New York - Optimists may enjoy longer lives than people with a dimmer outlook on the future, a long-term study suggests.

Researchers found that of nearly 7,000 adults followed since their college days in the 1960s, those who were optimistic in their youth had a lower risk of dying over the next 40 years than their more pessimistic peers.

On average, the most pessimistic study participants were 42 percent more likely to die of any cause than the most positive participants, according to findings published in the Mayo Clinic Proceedings medical journal.

The results echo those of a number of past studies on personality factors and health, including research that has linked optimism to longer life. One study of elderly adults found that those with a positive view of the future were less likely than pessimists to die over the next decade -- regardless of their health at the start of the study.

The current findings could be explained by any number of factors, according to the study authors, led by Dr. Beverly H. Brummett of Duke University Medical Center in Durham, North Carolina.

For example, they say, optimists are less likely to suffer from depression than are pessimists, which could, in turn, affect their physical health. They may also maintain a healthier lifestyle, paying more attention to their diet and exercise habits.

These latest findings are based on a 40-year follow-up of 6,958 men and women who entered the University of North Carolina, Chapel Hill in the mid-1960s. At the time, they took a standard personality test that gauges a person's tendency to be optimistic or pessimistic.

In general, optimists believe negative events are only temporary and don't let them affect their overall attitude about themselves and the world. Pessimists, in contrast, take such events to heart, often blaming themselves and believing that the bad times will last forever.

In this study, 1,630 were deemed pessimists and 923 optimists, while most were judged to be somewhere between a pure optimist or pessimist.

If pessimism is a risk factor for premature death, that begs the question of whether anything can be done about it.

It is difficult to change the basic constructs of your personality, Brummett told Reuters Health. However, she added, "there are many aspects of personality that can be modified to a certain degree if an individual is motivated to do so."

For example, Brummett said, people with a hostile temperament -- a trait linked to heart disease and premature death -- may be able to change their ways with the help of anger management therapy.

On the other side of the spectrum, people might try injecting some positivity into their lives. As an example, Brummett pointed to meditation, which, according to some research, may boost positive emotions.