Aging and many diseased states have been shown to be associated with depressed vagal activity.The extent of vagal depression correlates with the severity and poor prognosis of the disease.

• 摘要老化与疾病均会导致副交感神经活性的下降，而且副交感神经活性下降的程度与疾病严重度或预后有关，如果有生理性的副交感神经活性加强法，则值得推荐给病人。