Knowledge and attitudes towards medicinal cannabis and complementary and integrative medicine (CIM): a survey of healthcare professionals working in a cancer hospital in Australia

Awareness of complementary and integrative medicine (CIM) and the prescription of medicinal cannabis (MC) amongst healthcare professionals (HCPs) is important for safe and effective clinical care of people affected by cancer. An average of 56% of Australians with cancer use CIM, including medicinal cannabis and traditional indigenous and complementary medicines [1, 2]. People with cancer want their cancer care team to be able to discuss CIM and MC; addressing these needs increases satisfaction, confidence and trust in treatment and engagement in their cancer treatment [3‐6]. HCPs can be credible sources to provide accurate and trusted information, and their beliefs or biases play an important role in patients’ decisions to share their CIM usage [7‐9]. However, recent research reveals that most nurses and oncologists have insufficient knowledge about CIM, leading to variable responses such as discouraging use, or being supportive but without adequate knowledge to refer or prescribe [1, 10]. Little is known about the attitudes of cancer care professionals to different types of CIM therapies or MC.

Medicinal cannabis has been available by medical prescription through a special access or authorised prescriber program in Australia since 2016, with many people with cancer reporting improvement in a range of physical and psychological symptoms [11]. Prescription of MC in Australia is only through medical practitioners, although nurses, psychologists and other healthcare professionals may impact patient's access given their direct involvement in patient care. Whilst prescribing of MC is relatively new in Australia, traditionally consumers were accessing cannabis products without prescription. Reluctance to seek prescribed medicinal cannabis was due to cost, disinterest from the medical profession and stigma regarding cannabis use, with frustration around misinformation leading to non-disclosure [12, 13].

Knowledge and attitudes of health professionals working in cancer care in Australia towards CIM and MC have been examined in several discrete surveys to date. One survey included only pharmacists and their attitude to biologically based complementary therapies in people with cancer [14]. Another study included all healthcare professionals and their attitude only to MC use in cancer[15]. A more recent survey examined attitudes towards CIM as a single group of therapies amongst diverse healthcare professionals working in cancer care [16]. All surveys identified an interest in wanting to learn more about MC or CIM. However, none of these surveys included both CIM and MC, or investigated attitudes towards specific CIM therapies, such as acupuncture, massage, herbs and dietary supplements and exercise therapy. We hypothesised that attitudes and knowledge may differ across discrete CIM therapies.

Our study sought to investigate attitudes and practices of healthcare professionals to the use of different complementary therapies, exercise, nutrition and medicinal cannabis, to understand knowledge gaps, and identify which areas participants were interested in learning about further. We were also interested in whether healthcare occupation influenced attitudes to CIM and MC, referral pathways for advice on CIM and interest in a pharmacy service to evaluate potential interaction between herbs and supplements with cancer treatments. The study was conducted at a hospital that provides a range of CIM as part of a comprehensive integrative oncology service alongside conventional cancer care. To improve service delivery and integration within the hospital, we also investigated the awareness of HCPs of the CIM offerings within the hospital setting.

This cross-sectional survey investigated attitudes and practices of healthcare professionals, working at a large cancer hospital in Australia, towards complementary and integrative medicine (CIM), exercise and lifestyle medicine and medicinal cannabis (MC). The study received ethics approval from the Sydney Local Area Health District Ethics Committee in May 2019 (HREC/18/RPAH/519). Results are reported according to the STROBE guidelines [17].

Of the 488 eligible healthcare professionals working within the hospital, 116 responded to the survey and provided demographic data (Table 1). The majority of participants were female (76%) and in the 31–50 year old age group (48%).

Healthcare professional participants included 53 nurses, 16 oncologists (including radiation and medical oncology), 11 pharmacists, 20 allied health professionals (including dietitians, exercise physiologists, physiotherapists and psychologists) and 16 other healthcare professionals (including surgeons, palliative and supportive care staff). Participants worked primarily in the hospital’s inpatient wards (31%) and the day therapy (chemotherapy) suites (18%), radiation oncology and outpatient clinics.

Our study found that nearly all 116 respondents supported the integration of complementary and integrative medicine (CIM) into cancer care, and believed these therapies can be beneficial to patients with cancer, but the majority of respondents did not feel they had adequate knowledge to advise patients on CIM. For medicinal cannabis (MC), attitudes were more ambiguous, with only half of respondents agreeing that there was adequate evidence for the efficacy of MC, or that MC was beneficial to people with cancer. Nearly all respondents wanted to learn more about complementary therapies; this is consistent with other studies [25]. Only 33% of healthcare professionals felt prepared to integrate CIM into their work. As hypothesised, HCPs knowledge of individual CIM therapies varied between mind-body, and herbs and supplements.

The majority of respondents agreed CIM has beneficial effects for people with cancer. Nearly all respondents believed CIM was beneficial to people with cancer, and mind-body therapies had beneficial effects on psychological symptoms such as depression and anxiety and stress management. MC may benefit cancer-related symptoms, and this was higher for symptoms such as managing cancer and treatment-related nausea and appetite. Side effects of MC were thought to be primarily driving impairment and drowsiness but there was uncertainty around other impacts.

With only a few exceptions, knowledge and attitudes to CIM and MC in our study were not influenced by age, gender, occupation or length of time at the hospital. Those respondents who had worked at the hospital longer and were older were more likely to report confidence in discussing CIM with patients and reported having sufficient knowledge about mind-body practices and herbs and supplements.

Knowledge gaps were highest for MC, with only 10% reporting they had adequate knowledge to recommend or 17% were familiar with the endocannabinoid system. Only 20% of HCPs were confident advising on the benefits and contraindications of herbs and supplements; confidence was slightly higher for mind-body practices (36%). All HCPs wanted to learn more about the benefits of CIM and MC. Interest was highest for dietary supplements (81%) and herbs (81%), with the majority of oncologists wanting to learn about the benefits and contraindications of dietary supplements and herbs.

Despite limited confidence in benefits and contraindications of herbs and supplements, only 7–14% of the HCPs would advise against the use of herbs and dietary supplements. In a pooled prevalence of studies of people with cancer, 22% used herbal medicine, and this is higher in certain population groups such as women with breast cancer where 41% reported use of herbal medicine [26, 27]. Dietary supplement use is higher, with studies indicating use by almost one in two people with cancer (including those receiving cancer treatment), with a slightly lower but significant (36%) level of consumption in men [28‐30]. Despite this prevalence of use in Australian cancer patients, respondents in our study did not feel they were equipped to advise on herbs and supplements, and this area received the highest interest by HCPs in learning more, compared to mind-body therapies.

Advice regarding the safe use of herbal medicine or dietary supplement use during cancer treatment is an important part of comprehensive cancer care. Yet only 16 cancer services in Australia have dedicated healthcare practitioners providing advice on the use of any CIM [31]. In our study, there was strong support for a pharmacy service to advise on the potential interaction and safety of herbs and/or supplements with cancer treatments. The majority of respondents stated this would make them more likely to recommend or allow use. More than half of the pharmacists in our survey reported that they were confident in advising on herbs and supplements. For CIM in general, respondents in our study were most likely to refer patients to the integrative and supportive care specialist within the hospital. Taken together, these findings indicate that the safety and choices of people with cancer and their supportive care can be greatly enhanced by providing a level of CIM and MC specialist knowledge within a comprehensive cancer setting.

Meeting cancer patient expectations, cultural preferences, beliefs and information needs improves patient outcomes [32]. One in two Australians with cancer uses CIM; it aligns with their personal values, beliefs and cultural identity [33]. People use CIM to help cope with the side effects of conventional cancer treatments, improve survival and long-term outcomes and support their mental health, wellbeing, weight management, self-efficacy and quality of life throughout the cancer continuum [7, 34‐36]. Additionally, patients receiving treatment at an institution that supports an IO program may have improved survival [33, 36‐38]. Our survey, in line with other studies, shows that the education, integration, pathways and translation of evidence into practice are major barriers to preferences being expressed by HCPs and people with cancer[16].

The establishment of designated cancer treatment centres in Australia with links to rural and remote centres may provide the basis for speciality advice on integrative oncology to patients and practitioners. Similar to the program of the National Cancer Institute designated cancer centres in the US have developed or are developing integrative oncology programs to assist, along with guidelines to support providers who participate in these programs [39, 40]. This would require the training of healthcare professionals in integrative oncology; competencies and training options are emerging [41, 42].

Whilst knowledge and attitudes of general practitioners to MC have been assessed [43], no studies conducted in Australia have explored attitudes of oncology HCPs. The findings in our study were similar to other studies conducted in Europe, where oncology healthcare professionals increasingly agree that MC reduces patient suffering and has benefits, particularly in people with advanced cancer [23].

The study was conducted at a hospital that has provided a range of CIM alongside conventional cancer care since it opened in 2013 and more recently prescription of MC. Through this exposure, we anticipated that the HCPs surveyed may have different knowledge and attitudes towards CIM compared to participants in other surveys. In other surveys 58–90% of HCPs reported having inadequate knowledge to answer questions about CIM, compared to 51% of HCPs in our study reporting that they felt confident in discussing CIM with patients[16]. However, this knowledge did not extend to side effects of MC or the endocannabinoid system, and most respondents did not have sufficient knowledge to make recommendations about MC use to people with cancer.

Our study had several limitations. We used convenience sampling from a single institution, and this may impact external validity. Participation in the survey was voluntary. However, the sample may not have been representative of the hospital population resulting in selection bias. The survey was administered in an anonymous and confidential manner which may mitigate some bias. There are no validated tools for measuring attitudes and beliefs to the use of cannabis in cancer care which may have resulted in information bias.

The uptake and integration of evidence-based and informed CIM and MC by oncologists and other HCPs in cancer care are hampered by a lack of knowledge of benefits and contraindications, gaps in education and training and the lack of adequate referral pathways [44]. The results of this survey will inform the development of ongoing education activities, knowledge sharing and research activities. Effective and safe integration of CIM and MC may require the targeted development of services such as pharmacy to evaluate the safety of herbs and supplements with a focus on drug-herb interactions and inclusion of cancer specialists who have received specific training in CIM and MC [45]. The targeted development of pharmacy and training of dedicated HCPs to provide advice on CIM and MC would support informing the choice of 1 in 2 Australians with cancer who use CIM.