In 1975, researchers in England randomly gave retirees between the ages of 75 and 81 either a caged parakeet, or a potted begonia. They also evaluated the retirees psychological well-being, and their interest in, and attitudes toward other people. Over a three year period, those who receive the birds reported favorable changes overall. They had more friends, more visitors, and were more involved in their communities, compared with those who had received plants. The bird served as a focal point for communication with visitors. In addition, the retirees physical and psychological health evaluations improved. We know that the elderly are often at risk for social isolation, which can lead to depression, which in turn can affect physical health. Could keeping a bird as a pet really be the key to physical and mental health? In 1980, a team of researchers conducted a study of the effects of social isolation and support on survivors of heart attack. The researchers interviewed patients using questions that assess socioeconomic status, social networks, geographic mobility and living situation, along with psychological mood status. One question asked about pet ownership. A year later, the researchers followed up on the patients. They located all but two. Of the 92 remaining patients, 28 women and 64 men, 14 had died during the year, leaving 78 survivors. 53 of these survivors own pets. 28% of those who had pets survived for at least a year, compared to only 6% of non-pet owners. These first studies to examine the relationships between pets and human health sparked a lot of interest. In 1987, the National Institutes of Health held a workshop to assess the state of existing knowledge about the health benefits of pets. Experts from various disciplines reviewed the research on the roles of pets in five topical areas, including cardiovascular health, child development, the health and functioning of the elderly, therapeutic effects, and safety and risks in relationships between people and pets. The resulting report recommended increased research, particularly on the relationship between animals and the health of children and the elderly. It also recommended that the relationship between pets and cardiovascular disease be aggressively studied. Moreover, the report emphasized the need for rigorous statistical methodology in some studies. Sample sizes weren't large enough to support definitive conclusions. To increase the availability of reliable data, the report recommended that the US Census, as well as National Health surveys and epidemiological studies include questions about the number and type of animals in people's homes. It also called for more diversity within samples, especially with regard to socioeconomic status and race. This report effectively legitimized the research on pets and human health. Since 2010, nine studies per year on average have been published. The literature comes from various disciplines, but mostly from Madison Public Health and psychology. In this lesson and the next, I'll discuss the research on the benefits of ordinary pet keeping for physical and psychological health and well-being. There's a separate body of research on water called animal assisted interventions, or the goal directed use of animals as a specific part of a therapeutic treatment. This might include pet visitation in hospitals and nursing homes. But because it seems that we're always hearing that pets are good for people, I'm going to limit our discussion to what I'll call ordinary, quote unquote, pet keeping. Because of the importance of reducing cardiovascular disease, a large number of studies have focused on the role of pets in prevention and because stress in the form of increased blood pressure or heart rate can increase the risk for heart disease. Reducing it has implications for cardiovascular health. Some researches found an association between pet ownership and lower risk factors for cardiovascular disease. Pet owners have been found to have lower blood pressure, lower rates of smoking, and body mass index scores. Pet owners have been found to have lower rates of depression, and higher scores on physical quality of life. However, owning or caring for a pet of one's own might not be required. Studies have found that simply watching fish in an aquarium decreases diastolic blood pressure. You might be wondering whether it's that pets make people healthy, or that people who have pets are healthier to begin with? To test this, one study used participants who didn't have pets, but were willing to acquire them. Participants all worked as stockbrokers, and describe their jobs as highly stressful. They all lived alone. Moreover, they all had diagnosed stage two hypertension, and would soon begin treatment with medication to reduce it. The researchers randomly assigned their participants into those who would adopt pets, and those who would not. Although the medication lowered the blood pressure of all participants, those in the pet group had lower blood pressure increases under stress, compared to those without pets. Some of the most promising research on the benefits of pets for human health come from studies of dog ownership and physical activity. Overall, the research indicates that the exercise provided by dog walking provides cardiovascular, and other health benefits. In addition, dog walking offers opportunities to build social support through connections with other dog walkers. And the combination of pet ownership and social support appears to mediate depression and stress. On top of that, because canine obesity, obesity represents a growing veterinary health concern, more physical activity can benefit both sides of the human canine relationship. Most of the studies of the effects of pets on human health have involved dog ownership. But what about cats? Granted, if you're doing a study of physical activity, you're not going to get too many cats to go for walks. But what about ordinary cat ownership? Some research has done comparisons. Remember that study of the heart attack survivors? When it was replicated with a larger sample of patients, dog ownership, but not cat ownership, predicted one year survival after discharge. Another study also found that cat ownership predicted increased risk of death, or readmission to the hospital. Cat owners should not lose hope, however. More recent studies have found more promising results. Using large national representative samples, at least two studies have found a significantly lower risk for death following heart attack among previous, or present owners of cats, rather than dogs. So if you're hoping for good health and a long life, should you have a dog or a cat as a pet? To be on the safe side, why not both?
