By ALEX SILVERMAN
KIRO Radio

Across the country, folks are living longer these days. But in Seattle, the average life expectancy has soared the past few years. In fact, the Emerald City has one of the longest-living populations in the world.

"If we in Seattle were an independent nation, our life expectancy would rank second in the world behind only Japan," said Clark Williams-Derry, head researcher for the non-profit Sightline Insititute.

"Sometime in the middle of the 1990s, we saw an incredible surge, where Seattle's life expectancy shot ahead of the state as a whole," he said.

The average Seattleite now lives to 83, the average Washingtonian to around 80.

Williams-Derry wanted to know what Seattle's secret is. With help from the King County Health Department, he found an answer.

"When effective anti-retroviral treatment for AIDS became available, life expectancy in Seattle soared," Williams-Derry said.

That happened in 1996. "What we saw was a dramatic decrease in the number of illnesses and deaths that were AIDS-related," said David Emerson with the Lifeline AIDS Alliance.

Seventy-seven percent of King County HIV's deaths were reported in Seattle in the early 1990s, so when the cocktail took a swing at AIDS, Seattle's life expectancy overtook the state's.

"It's a fantastic story about a medical advance that had a huge impact on the overall health of the population" Williams-Derry said.

But it doesn't really explain why Seattle's life expectancy continued to grow dramatically into the 2000s. Reduced smoking, improved public health policies, growing wealth, and other factors may have contributed, Williams-Derry said.

Read Sightline's full report.

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