(WASHINGTON, Reuters)The risk of a heart attack jumps nearly fivefold during the first hour after smoking marijuana.

(路透社华盛顿电)开始抽大麻的一个小时之内，心脏病发作的危险性几乎会激增五倍。

this poses a particular threat to middle-aged users of the drug, especially those over age 45.

这种危险性对于中年的大麻吸食者特别严重，尤其是超过四十五岁的人。

The increased risk from marijuana was more dangerous than sexual intercourse for a sedentary person.

对于久坐的人而言，抽大麻所增加的危险性比性行为还高。

Marijuana can cause the heart rate to double.

大麻会让心跳速度增快一倍。