Growing feelings of worthlessness and isolation led 30 percent of America's brightest teenagers to consider suicide, and 4 percent have tried it, a new poll shows.

The figure is the highest since "Who's Who Among American High School Students Annual Survey of High Achievers" started tracking suicide questions in 1984."It's important to note the statistics represent high-achievers, not the general teen population," Paul Krouse, publisher of "Who's Who Among American High School Students" in Lake Forrest, Ill., said in releasing the report Monday.

The poll taken last spring said blacks are at particular risk, noting that 10 percent of black high-achievers said they had tried suicide.

The number of teenagers who contemplated suicide has climbed from 28 to 30 percent since 1984, according to the 19th annual survey. The poll said the incidence of those trying to kill themselves increased from 3 to 4 percent during the same period, also the highest level in four years.

Of the major factors contributing to suicide, 86 percent blamed a feeling of personal worthlessness, 84 percent cited isolation and loneliness, 71 percent mentioned the pressure to achieve, 65 percent cited the fear of failure, 64 percent blamed drug and alcohol use and 63 percent cited a lack of communication with their parents.

The report is based on responses from 2,024 of the 575,00 high school juniors and seniors cited in the current teenagers' "Who's Who."

Highlights from the survey, with a margin of error of 2 percent plus or minus, include the following:

-Nearly half said they believe schools should issue condoms to help decrease teenage pregnancies or reduce the risk of AIDS; 30 percent did not.

-Seventy-five percent said they were virgins and 63 percent do not believe sex is an expected part of "going steady."