THURSDAY, April 4, 2019 (HealthDay News) -- If a few minutes of your time could save a person's life, would you do it?

In a new study, researchers found that any type of bystander CPR -- including just performing chest compressions -- significantly improves the chances of survival for people who suffer an out-of-hospital cardiac arrest.

A cardiac arrest is when your heart suddenly stops beating.

"Bystanders have an important role in out-of-hospital cardiac arrest. Their actions can be lifesaving," said study first author Dr. Gabriel Riva. He's a Ph.D. student at the Karolinska Institute in Stockholm.

Standard CPR involves chest compressions and mouth-to-mouth breathing. But hands-only CPR is becoming more widespread, so researchers wanted to compare 30-day survival rates for the two methods.

The researchers analyzed data on more than 30,000 people in Sweden who suffered out-of-hospital cardiac arrest during three time periods: 2000-2005, 2006-2010 and 2011-2017. Over those three periods, 39% received standard CPR and 20% received hands-only CPR.

During the study period, hands-only CPR was gradually adopted into Sweden's CPR guidelines.

Bystander CPR rates rose from 41% in 2000-2005 to just over 68% in 2011-2017.

Standard CPR rates were about 35% in the first period, and 38% in the third period, the findings showed.

Hands-only CPR rates rose from about 5% in the first time period to 14% in the second, and then to 30% in the third period -- an overall sixfold increase, the study authors noted.

During the 18-year study, patients receiving standard and hands-only CPR were twice as likely to survive 30 days as patients who received no CPR, according to the report published online April 1 in the journal Circulation.

"We found a significantly higher CPR rate for each year, which was associated with higher rates of compression-only CPR," Riva said in a journal news release.

"CPR in its simplest form is just chest compressions. Doing only chest compressions doubles the chance of survival, compared to doing nothing," Riva explained.

Cardiac arrest is a leading cause of death, the American Heart Association (AHA) says. It is often fatal if no immediate action is taken. Each year, there are more than 325,000 out-of-hospital cardiac arrests in the United States.

If you witness a cardiac arrest, the AHA recommends that you call 911 (or ask someone else to call) and begin to push hard and fast in the center of the person's chest until help arrives. Push at a rate of 100 to 120 compressions per minute, which corresponds to the beat of the song "Stayin' Alive" by the Bee Gees.