Optimistic people are more likely to live longer, healthier lives than pessimists, according to a new study.  Researchers at

University of Pittsburgh looked at death rate and chronic health conditions among participants of the Women's Health Initiative study, which has followed more than 100,000 women aged 50 and over since 1994.   Women who were optimistic -- those who expect good rather than bad things to happen -- were 14 percent less likely to die from any cause than pessimists and 30 percent less likely to die from heart disease after eight years of follow up in the study.   Optimists also were also less likely to have high blood pressure, diabetes or smoke cigarettes.   The team, led by Dr. Hilary Tindle, also looked at women who were highly mistrustful of other people -- a group they called "cynically hostile" -- and compared them with women who were more trusting.   Women in the cynically hostile group tended to agree with questions such as: "I've often had to take orders from someone who didn't know as much as I did" or "It's safest to trust nobody," Tindle said in a telephone interview.   "These questions prove a general mistrust of people," said Tindle, who presented her study Thursday at the American Psychosomatic Society's annual meeting in Chicago.   That kind of thinking takes a toll.  "Cynically hostile women were 16 percent more likely to die (during the study period) compared to women who were the least cynically hostile," Tindle said.  They were also 23 percent more likely to die from cancer.