Suicide is the second leading cause of death in people between the ages of 15 to 34 in the United States, according to a new study from the Centers for Disease Control (CDC).Suicide is the second leading cause of death in people between the ages of 15 to 34 in the United States, according to a new study from the Centers for Disease Control (CDC).Suicide is the second leading cause of death in people between the ages of 15 to 34 in the United States, according to a new study from the Centers for Disease Control (CDC).