Dogs are better at relaxing heart-failure patients than people are, a new study found.

"Dogs are a great comfort," says study leader Kathie Cole of UCLA Medical Center. "They make people happier, calmer and feel more loved. That is huge when you are scared and not feeling well."

Researchers studied 76 people hospitalized with heart failure. Each got either a 12-minute visit from a human volunteer or a human volunteer and a dog. A control group got no visit.

The dogs were specially trained to lie on the bed and interact with the patient.

The scientists monitored the patients' blood pressures, releases of harmful hormones and other measurables that characterize heart failure. Anxiety tests were done before and after the session.

Anxiety scores dropped 24 percent among patients interacting with a dog. Scores dropped 10 percent when only a human visited. The group that got no visit exhibited no change.

Dogs helped cause a 17 percent drop in a stress hormone called epinephrine, while human visitors could muster only a 2 percent dip. The hormone level rose 7 percent, on average, in the group that got no visitor.

Similar improvements were seen in other measures.

"This study demonstrates that even a short-term exposure to dogs has beneficial physiological and psychosocial effects on patients who want it," Cole said. "This therapy warrants serious consideration as an adjunct to medical therapy in hospitalized heart failure patients."

The study, announced today, is detailed in the American Heart Association's Scientific Sessions 2005.

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