Happiness in old age may have more to do with attitude than actual health, a new study suggests.

Researchers examined 500 Americans age 60 to 98 who live independently and had dealt with cancer, heart disease, diabetes, mental health conditions or a range of other problems. The participants rated their own degree of successful aging on scale of 1-10, with 10 being best.

Despite their ills, the average rating was 8.4.

"What is most interesting about this study is that people who think they are aging well are not necessarily the (healthiest) individuals," said lead researcher Dilip Jeste of the University of California at San Diego.

"In fact, optimism and effective coping styles were found to be more important to successfully aging than traditional measures of health and wellness," Jeste said. "These findings suggest that physical health is not the best indicator of successful aging—attitude is."

The finding may prove important for the medical community, which by traditional measures would have considered only 10 percent of the study members to be aging successfully.

"The commonly used criteria suggest that a person is aging well if they have a low level of disease and disability," Jeste said. "However, this study shows that self-perception about aging can be more important than the traditional success markers."

Health and happiness may indeed be largely in the mind. A study released last year found that people who described themselves as highly optimistic a decade ago had lower rates of death from cardiovascular disease and lower overall death rates than strong pessimists. Research earlier this year revealed that the sick and disabled are often as happy as anyone else.

The new study also showed that people who spent time each day socializing, reading or participating in other hobbies rated their aging satisfaction higher.

"For most people, worries about their future aging involve fear of physical infirmity, disease or disability," Jeste said. "However, this study is encouraging because it shows that the best predictors of successful aging are well within an individual's control."

The results, announced today, were reported at a meeting of the American College of Neuropsychopharmacology.

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