9.12 Complementary therapies in pain management

Pain is one of the most important symptoms that compromise patients’ quality of life (QOL). Appropriate and adequate pain management remains challenging because pharmacologic treatment, the mainstay of pain management, does not always meet patients’ needs and may produce difficult side effects. Interventional approaches, such as neuraxial analgesia and neuroablative techniques, and disease-modifying therapies, such as radiotherapy, are sometimes useful, but often are unavailable or contrary to the goals of care (Cherny, 2004).

The medical treatment of pain requires continuing effort to balance analgesic effects while minimizing adverse effects (Cherny, 2000; Paice and Ferrell, 2011).Opioid side effects are very common, particularly gastrointestinal effects (e.g. constipation, nausea, and emesis) and somnolence or cognitive impairment. Despite the many strategies that may be used to improve the balance between analgesia and side effects, such balance may not always be achievable (Cherny and Portenoy, 1994; McNicol et al., 2003).

Complementary therapies offer additional treatment options that are not traditionally part of Western medical care but can be incorporated into a multimodality care plan. Some of these therapies have demonstrated a favourable benefit:risk ratio in recent research and are increasingly used as adjunct therapies integrated into mainstream care. Clinicians who manage pain in populations with serious or life-threatening illness should understand the current state of evidence for complementary modalities, such as mind–body therapies, acupuncture, and massage therapy, and should be able to make recommendations for clinical practice.

In general, complementary therapies reduce pain by interfering with the processing of pain signals. Mind–body therapies reduce the perception of pain by affecting psychological factors, such as anxiety or depressed mood, that can increase pain intensity or worsen the impact of pain on QOL. Neurophysiology and neuroimaging studies since the 1970s provide evidence that the analgesic effect of acupuncture is likely mediated via modulation of endogenous opioid and other neurotransmitter pathways, activities in the limbic system of the brain, and the processing of pain signals in the central nervous system (Napadow et al., 2008; Han, 2011). The array of symptoms relieved by massage therapies points to both positive local effects on soft tissue, as well as subconscious mechanisms that control the experience of pain and emotions (Sagar et al., 2007).

Mind–body therapies are defined as practices that focus on the interactions among the brain, mind, body, and behaviour, with the intent to use the mind to affect physical functioning and promote health (National Center for Complementary and Alternative Medicine, 2012). The most common symptoms that people turn to these therapies for are pain, dyspnoea, and fatigue (Wells et al., 2007). Mind–body therapies encompass a wide variety of specific therapies, such as hypnosis, meditation, yoga/qigong (which also has physical movement components), and music therapy.

Hypnosis is a practice by which a therapist induces, or instructs the patient on how to self-induce, a mental state of focused attention or altered consciousness between wakefulness and sleep. In this state, distractions are blocked, allowing the patient to concentrate intently on a particular subject, memory, sensation, or problem. Patients may receive suggestions, or self-suggest, changes in perceptions toward sensations, thoughts, and behaviours. In a systematic review of 21 studies (11 randomized controlled trials (RCTs), two non-RCTs, and eight case series), self-hypnosis provided pain relief in cancer patients and dying patients (Pan et al., 2000). However, a subsequent systematic review of 27 reports (one RCT, 24 case studies, and two other types of studies) concluded that the poor quality of studies evaluated, and the heterogeneity of study populations, limited further evaluation (Rajasekaran et al., 2005). More recently, a meta-analysis of 37 studies (N = 4199) on psychosocial interventions, including hypnosis, concluded that these modalities have a significant medium-size effect on both pain severity and pain interference with functioning, and that quality-controlled psychosocial interventions should be considered in multimodal approaches to pain management for cancer patients (Sheinfeld Gorin et al., 2012).

Importantly, there appears to be a widespread acceptance among the general public to consider the use of hypnosis to control side effects associated with cancer treatment (Sohl et al., 2010). This willingness to participate may in fact have an added impact. In a RCT evaluating a hypnotherapy intervention in a sample of patients with metastatic breast cancer (N = 124), the intervention group had significantly less increase in the intensity of pain and suffering over time, and highly hypnotizable participants reported greater benefits from hypnosis, employed self-hypnosis more often outside of group therapy, and used it to manage other symptoms in addition to pain (Butler et al., 2009).

Meditation involves practices that invite heightened awareness and attention to one’s own sensations, surroundings, and/or inner mental processes. A particular type of meditation, mindfulness-based stress reduction (MBSR), provides the practitioner with the opportunity to develop an objective ‘observer role’ for emotions, feelings, and perceptions, and to create a non-judgemental ‘mindful state’ of conscious awareness. A meta-analysis of four RCTs and six observational studies totalling 583 participants showed that MBSR is beneficial for mood, anxiety, depression, and QOL in general, although not so much for pain specifically (Ledesma and Kumano, 2009). Several systematic reviews show similar findings (Smith et al., 2005; Matchim and Armer, 2007; Shennan et al., 2011).

Yoga and qigong are practices that combine physical movement, breath control, and meditative components. Yoga has been found to significantly improve anxiety, depression, distress, and stress in a meta-analysis of ten RCTs (Lin et al., 2011). RCTs evaluating pain as the primary end point in a palliative care setting are lacking. Similarly, qigong was found promising for stress reduction and improving QOL, but no strong data support its efficacy in treating pain specifically (Chan et al., 2012).

Music therapy takes advantage of the profound effect of music on a patient’s emotional and spiritual state. Patients may listen to or participate in the performance of music and singing. There are a large number of qualitative studies demonstrating the benefit of music therapy in reducing pain and anxiety (Hilliard, 2005). A recent RCT that tested music therapist-guided autogenic relaxation and live music in 200 palliative care patients showed a significant decrease in pain scores (Gutgsell et al., 2013).

In general, mind–body therapies have the most benefit in reducing psychological complications from pain, or anxiety and distress that exacerbate the impact of pain on patients, rather than the pain itself. The side effect risk is low and most of these practices can be taught to patients for self-practice. Mind–body therapies should be considered for palliative care patients who are experiencing anxiety, distress, or sleep and mood disturbance in addition to pain.

Acupuncture, a modality originating from Traditional Chinese Medicine, involves the insertion of needles into certain points on the body followed by stimulation of the needles using manual manipulation, electrical pulses, or heat. Its effects on pain are supported by numerous RCTs.

The strongest data for the analgesic effects of acupuncture comes from studies targeting pain in the absence of a serious illness. Systematic reviews and meta-analyses support its benefit in the management of joint pain (Collins et al., 2012), labour pain (Smith et al., 2011a), migraine (Linde et al., 2009a), tension headache (Linde et al., 2009b), dysmenorrhoeal (Smith et al., 2011b), and chronic pain in general (Vickers et al., 2012). For the treatment of cancer pain, a systematic review of 15 RCTs showed that acupuncture did not generate a better effect than drug therapy (risk ratio (RR), 1.12; 95% confidence interval (CI) 0.98– 1.28; p = 0.09); acupuncture plus drug therapy demonstrated a significant improvement when compared with drug therapy alone (RR, 1.36; 95% CI 1.13– 1.64; p = 0.003) (Choi et al., 2012).

One study of particular interest is an RCT in which auricular acupuncture demonstrated superiority over sham treatment in the control of cancer pain (Alimi et al., 2003). Many of the patients in that study had persistent neuropathic pain that had not responded to other treatments. In the management of chemotherapy-induced peripheral neuropathy, both a controlled pilot study and a case series using acupuncture showed some benefit, but with very small sample sizes (Wong and Sagar, 2006; Schroeder et al., 2012). Acupuncture’s effect on post-thoracotomy pain syndrome is mixed, with one study using embedded tiny needles showing no benefit (Deng et al., 2008) and another using electro-acupuncture demonstrating a reduction in opioid requirement (Wong et al., 2006).

The strongest support from clinical trials supports the efficacy of acupuncture for nausea and vomiting. A high-quality Cochrane systematic review of 11 trials (N = 1247) concluded that electro acupuncture has demonstrated benefit for chemotherapy-induced acute vomiting (Ezzo et al., 2006). In non-chemotherapy settings, another systematic review of more than 40 RCTs supports the effect of acupuncture in preventing or attenuating nausea and vomiting (Streitberger et al., 2006). Because the use of opioid analgesics may be associated with nausea and vomiting, acupuncture may be considered among approaches to address a common opioid toxicity.

In summary, the analgesic effect of acupuncture is supported by preclinical and clinical studies. Although its analgesic effects are better established in musculoskeletal pain and headache, and less well established for chronic pain due to cancer or other medical illnesses, the relative safety of acupuncture suggests that it should be considered in populations receiving palliative care—for both pain and nausea. Acupuncture is not associated with common opioid side effects, such as sedation, constipation, and nausea, and combining the use of both modalities appears warranted in order to manage pain in patients who do not respond favourably to opioids alone.

Massage therapy involves applying pressure to muscle and connective tissue with the intent to reduce tension and pain, improve circulation, and encourage relaxation. Massage techniques most commonly used in oncology include Swedish massage, aromatherapy massage, reflexology, and acupressure. All involve manual manipulation of soft tissues of the body by a trained therapist. However, the methods of applying touch, degree of educational preparation, regulatory requirements, and underlying theoretical frameworks vary widely among these modalities.

Clinical studies show that massage therapy can reduce anxiety, depression, and pain in cancer patients. A 2009 systematic review of massage therapy for cancer palliation and supportive care examined 14 RCTs, which studied anxiety (seven RCTs; N = 514), depression (three RCTs; N = 107), or pain (six RCTs; N = 718) (Ernst, 2009). It concluded that massage can alleviate a wide range of symptoms: pain, nausea, anxiety, depression, anger, stress, and fatigue. However, poor methodology among the studies makes the benefits encouraging but not compelling.

An earlier systematic review focusing on cancer patients included 12 RCTs, which also used anxiety (five RCTs; N = 236), depression (two RCTs; N = 63), and pain (three RCTs; N = 144) as end points (Wilkinson et al., 2008). The trials used standard care, attention, or low-intensity bodywork as control interventions. The reviewers concluded the data support massage therapy as an effective adjunct in cancer supportive care to reduce anxiety, depression, and pain, with stronger evidence for its effect on anxiety than depression or pain. However, the methodological quality of most included trials was poor.

Among non-randomized trials, results from an observational study (N = 1290) showed that massage improved pain scores for both inpatients and outpatients by 40%, and reduced other cancer-related symptoms by approximately 50% (Cassileth and Vickers, 2004). More recently, a pilot study comparing reflexology and Swedish massage therapy for cancer survivors aged 75 or older in nursing homes found that both interventions resulted in significant declines in salivary cortisol and pain, as well as improvements in mood. Further, both interventions were well tolerated in an elderly population of cancer survivors typically excluded from trials (Hodgson and Lafferty, 2012). Another randomized pilot study found that a combination of massage and other physiotherapy can reduce pain and improve mood in patients with terminal cancer (Lopez-Sendin et al., 2012).

In palliative care, precautions must be paid to the safety of massage therapy, as some patients may have a large tumour burden or bone metastases, and could be at risk for an exacerbation of pain, fracture, bruising, or bleeding. Strong pressure should not to be applied over areas of disease involvement. In these cases, gentle light touch massage or reflexology (hand or foot massage) can still be used.

In summary, evidence supporting the use of complementary therapies in pain management is encouraging but not definitive. In considering various treatment options for clinical practice, the strength of the evidence in favour of efficacy must be weighed against the risks and burdens to patients, and the potential alternatives or the lack thereof. From this perspective, the mind–body therapies, acupuncture, and massage therapy have a favourable record. They may improve symptoms, and the medical risk and burden they pose usually is negligible. They also encourage patient self-care and empowerment, making patients active participants in their care.

The use of complementary approaches may present financial concerns, as most of the time they are not covered by health insurance, but coverage for these therapies is expanding and reflects consumer demand along with managed care efforts to control costs. Financial barriers also may be partially overcome. Patients can be taught to practice mind–body interventions themselves, and yoga/qigong or meditation classes can be given to groups. Acupuncture also can be given in a group setting to lower unit costs, or patients can be taught to do acupressure (application of pressure, usually with a finger, on acupuncture points). Family members or caregivers can be taught to safely give massages.

The origin of pain, and the factors complicating it, should be considered when selecting from among the complementary modalities for pain. If the pain is augmented by anxiety, fear, depression, or sleep disturbance, or if the pain exacerbates psychological distress, mind–body therapies and massage therapy should be considered. If opioid therapy creates undesirable effects, such as sedation, constipation, fatigue, nausea, and emesis, the addition of acupuncture has the potential of lowering the required dose of pain medications.

Each patient’s belief system and cultural background should be taken into consideration. Patients who have a strong spiritual need, who wish a more naturalistic approach to health, and patients who have experienced benefit from these therapies previously, are more open to complementary therapies and appreciate their availability as an integrated component of mainstream care. Only by considering what is truly important to a patient as an individual can we provide optimal patient-centred palliative care, improve the quality of pain management, and comfort the patient to the best of our ability.