Awaiting surgery is a distressing experience for most breast cancer patients.[1-3] It has been described as a acute, short-term stressor with multiple stressful components such as concerns regarding one’s physical condition, postoperative recovery, hospital admissions, anticipating painful procedures, image problems, confronting cancer diagnosis and worries about survival and recovery.[4] It is known that such concerns evoke strong emotional and psychological reactions in the subjects further heightening preoperative distress. Such heightened preoperative distress has been found to be related to longer hospital stays, delayed recovery, more postoperative complications, pain and increased need for medications.[4,5] These distressing symptoms are also known to impair local and
systemic immune responses leading to delayed wound repair[6,7] and postoperative infections.[8,9] Apart from direct effects on endocrine and immune function, greater pain sensitivity and distress of more anxious patients may affect recovery because of reduced compliance; for example, breathing exercises reduce the risk of pneumonia following surgery.[10] Patients may become more cautious about following recommendations for walking, breathing or coughing because of pain and distress further affecting the process of recovery.[5]
A multitude of factors seem to affect antitumor and innate immune responses collectively during surgical recovery such as mood, perceived stress, anti-inflammatory analgesics and anesthesia. Medications that reduce pain and distress such as analgesics,[11] corticosteroids, morphine[12] and anesthetics[13,14] following surgery can directly help reduce treatment-related distress, improve functional well being and reduce consequent immune suppression. However, such medications are not always cost-effective and have side effects ranging from gastrointestinal distress, nausea and, sleep disturbances[10] and also excessive use can dampen both innate and anti-tumor immune responses.[4] For example, marked suppression of NK cell activity and count is observed following surgical procedures that often last for an extended period inspite of the use of anti-inflammatory and anesthetic medications.[15] This transitory dysfunction of NK cells may create a favourable milieu for metastases.
This has been attributed to loss of control over dormant micrometastases or from an inability to destroy tumor cells released perioperatively.[16] Moreover, changes in NK cell activity and number seem to be affected by mood states with decreased NK cell numbers seen with depressed mood[17,18] and decreased NK cell activity is related to anxiety states.[19] There is evidence to show that interventions that alter appraisal, coping and/or mood may also modulate
immune and endocrine function, thereby enhancing surgical recovery.[20,21] Even modest interventions that have relatively small consequences for psychological distress such as educating the patient about surgery[22] and improving the ambience in the wards[23] are known to influence the recovery process. Several meta-analyses of presurgical intervention studies have argued that association between presurgical intervention and clinical outcome is clinically meaningful.[24] Depending on the meta-analysis, two thirds to three quarters of intervention patients had better outcomes than control subjects with the size of improvement ranging from 20–28%.[24] These stress reduction and behavioral interventions apart from reducing distress, are also known to affect immune
responses in general.[25,26] Yoga is one such psychotherapeutic intervention, which, has been used effectively in numerous health care conditions where stress was believed to play a role. General effects of yoga in promoting health are due to its ability to establish stable autonomic balance,[27] development of hypometabolic states,[28] improvement of physical efficiency,[29] improvement of thermoregulatory efficiency,[30] increase in cardiopulmory functions,[31]
improved immunological tolerance,[32] neuro-endocronine functions,[33-35] improved mood states[36-38] and a tranquil state of mind to combat stress.[39] These physiological benefits possibly explain the rationale for using yoga intervention to reduce distress and improve immune outcomes in cancer subjects undergoing surgery. Moreover, various techniques of yoga have shown to improve mood states, reduce stress, improve quality of life and, adjustment
in cancer patients.[40] In an earlier study, we have shown yoga to reduce treatment-related distress and symptoms in breast cancer patients undergoing chemotherapy.[41] This may have implications in the current context wherein high psychological distress is seen preoperatively. We hypothesize that yoga interventions would help reduce psychological distress and improve anti-tumor immune responses in breast cancer patients following surgery.