The study, which was presented at the International Stroke Conference, said that cats seemed to relieve stress and anxiety. The study lasted for nearly 10 years and involved 4,335 people who took part in the National Health and Nutrition Examination Study (NHANES II).

When the study began all participants, aged between 35 to 75 years, were free from coronary heart disease symptoms. Overall 55 percent of the participants owned cats.

The researchers led by Dr Adnan Qureshi, reported that they took into consideration confounding factors like age, gender, ethnicity/race, systolic blood pressure, cigarette smoking, diabetes mellitus, cholesterol levels and body mass index before concluding that cat owners had a 40 percent reduced risk of suffering from a fatal heart attack.

Some 3.4 percent of cat owners died from a heart attack during the study, while 5.8 percent of those who did not own a cat succumbed to a heart attack.

The researchers theorized that owning cats was in some way relaxing and helped reduce stress, which is one of the main causative factors in heart attacks.