When Oklahoma banned smoking in restaurants a few years ago, the intent was to keep employees and patrons from having to deal with second-hand smoke. Critics said the impact would be insignificant.

State lawmakers relied on studies which linked smoking bans to decreased heart attacks. Another study released this week supports earlier studies.

A three-year study in Pueblo, Colo., found a 41 percent drop in heart attack hospitalization after a workplace smoking ban. It's one of nine studies that have linked smoking bans to decreased heart attacks.

The Associated Press reports the rate of heart attacks in Pueblo dropped from 257 per 100,000 people to 152 per 100,000 three years after the 2003 ban was instituted.

Researchers at the Centers for Disease Control in Atlanta say second-hand smoke causes about 46,000 heart disease deaths and about 3,000 lung cancer deaths among non-smokers annually.