exam (SMMSE), a Demographic Questionnaire (DQ), the Profile of Mood States (POMS), the UCLA Loneliness Scale (UCLA), the Social Provisions Scale (SPS), the Daily Hassles and Uplifts Scale (DHUS), and the Orientation to Life Questionnaire, a measure of sense of coherence (OTLQ). Saliva samples were collected at 8 am and 4 pm by having the older adults spit into a prepared collection tube. Post-protocol data collection occurred within one week after the experimental group participants completed their 18th dog visit or human visit. This data collection occurred during the seventh week of residence for the control group. All participants then completed the POMS, UCLA, SPS, DHUS, and OTLQ once again. Saliva samples were again collected from all participants at 8 am and 4 pm using the same method as in the pre-test. Experimental group participants also completed the Exit Questionnaire. Table 15.1 shows demographic characteristics of the sample.
|Total (n = 15)||Control group (n = 5)||Dog visit group (n = 5)||Human visit group (n = 5)|
|Age||78.3 (s.d. = 12.4)||83.8 (s.d. = 10.0)||74.8 (s.d. = 13.7)||76.4 (s.d. = 13.9)|
|Male||7 (46.7)||1 (20)||4 (80)||2 (40)|
|White||14 (93)||4 (80)||5 (100)||5 (100)|
|Married||1 (7)||0||1 (20)||0|
|Single||1 (7)||0||1 (20)||0|
|Divorced||4 (28)||1 (20)||1 (20)||3 (60)|
|Separated/widowed||8 (57.1)||4 (80)||2 (40)||2 (40)|
|Education no H.S.||3 (20)||1 (20)||1 (20)||1 (20)|
|Some H.S.||4 (26.7)||1 (20)||2 (40)||1 (20)|
|H.S. graduate||3 (20)||0||1 (20)||2 (40)|
|Some college||2 (13.3)||0||1 (20)||1 (20)|
|Bachelor’s||2 (13.3)||2 (40)||0||0|
|Graduate work||1 (6.7)||1 (20)||0||0|
Note: Percentages in parentheses.
For each group, T-tests were performed to detect significant differences between pre-test and post-test scores. Results (shown in Table 15.2) are reported in terms of difference scores (pre-post) and indicated that the control group had fewer uplifts and less social integration after the six-week study period. The human visit group had less depression and lower cortisol levels after the six-week study period. The dog group had no significant changes in any outcome measures. However, results were in expected directions including less loneliness, tension, depression, anger, and confusion.
|Control group||Dog visit group||Human visit group|
|Reassurance of worth||−1.00||1.00||−0.20|
|UCLA Loneliness Scale||0.20||0.20||0|
|Orientation to life||−2.60||0||0.40|
|Difference between a.m. scores (post-pre)||−0.03||0||0|
|Difference between p.m. scores (post-pre)||0.02||0.01||0.01∗|
|Difference between p.m-a.m.||−0.01||0.01||0|
∗ Note: p <0 .10.
Using the Kruskall-Wallis test, group mean cortisol am, pm, and the daily averages were compared for the three groups. At alpha level of 0.05 there were no statistically significant differences in cortisol levels between groups. However, the human visit group had a significantly higher post-pm cortisol level, indicating a greater level of stress after the six weeks.
The Kruskal-Wallis test was used to compare sense of coherence and mood across the three groups. Displayed results (shown in Table 15.3) indicated that at the pre-test, the dog visit group had a significantly higher sense of coherence, and stronger reassurance of worth pre score than the control group. The dog group had significantly less anger than the control group. The human visit group had a stronger sense of coherence and reassurance of worth, and less anger than the control group.
|Control||Dog visit||Human visit||Control||Dog visit||Human visit|
|Hassles||8.60 (6.42)||14.40 (4.50)||13.40 (0.54)||4.80∗ (3.34)||12.80∗ (1.64)||12.60 (1.81)|
|Uplifts||15.60 (9.28)||18.00(3.74)||17.80 (3.11)||11.60∗ (7.43)||19.80∗ (1.30)||19.20 (3.83)|
|POMS Tension||6.00 (4.06)||5.00 (6.36)||4.40 (3.04)||7.80 (6.37)||1.20 (0.83)||2.60 (2.70)|
|Vigor||14.20 (11.34)||3.20 (3.34)||1.60 (1.51)||5.60 (7.82)||1.600 (1.94)||0.60∗ (1.34)|
|Fatigue||8.80 (7.29)||0.60∗ (1.34)||0.40∗ (0.54)||3.40 (4.44)||0.0||0.20 (0.44)|
|Confusion||5.00 (3.80)||22.60 (2.96)||17.40 (5.02)||16.00 (11.93)||21.40 (3.71)||17.20 (4.76)|
|Mood||2.20 (30.78)||3.00 (4.52)||1.60 (1.67)||6.00 (8.68)||0.60 (1.34)||0.80 (0.83)|
|Depression||9.20 (9.57)||2.80 (0.83)||3.20 (0.83)||4.20 (3.76)||2.60 (1.81)||1.80 (1.30)|
|Anger||7.40∗∗ (7.43)||−8.00 (16.21)||−6.20 (9.67)||11.00 (3.94)||−15.40 (8.64)||−11.20 (8.95)|
|Social provisions Attachment||6.20 (3.56)||7.60 (2.30)||8.20 (1.09)||6.60 (3.78)||7.40 (0.89)||8.00 (0.00)|
|Social integration||4.80 (2.77)||6.40 (1.14)||6.00 (0.70)||4.20 2.48||5.80 (0.83)||6.60 (1.34)|
|Reassurance of worth||3.80∗∗ (2.38)||7.80∗ (1.48)||6.40 (0.89)||4.80 (3.03)||6.80 (1.30)||6.60 (0.54)|
|Reliable alliance||5.60∗∗ (3.57)||6.40 (0.89)||6.40 (0.89)||5.60 (3.20)||6.00 (0.00)||5.60 (0.89)|
|Guidance||4.80 (2.94)||6.40 (0.54)||6.40 (1.14)||4.80 (2.68)||6.40 (0.89)||6.00 (0.00)|
|Opportunity||5.40 (3.20)||4.00 (1.22)||4.00 (0.70)||4.80 (2.77)||4.00 (0.70)||3.80 (1.09)|
|UCLA Loneliness Scale||3.40 (2.07)||4.20 (0.44)||4.00 (0.00)||3.20 (2.16)||4.00 (0.00)||4.00 (0.00)|
|Orientation to life||5.60∗ (3.57)||9.40∗ (1.14)||9.80∗ (0.83)||8.20 (4.76)||9.40 (0.54)||9.40 (0.54)|
∗ Note: p <0 .10,
∗∗ p <0 .05. Standard deviations in parentheses.
However, on the post-test scores, both the human and the dog visit group had significantly more uplifts than the control group. The dog visit group had more uplifts and less anger. The human visit group had more uplifts and less depression than the control group. There were no significant differences between the dog and human visit groups.