CHICAGO (American Medical Association) -- Patients who described themselves as highly optimistic had lower risks of all-cause death, and lower rates of cardiovascular death than those with high levels of pessimism, according to an article in the November issue of The Archives of General Psychiatry, one of the JAMA/Archives journals.

According to the article, major depression is a known risk factor for cardiovascular death. However, the relationship between optimism and death has not received as much attention.

Erik J. Giltay, M.D., Ph.D., of Psychiatric Center GGZ Delfland, Delft, the Netherlands, and colleagues analyzed data from the Arnhem Elderly Study to test whether participants who are optimistic live longer than patients who are pessimistic.

Participants were aged 65 to 85 years (999 men and women) and completed a 30-item questionnaire on health, self-respect, morale, optimism and relationships. Of the participants, 941 (466 men, 475 women) had complete information on questions regarding optimism, and these patients were divided into four groups based on their level of optimism.

Over the follow up period of 9.1 years (1991 to 2001), there were 397 deaths. Compared to participants who reported a high level of pessimism, participants reporting high levels of optimism had a 55 percent lower risk of death from all causes, and a 23 percent lower risk of cardiovascular death.

The researchers also found an inverse relationship between level of optimism and risk of death, with a stronger protective effect of optimism in men than women for all-cause mortality, but not cardiovascular mortality.

"In conclusion, we found that the trait of optimism was an important long-term determinant of all-cause and cardiovascular mortality in elderly subjects independent of sociodemographic characteristics and cardiovascular risk factors," the authors write.

"A predisposition toward optimism seemed to provide a survival benefit in elderly subjects with relatively short life expectancies otherwise."

"Our results, combined with the finding that hopelessness was associated with an increased incidence or progression of disease, suggest that dispositional optimism affects the progression of cardiovascular disease," the researchers state.

"Although optimism reduces the risk of cardiovascular death through mechanisms largely unaffected by baseline values of physical activity, obesity, smoking, hypertension, and lipid profile, pessimistic subjects may be more prone to changes across time in risk factors that affect the progression of cardiovascular disease (e.g., the development of smoking habits, obesity, or hypertension) than optimistic subjects.

"Dispositional optimism may also be associated with better coping strategies that are adhered to throughout life."