ABSTRACT
Introduction
There are no prior studies investigating the perspectives of Opioid Treatment Program (OTP) clinicians on clients' cannabis use. This study examines the perspectives of OTP clinicians on patterns of cannabis use; harms and benefits; current and potential interventions and their confidence in implementing them.
Methods
Clinicians from six public OTP services in New South Wales completed the survey. Participants included nurses, doctors, pharmacists, allied health and consumer workers. Single‐level regression models were used to estimate participants' sex, role and experience effect.
Results
A total of 162 participants responded to the survey (estimated response rate 56%). Participants estimated 56.1% (±23.9) of OTP clients had used cannabis in the past month, and 44.9% (±6.5) had cannabis dependence. Clinicians indicated (15.3% ± 17.2%) clients identified problematic cannabis use and (10.7% ± 16.9) sought treatment in the past year. The harms most frequently identified by staff were cannabis dependence (46.5% ± 27.9%), financial issues (37.5% ± 29.2%) and increased tobacco use (33.1% ± 28.2%). The benefits most frequently identified were management of sleep problems (49.7% ± 27.8%), chronic pain symptoms (35.6% ± 24.3%) and improvements in mental health (48.3% ± 25.6%). Sixty‐five participants (63.7%) advocated for enhancing efforts to address cannabis use, with none supporting scaling down services. Clinicians prioritised withdrawal services (81%), harm reduction (77.4%), counselling (74%) and medicinal cannabis (59.8%), although the majority had low confidence in delivering most of these interventions.
Discussion and Conclusions
Despite awareness about cannabis use patterns and identification of both harms and benefits, clinicians identified low rates of cannabis interventions and low levels of confidence in delivering interventions.
Keywords: cannabis, clinicians, confidence, opioid dependence treatment, perspectives
Summary.
The survey including 162 Opioid Treatment Program (OTP) clinicians identified mixed attitudes of clinicians towards their OTP clients' cannabis use.
The most common harms identified were cannabis dependence, financial issues and increased tobacco use, and the most common benefits identified were management of sleep problems, improvement in mental health and management of chronic pain.
Clinicians identified only a minority of OTP clients (10.7%) sought treatment for their cannabis use in the last year. Self‐directed withdrawal, counselling and medicinal cannabis were reported to be the most sought interventions by OTP clients.
Clinicians believed types of interventions that need to be prioritised include withdrawal services, harm reduction interventions, counselling and medicinal cannabis. However, there were low levels of confidence in implementing most of these interventions in OTP services.
1. Introduction
Cannabis is the most frequently used illicit drug in Australia and across the world [1]. Cannabis use is associated with a range of physical, mental and social harms to individuals [2], including the development of cannabis dependence. Cannabis dependence is estimated to develop in 10%–20% of people with recent cannabis use [2] and between 20% and 50% of daily cannabis users [3]. The harms associated with cannabis use, including mental health (e.g., affective disorder, anxiety, psychosis, suicidal behaviour), dependence, physical (e.g., respiratory and cardiovascular disease) and social harms (e.g., motor vehicle accidents, school dropouts, unemployment) have been well documented [2].
However, there is now also increasing recognition that cannabis and/or cannabinoid extracts can be associated with a range of therapeutic benefits for clients in areas such as chronic pain, epilepsy, palliative care and clients receiving chemotherapy [4]. The Australian Government has legalised the use of medicinal cannabis since 2016 [5], classifying any medicinal cannabis containing more than 2% tetrahydrocannabinol (THC) as ‘controlled’ medicines (Schedule 8) [6] and products containing cannabidiol (CBD) (and less than 2% THC) as prescription only medication (Schedule 4) [7]. In Australia, the Therapeutic Goods Administration has established regulatory frameworks (Special Access and Authorised Prescriber schemes) enabling clients to be prescribed medicinal cannabis products legally [8]. Chronic pain, anxiety and sleep disorders are the most frequent indications [9, 10], despite limited and inconsistent evidence of efficacy for anxiety [11], sleep disorders [12] and chronic pain [13, 14]. There have also been changing community perspectives in recent years regarding cannabis use, with increasingly positive views regarding legalisation and reduced attribution of harms [15].
Cannabis legalisation in Australia has undergone reforms since 1987, transitioning from strict prohibition to the introduction of fines for minor cannabis‐related offences in some states and territories, the nationwide legalisation of medicinal cannabis in 2016 [16] and decriminalisation in one Australian state (South Australia) and two territories (Northern Territory and Australian Capital Territory) [17]. Currently, in New South Wales (NSW), where this study is conducted, use, supply and possession of cannabis are illegal with the exception of prescribed medicinal cannabis [16]. Cannabis is also the most widely used substance by Australian clients in Opioid Treatment Programs (OTP) [18]. Data from clients entering NSW Health public sector OTPs indicate 38.3% of clients used cannabis in the preceding month, with 20.4% of clients reporting regular use (> 3 days a week on average) [19]. The relationship between cannabis use and OTP outcomes is unclear [20, 21]. Some studies report an association between increased cannabis use and poorer treatment retention [22, 23] and more severe opioid withdrawal symptoms [24, 25]. However, the opposite has also been reported: that cannabis use increases treatment retention [26, 27], alleviates withdrawal symptoms [28] and suppresses opioid craving [24, 29]. Furthermore, other studies report no association between cannabis use and craving, withdrawal symptoms [30, 31, 32], opioid use [21, 30, 33, 34] and treatment adherence [28, 31, 35]. Such equivocal findings may contribute to indecision amongst OTP clinicians and services in whether or how they address cannabis use with their clients. In addition, changing community perceptions regarding cannabis use [36] may also impact upon how clients and clinicians in OTPs perceive and address cannabis use.
There are few effective therapeutic interventions for treating cannabis use disorder. Psychological therapies (e.g., cognitive behavioural therapy, motivational enhancement therapy) appear to assist 20%–30% of clients seeking treatment for cannabis dependence to reduce their long‐term cannabis use [37]. Withdrawal interventions can help alleviate symptoms; however, they do not appear to impact long‐term cannabis use in most clients [38]. While harm reduction approaches such as using ‘low‐potency’ cannabis products have been proposed [39], it remains unclear to what extent these interventions are provided to clients, nor their effectiveness in reducing harms [40]. Research has identified the potential of prescribed medicinal cannabis products such as nabiximols (equal parts of THC and CBD) and CBD [38] for the treatment of cannabis use disorder [41], these have not been systematically researched in clients with both cannabis and opioid use disorder.
Clinicians' perspectives about medicinal cannabis have been investigated widely in different settings. Systematic reviews demonstrated that clinicians' support for medical cannabis legalisation has increased through the years [42, 43] and the self‐perceived knowledge reported to be poor regardless of clinicians' field of practice [42, 43]. However, recent systematic reviews identified only one study investigating attitudes towards medicinal cannabis and clients' cannabis use in clinicians working in the addiction field. This American study recruited 1207 addiction clinicians with Associate, Bachelor, Masters or Doctoral degrees. The participants in this study demonstrated mixed attitudes towards medicinal cannabis and cannabis use. Most clinicians believed cannabis use is ‘trading one addiction for another’ and that cannabis does not alleviate cravings for other substances, however, some believed both cannabis and medicinal cannabis may potentially assist in managing conditions such as anxiety and insomnia in clients suffering from substance use disorder [44].
Despite the high prevalence of cannabis use in OTP clients, we identified no prior study investigating the perspectives of OTP clinicians about clients' illicit or medicinal cannabis use. A better understanding of OTP clinician perspectives is important in codesigning more attractive and effective interventions with consumers, and in better understanding their workforce development needs. This study aims to address this gap, examining the perspectives of staff working in specialist OTP settings regarding:
the prevalence of cannabis use, cannabis dependence, harms and benefits associated with cannabis use amongst their clients;
the extent to which clinicians address cannabis use with their clients, and the confidence of clinicians in implementing interventions to address cannabis use;
the range of services that clinicians believe should be available for OTP clients regarding cannabis use, including the role of medicinal cannabis.
2. Methods
2.1. Study Design and Setting
Data for this study were taken from a cross‐sectional online survey of clinicians working in specialist public sector OTP services in NSW, Australia. OTP services from six Local Health Districts (LHD) and Health Networks (HNs) across NSW agreed to participate in the project, as part of the NSW Drug and Alcohol Clinical Research and Improvement Network (DACRIN) [45]. The participating LHDs and HN catchment areas represent approximately 50% of the NSW population and included four metropolitan and 2 regional/rural districts. The project was coordinated by the lead author, with a multidisciplinary steering committee comprised of site investigators from each LHD, a consumer representative and a statistician. The study was approved by the Sydney Local Health District Human Research Ethics Committee (X22‐0327 and 2022/ETH01545).
2.2. Participants and Recruitment
Participants were clinicians employed in public outpatient specialist OTP services providing medication for opioid use disorder (such as methadone and buprenorphine formulations) only to outpatient clients and actively involved in providing medication for opioid use disorder to clients. The range of professional backgrounds included nurses, medical practitioners, allied health workers, pharmacists and consumer workers (see Table 1 for details of employment categories). Administration staff or those without direct client contact were ineligible to participate. Staff could be employed part‐ or full‐time, regardless of duration of employment.
TABLE 1.
Characteristics of clinicians.
| n (%), N = 162 | |
|---|---|
| Sex | |
| Female | 102 (63) |
| Male | 53 (32.7) |
| Prefer not to answer | 7 (4.3) |
| Age, years | |
| Mean (SD) | 45.3 (12.6) |
| Median (range; IQR) | 45 (20–73; 34–55) |
| Employment locations | |
| Site 1 | 53 (32.7) |
| Site 2 | 34 (21) |
| Site 3 | 27 (16.7) |
| Site 4 | 24 (14.8) |
| Site 5 | 13 (8) |
| Site 6 | 11 (6.8) |
| Roles | |
| Nurses a | 80 (49.4) |
| Doctors b | 36 (22.2) |
| Allied health c | 24 (14.8) |
| Others d | 22 (13.6) |
| Employment hours per week | |
| Part time: ≤ 20 | 54 (33.3) |
| Part time: 21–30 | 27 (16.7) |
| Fulltime: ≥ 31 | 81 (50) |
| OTP employment history, years | |
| Mean (SD) | 8.7 (8.8) |
| Median (range; IQR) | 5 (0–46; 2–14) |
Abbreviations: IQR, interquartile range; OTP, Opioid Treatment Program.
Enrolled nurses, registered nurses, midwives, clinical nurse specialists, clinical nurse consultants, nurse unit managers, nurse practitioners and clinical nurse educators.
Junior medical officers (registrars or residents), staff specialists, visiting medical officers and career medical officers.
Social workers, counsellors, psychologists.
Managers, pharmacists and consumer workers.
Eligible staff were notified of the study by email from their site investigator, with links to the Participant Information Statement, confirmation of eligibility, electronic informed consent and online survey. Participation was voluntary and anonymous (only details of the participant's profession, gender and age group were collected). The online survey was active for 6 weeks between March 2023 and April 2023, and site investigators sent regular email reminders to all eligible clinicians encouraging them to participate. The site investigator at each LHD/HN provided the number of eligible staff within their service to estimate participation rates.
2.3. Study Measures and Data Collection
The survey was developed by the lead author in consultation with the project steering committee. The survey's questions were developed according to the study's aims, deriving from previous studies on staff attitudes on drug and alcohol interventions or medicinal cannabis [42], and tailored for the study's purpose. The draft survey was piloted by OTP clinicians for face validity and refined accordingly. The term ‘cannabis’ used in the survey was defined as any form of cannabis used by clients (inclusive of any cannabinoid composition (e.g., THC or CBD content), formulation (e.g., flower, orals) or legal status (prescribed or illicit).
The survey contained 73 items in five sections: (i) participant details (socio‐demographic characteristics; 7 items); (ii) clinicians' perspectives on their clients' patterns of cannabis use (5 items, 7‐point Likert scale) (see Data S1, Section B Questions 2.1–2.5); (iii) levels of problematic cannabis use (4 items, 7‐point Likert scale) (see Data S1, Section B Questions 3.1–3.4); (iv) clinicians perspectives on the harms and benefits associated with their clients' cannabis use, asking clinicians' ideas about the percentage of their clients who used cannabis in the last months, experiencing various harms and benefits (27 items, 7‐point Likert scale) (see Data S1, Section B Questions 4.1–4.27); (v) clinicians' perspectives on strategies sought by clients (9 items), extension and location of services (5 and 2 items, respectively), interventions to be prioritised (9 items) and confidence in delivering therapeutic strategies (5 items 3‐point Likert scale) (see Data S1, Section C Questions 5–9.5). University of Sydney REDCap 13.4.10, a secure web platform for building and managing online surveys and databases, was used for data capture.
2.4. Statistical Analysis
Variables where the respondents were asked to estimate percentages of clients meeting some criteria were designed as categorical variables to allow for inaccuracies in estimates. Categories were ranges of estimated percentages (e.g., 0%, 1–20%, 21–40%, 41–60%, 61–80% and 81–100%). For reporting mean and standard deviation and ease of communicating the results [46], we converted these categorical variables to numerical variables by taking the mid‐point of the category selected (e.g., if 61%–80% was selected, it was assigned the number 70%). Missing data was not imputed. For regression modelling, dependent variables were (a) ordinal variables [e.g., percentage of total OTP clients used cannabis in the last month], (b) binary categorical variables (e.g., OTP services for addressing cannabis use amongst clients) and (c) bounded count variables (e.g., number of clinicians with various level of confidence in delivering interventions to address cannabis use). The independent variables in all these models were role (four‐level categorical: nurses [reference level] vs. doctors vs. allied health vs. other), sex (male [reference] vs. female) and years of experience (numeric, in years employed in OTP clinic: range [0–46]). As years of experience exhibited a significant correlation with age, verified by Pearson's test (correlation coefficient = 0.6, p < 0.001) and was more relevant to our study aims, years of experience was chosen. Single‐level regression models were used to analyse the data, with the form of the dependent variable determining the type of regression model: For ordinal and bounded count dependent variables we used ordinal regression and for binary categorical variables we used logistic regression. We considered coefficients to be significant if their 95% confidence intervals (CI) excluded 0 (for numeric dependent variables) or 1 (for binary categorical or count dependent variables). CIs were adjusted for multiple comparisons utilising the Scheffe method [47].
3. Results
3.1. Participation and Clinicians' Characteristics
Out of approximately 300 clinicians working in OTP services across the six LHDs/HNs, 162 participants provided consent to participate in the survey and responded to the survey questions (an estimated response rate of 54%).
The mean age of participants was 45.3 (±12.6) years and had worked for a mean of 8.7 (±8.8) years in OTP services. Most were female (n = 102, 63%), and half worked full‐time (n = 81, 50%) (Table 1).
3.2. Staff Perspectives on Patterns of Use, Problematic Use and Harms and Benefits Associated With Cannabis
3.2.1. Patterns of Use and Problematic Use
Participants estimated that 56.1% (±23.9) of their OTP clients reported cannabis use in the preceding month (Table 2), of whom 49.5% (±29.6) used cannabis between 4 and 7 days per week.
TABLE 2.
Clinicians' perspectives of pattern of cannabis use, problematic use, and harms and benefits.
| Nurses a , mean (SD) | Doctors b , mean (SD) | Allied health c , mean (SD) | Other d , mean (SD) | Total, mean (SD) | |
|---|---|---|---|---|---|
| Pattern of cannabis use | |||||
| Percentage of total OTP clients used cannabis in the last month | 59.1 (25.9) | 54.2 (20.5) | 59.0 (22.9) | 45.3 (22.9) | 56.1 (23.9) |
| Frequency of last month cannabis use among clients who used cannabis: | |||||
| Less than 1 day per week | 15.9 (20.0) | 16.5 (17.1) | 16.5 (22.3) | 12.6 (12.9) | 15.8 (18.9) |
| 1–3 days per week | 34.6 (24.7) | 36.4 (18.9) | 30.3 (29.0) | 38.6 (21.5) | 34.8 (23.7) |
| 4–7 days per week | 49.6 (30.5) | 47.1 (24.4) | 53.2 (31.5) | 48.8 (35.8) | 49.5 (29.6) |
| Percentage of last month cannabis use clients that: | |||||
| Clinicians identified them with problematic cannabis | 42.4 (27.9) | 42.7 (25.4) | 36.1 (28.8) | 34.4 (26.0) | 40.9 (26.8) |
| Self‐identified cannabis use as a problem | 14.1 (16.6) | 14.7 (11.0) | 23.8 (30.2) | 11.1 (7.8) | 15.3 (17.2) |
| Included addressing cannabis use in most recent global care plan | 15.3 (18.4) | 10.0 (8.2) | 19.2 (32.5) | 6.7 (5.2) | 13.7 (18.4) |
| Percentage of total OTP clients with cannabis dependency | 51.6 (28.1) | 36.2 (19.9) | 42.5 (28.4) | 41.9 (26.1) | 44.9 (6.5) |
| Percentage of total OTP clients that sought cannabis treatment in the last year | 8.7 (13.9) | 8.6 (3.6) | 24.6 (34.8) | 7.1 (4.9) | 10.7 (16.9) |
| Harms associated with cannabis use | |||||
| Cannabis dependence or addiction | 51.6 (30.5) | 40.7 (23.0) | 51.5 (26.4) | 37.7 (28.6) | 46.5 (27.9) |
| Cannabis withdrawal | 26.8 (29.1) | 26.2 (20.9) | 31.7 (32.1) | 28.2 (30.9) | 27.4 (27.0) |
| Impaired memory | 24.0 (27.3) | 22.5 (19.1) | 35.8 (27.1) | 26.0 (20.1) | 25.7 (24.6) |
| Cognitive problems other than impaired memory | 20.3 (25.1) | 21.5 (19.3) | 24.5 (23.4) | 30.0 (20.5) | 22.5 (22.7) |
| Increasing tobacco use | 27.2 (28.1) | 39.0 (25.8) | 36.1 (32.8) | 35.4 (29.1) | 33.1 (28.2) |
| Increasing other drugs use | 14.1 (19.7) | 18.1 (21.9) | 16.7 (19.2) | 11.0 (16.6) | 15.4 (19.8) |
| Relationship problems | 19.7 (24.3) | 22.0 (17.8) | 31.7 (28.5) | 14.5 (12.9) | 21.5 (22.1) |
| Work or study problems | 21.9 (29.8) | 19.6 (15.2) | 27.5 (28.0) | 24.5 (30.4) | 22.4 (25.0) |
| Financial problems | 35.6 (29.7) | 37.3 (27.6) | 44.6 (28.5) | 36.4 (34.4) | 37.5 (29.2) |
| Parenting or other carer problems | 20.9 (25.7) | 18.3 (14.7) | 23.6 (30.1) | 22.7 (32.0) | 20.7 (24.3) |
| Cannabis related legal problems | 23.1 (25.8) | 17.8 (15.4) | 31.5 (28.5) | 17.3 (21.9) | 22.2 (23.5) |
| Impaired driving | 22.5 (26.2) | 17.1 (21.2) | 14.6 (19.0) | 17.5 (27.1) | 19.2 (23.7) |
| Increased stress, anxiety, or depression | 24.3 (28.1) | 30.0 (22.3) | 38.5 (33.1) | 16.0 (24.1) | 27.2 (27.1) |
| Increased features of psychosis | 13.2 (19.8) | 11.1 (12.6) | 16.7 (20.6) | 11.1 (15.4) | 12.8 (17.3) |
| Increase suicidal ideation and/or attempt | 7.0 (14.0) | 8.8 (14.2) | 13.9 (18.0) | 7.8 (13.0) | 8.6 (14.5) |
| Sleep problems | 24.3 (31.1) | 25.8 (22.1) | 50.8 (31.5) | 13.3 (16.6) | 27.3 (28.9) |
| Respiratory problems | 17.6 (24.2) | 22.6 (16.0) | 17.5 (23.0) | 20.0 (22.8) | 19.3 (21.6) |
| Cardiac problems | 8.0 (13.9) | 11.0 (12.1) | 9.0 (21.8) | 5.5 (10.1) | 8.6 (14.2) |
| Cannabis hyperemesis syndrome | 7.1 (15.2) | 7.5 (10.7) | 5.8 (14.4) | 4.4 (10.1) | 6.8 (13.2) |
| Benefits associated with cannabis use | |||||
| Control/limiting use of other drugs | 28.5 (19.7) | 20.3 (17.7) | 37.7 (28.6) | 25.8 (24.3) | 27.0 (21.5) |
| Control/limiting opiate withdrawal symptoms | 22.7 (22.9) | 14.9 (16.0) | 20.7 (23.1) | 19.3 (22.0) | 19.7 (21.0) |
| Stabilising dose of OTP | 22.2 (24.3) | 18.6 (23.2) | 27.7 (30.0) | 16.7 (18.8) | 21.2 (24.1) |
| Enhancing the subjective effects of OTP | 21.8 (23.1) | 15.8 (20.4) | 25.0 (25.0) | 12.0 (13.2) | 19.3 (21.7) |
| Enhancing the subjective effects of other drugs | 21.5 (19.7) | 17.4 (18.5) | 24.1 (21.5) | 15.4 (12.1) | 19.9 (18.7) |
| Managing chronic pain symptoms | 34.9 (25.3) | 32.2 (21.5) | 41.3 (23.6) | 39.3 (27.9) | 35.6 (24.3) |
| Managing mental health problems | 49.0 (27.1) | 44.2 (22.6) | 58.0 (23.7) | 44.2 (28.4) | 48.3 (25.6) |
| Managing sleep problems | 50.8 (29.3) | 44.7 (25.1) | 56.7 (26.9) | 49.2 (29.6) | 49.7 (27.8) |
Note: Bolded values indicate significant difference from the reference category (nurses).
Abbreviation: OTP, Opioid Treatment Program.
Enrolled nurses, registered nurses, midwives, clinical nurse specialists, clinical nurse consultants, nurse unit managers, nurse practitioners and clinical nurse educators.
Junior medical officers (registrars or residents), staff specialists, visiting medical officers and career medical officers.
Social workers, counsellors and psychologists.
Managers, pharmacists and consumer workers.
Participants estimated that 44.9% (±6.5) of their OTP clients met criteria for cannabis dependence and estimated past‐month problematic cannabis use in 40.9% (±26.8) of clients. However, clinicians indicated that a much lower proportion of clients (15.3% ± 17.2) had recently identified cannabis use as an issue or problem to address during treatment planning consultations, and even fewer clients (10.7% ± 16.9) had sought treatment for their cannabis use within the past year. In adjusted regression models, there were no statistically significant differences in all the aforementioned estimates based on sex, different professions or years of experience, with the exception that female clinicians (n = 55) estimated more past‐month problematic cannabis use in their clients compared with males (n = 38) (adjusted Coefficient [aCoeff] 1.1, CI 0.2, 1.9), adjusted for sex, years of experience and multiple comparisons (Table 2).
3.2.2. Harms and Benefits
The harms and benefits of cannabis use were examined based on clinicians' perceptions of the percentage of their clients who experienced either benefits or harms from cannabis use over the past month (see Data S1, Section B Questions 4.1–4.27).
The most frequently occurring cannabis‐related harms clinicians identified in their clients were cannabis dependence (46.5% ± 27.9), financial issues (37.5% ± 29.2) and increased tobacco use (33.1% ± 28.2), with no significant differences based on sex, professions or levels of experience. Female clinicians reported a higher percentage of clients with impaired memory due to cannabis use compared to male clinicians (aCoeff 1.1, CI 0.1, 2.2). Allied health clinicians estimated more clients suffering from sleep problems compared to nurses (aCoeff 1.87, CI 0.02, 3.72) adjusted for sex, years of experience and multiple comparisons. Each additional year of employment in drug and alcohol services was associated with a lower estimated percentage of clients experiencing problems related to work or study (aCoeff −0.04, CI −0.08, −0.01) adjusted for sex and different professions (Table 2).
The cannabis‐related benefits most frequently identified by staff in their clients were the management of sleep problems (49.7% ± 27.8), improvements in mental health (48.3% ± 25.6) and management of chronic pain symptoms (35.6% ± 24.3), with no significant differences across sex, professions and level of experience for all mentioned estimates. Female clinicians reported a lower percentage of their clients benefiting from cannabis use for controlling or limiting use of other drugs in comparison to male clinicians (aCoeff −0.95, CI −1.87, −0.03) adjusted for profession and years of experience (Table 2).
3.3. Clinicians' Perspectives and Confidence in Delivering Interventions for Addressing Cannabis Use
3.3.1. Interventions
Self‐directed withdrawal (without professional or organised ‘self‐help’ support) was selected as the most sought intervention by 39.8% of clinicians (n = 41) followed by counselling alone (n = 20, 19.4%), medicinal cannabis (n = 14, 13.6%), withdrawal and counselling (n = 11, 10.7%), other medications (e.g., antidepressants, antipsychotics) (n = 6, 5.4%), inpatient withdrawal only (n = 4, 3.8%), outpatient withdrawal only (n = 3, 2.9%), self‐help groups (e.g., Marijuana Anonymous and Smart Recovery) (n = 3, 2.9%) and residential rehabilitation (n = 1, 0.9%). There was no significant difference in selected interventions based on sex, profession or years of experience.
Sixty‐five participants (63.7%) advocated for enhancing efforts to address cannabis use in OTP clients, 19 (18.6%) indicated responses should be ‘client‐led’, and none supported scaling down services. Most clinicians (n = 79, 77.4%) recommended integrating cannabis treatment interventions into OTP services rather than referring clients to external services. Amongst the proposed interventions, withdrawal services (inpatient and outpatient; n = 83, 81%), harm reduction interventions (n = 79, 77.4%), counselling (n = 75, 74%), medicinal cannabis (n = 61, 59.8%) and self‐help programs (n = 52, 51%) were identified as the interventions that should be prioritised (Table 3).
TABLE 3.
Clinicians perspectives of interventions and confidence in delivering interventions for addressing cannabis use.
| Nurses a , N (%) | Doctors b , N (%) | Allied health c , N (%) | Other d , N (%) | Total, N (%) | |
|---|---|---|---|---|---|
| Extension of services for addressing cannabis use | |||||
| We should do more to address cannabis use | 29 (63.0) | 22 (73.3) | 6 (42.9) | 8 (66.7) | 65 (63.7) |
| We should do less to address cannabis use | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Current approach is ‘about right’ | 5 (10.9) | 4 (13.3) | 3 (21.4) | 1 (8.3) | 13 (12.7) |
| Should be client‐led | 9 (19.6) | 2 (6.7) | 5 (35.7) | 3 (25.0) | 19 (18.6) |
| Don't know | 3 (6.5) | 2 (6.7) | 0 (0.0) | 0 (0.0) | 5 (4.9) |
| Location for cannabis intervention | |||||
| Delivered within the OTP service | 27 (58.7) | 28 (93.3) | 13 (92.9) | 11 (91.7) | 79 (77.4) |
| Referred to external services | 19 (41.3) | 2 (6.7) | 1 (7.1) | 1 (8.3) | 23 (22.5) |
| Services needed to be prioritised | |||||
| Harm reduction interventions | 34 (73.9) | 24 (80.0) | 11 (78.6) | 10 (83.3) | 79 (77.4) |
| Counselling | 33 (71.7) | 23 (76.7) | 10 (71.43) | 9 (75.0) | 75 (73.5) |
| Inpatient withdrawal | 13 (28.3) | 5 (16.7) | 3 (21.4) | 8 (66.7) | 29 (28.4) |
| Outpatient withdrawal | 20 (43.5) | 14 (46.7) | 9 (64.3) | 11 (91.7) | 54 (52.9) |
| Residential rehabilitation | 12 (26.1) | 5 (16.7) | 2 (14.3) | 5 (41.7) | 24 (23.5) |
| Self‐help programs | 26 (56.5) | 11 (36.7) | 8 (57.1) | 7 (58.3) | 52 (51.0) |
| Medicinal cannabis | 26 (56.5) | 16 (53.3) | 10 (71.4) | 10 (71.4) | 61 (59.8) |
| Other medications | 11 (23.9) | 7 (23.3) | 4 (28.6) | 5 (41.7) | 27 (26.5) |
| Other | 3 (6.5) | 1 (3.3) | 0 (0.0) | 1 (8.3) | 5 (4.9) |
| Confidence in implementing strategies | |||||
| Harm reduction advice | |||||
| Very confident | 21 (45.6) | 17 (56.7) | 9 (64.3) | 5 (41.7) | 52 (51.0) |
| Somewhat confident | 19 (41.3) | 13 (43.3) | 5 (35.7) | 5 (41.7) | 42 (41.2) |
| Not very confident | 6 (13.1) | 0 (0.0) | 0 (0.0) | 2 (16.6) | 8 (7.8) |
| Counselling | |||||
| Very confident | 6 (13.0) | 7 (23.3) | 12 (85.7) | 11 (20.4) | 27 (26.5) |
| Somewhat confident | 25 (54.3) | 19 (63.3) | 2 (14.3) | 30 (55.6) | 53 (52.0) |
| Not very confident | 15 (32.7) | 4 (13.4) | 0 (0.0) | 13 (24.0) | 22 (21.6) |
| Outpatient withdrawal | |||||
| Very confident | 7 (15.2) | 14 (46.7) | 2 (14.3) | 4 (33.3) | 27 (26.5) |
| Somewhat confident | 19 (14.3) | 11 (36.7) | 7 (50.0) | 4 (33.3) | 41 (40.2) |
| Not very confident | 20 (43.5) | 5 (16.6) | 5 (35.7) | 4 (33.3) | 34 (33.3) |
| Inpatient withdrawal | |||||
| Very confident | 1 (7.1) | 29 (28.4) | 3 (25.0) | 13 (24.1) | 29 (28.4) |
| Somewhat confident | 6 (42.9) | 24 (23.5) | 3 (25.0) | 14 (25.9) | 24 (23.5) |
| Not very confident | 7 (50.0) | 49 (48.1) | 6 (50.0) | 27 (50.0) | 49 (48.0) |
| Medicinal cannabis treatment | |||||
| Very confident | 3 (6.5) | 2 (6.7) | 0 (0.0) | 1 (8.3) | 6 (5.9) |
| Somewhat confident | 9 (19.6) | 9 (30.0) | 6 (42.9) | 2 (16.7) | 26 (25.5) |
| Not very confident | 34 (73.9) | 19 (63.3) | 8 (57.1) | 9 (75.0) | 70 (68.6) |
Note: Bolded values indicate significant difference from the reference category (nurses).
Abbreviation: OTP, Opioid Treatment Program.
Enrolled nurses, registered nurses, midwives, clinical nurse specialists, clinical nurse consultants, nurse unit managers, nurse practitioners and clinical nurse educators.
Junior medical officers (registrars or residents), staff specialists, visiting medical officers and career medical officers.
Social workers, counsellors and psychologists.
Managers, pharmacists and consumer workers.
Confidence in delivering interventions: The only intervention which the majority of clinicians reported feeling ‘very confident’ in delivering, was harm reduction advice (Table 3). Approximately half of the clinicians reported feel ‘somewhat confident’ in delivering outpatient withdrawal or counselling services, however there were low levels of confidence in delivering inpatient withdrawal or medicinal cannabis, with 6% reporting being ‘very confident’ in delivering medicinal cannabis treatment.
Female clinicians (n = 58) were less confident than male clinicians (n = 40) in providing both outpatient (adjusted odds ratio [aOR] 0.3, CI 0.2–0.9) and inpatient withdrawal management (aOR 0.3, CI 0.1–0.8), after adjusting for years of experience and profession. Allied health professionals (n = 14) were much more confident in providing counselling services to clients than nurses (n = 46; aOR 38.8; CI 3.5, 433.1) adjusted for sex, years of experience and multiple comparisons (Table 3). Every year of employment in drug and alcohol services was associated with an 8% increase in confidence in implementing outpatient withdrawal treatment (aOR 1.08; CI 1.03, 1.13) and a 4% increase in confidence in providing inpatient withdrawal treatment (aOR 1.0; CI 1.02, 1.08) adjusted for sex and profession.
4. Discussion
Results from this survey highlight some of the paradoxes clinicians face when addressing cannabis use amongst OTP clients. Consistent with results from the one previous study conducted amongst addiction clinicians [44], clinicians in this study demonstrated mixed attitudes towards cannabis use in their OTP clients. Clinicians identified high rates of cannabis dependence in their clients, which was selected as the most common ‘harm’ associated with use of cannabis. However, clinicians reported cannabis to also be associated with a range of benefits such as management of mental health, pain and sleep problems, highlighting that many clinicians have mixed perspectives regarding cannabis use in this client population. Clinicians mostly indicated that they should enhance their response to their OTP clients' cannabis use, as only a minority of clients had attempted any intervention for cannabis use or identified cannabis use as an issue to be addressed in treatment. There were low levels of confidence in delivering most types of interventions addressing cannabis use, particularly medicinal cannabis.
Clinicians estimated high rates of cannabis use in this client population—estimating over half (56.1%) had used cannabis in the past month, and about half of those using cannabis most days (4–7 days) per week. This is a higher estimate than recent data of 3158 clients entering NSW public sector treatment with opioids as the primary drug of concern—in which past month cannabis use was reported by 34.5% of clients [48], although the frequency of cannabis use was comparable (with approximately half of clients reporting using 4–7 days per week on average) across the two studies. It is unclear as to why staff reported a higher proportion of their clients with recent cannabis use. Staff estimated almost half (44%) of all their OTP clients met criteria for (past year) cannabis dependence, and that over 40% had experienced cannabis‐related problems within the past month. It is also unclear the extent to which OTP clients ‘self‐medicate’ with cannabis use [49], which may be partially explaining the low level of cannabis treatment seeking in OTP clients. We aim to compare staff estimates with data from clients from OTP services in future research.
Clinicians identified cannabis use to be associated with a range of benefits and harms in their OTP clients and to our knowledge, this is the first survey where addiction clinicians were asked about possible benefits of cannabis use. Consistent with previous reports [2, 50, 51], a range of social, psychological and physical harms were identified, with dependence, financial problems, increased tobacco use and cognitive problems the most commonly reported. Also, many clinicians reported cannabis helped their OTP clients manage sleep, mental health and chronic pain symptoms. While pain, mood and sleep disorders are very common comorbidities in the OTP population [52, 53], there have been no trials of medicinal cannabis use in the OTP population to manage these conditions, and as such it is not possible to comment with confidence as to whether cannabis use is indeed beneficial or harmful for these conditions in OTP clients. However, these reported benefits are consistent with many general cannabis users reports of effectiveness across many cross‐sectional and observational studies [9, 10]. Evidence from well‐controlled clinical trials regarding the role of medicinal cannabis in the treatment of depression, anxiety, or sleep is less certain (where high‐quality studies are largely lacking [12]). In addition, the evidence for the management of most pain conditions is also only modest [54]. The discrepancy between positive consumer and social media reports, equivocal findings from randomised trials and long‐reported evidence of cannabis‐related harms may contribute to confusion or uncertainty for clinicians and consumers in understanding the impact of cannabis upon mood, sleep and pain. In this study, benefits such as alleviating opioid withdrawal symptoms, and stabilising OTP dose were reported in less than 20% of OTP clients. The evidence for cannabis fulfilling these functions is also mixed [24, 25], and it is unclear whether the low proportions reported by clinicians again represent clients' reported experiences or based on their observation and experience. Clinicians expressed diverse responses on the harms and benefits of cannabis use. For example, clinicians indicated that 15% of clients who use cannabis experience increased use of other substances, while 27% clients use cannabis to control or limit their use of other drugs. These findings highlight the differing perspectives amongst clinicians regarding the impact of cannabis on OTP clients. Cannabis, like other substances, can lead to varying harms or benefits depending on the individual user, patterns of use or the social context in which it is consumed [39, 55, 56]. For many years, cannabis was primarily regarded as a harmful substance due to prohibition in Australia and around the world [57] and research studies historically focused only on harms [57]. In recent years, clinicians' beliefs surrounding the effects of cannabis on their clients are changing [42], in response to relaxation of prohibition [58], a growing body of evidence indicating medical benefits [9, 59], and increased public support [36] and media campaigns [60, 61]. Our study revealed mixed perspectives amongst addiction clinicians regarding the harms and benefits of cannabis use in OTP clients. This may be attributed to the potential of cannabis to have both harmful and beneficial effects, depending on the type of user [55]. These diverse perspectives also may reflect clinicians' beliefs shaped by their training, their personal experiences or being influenced by broader community attitudes towards cannabis use. It is crucial to distinguish between clinicians' perspectives and the actual harms and benefits reported by clients from their cannabis use. Hence, our group is currently undertaking further research examining OTP clients' perspectives on cannabis use, comorbidities and potential associated harms and benefits, which may better address these questions.
While clinicians estimated 41% of their clients had harmful cannabis use (past month), they reported only 15% of their clients had self‐identified as having problematic cannabis use. There could be a few reasons for this gap: (a) many clients do not consider their cannabis use to be problematic, or consider the benefits to outweigh any harms [9] (consistent with a self‐medication hypothesis), (b) clinicians may be overestimating problematic cannabis use in their clients, potentially due to a focus on the harms of cannabis in their daily clinical practice and a tendency to emphasise harmful use, influenced by the nature of their profession (institutional effect), (c) clients are aware they have problematic cannabis use but are reluctant to express this to their clinician, either because they consider clinicians have little to offer in the way of treatment [51], or due to concerns regarding negative consequences upon their treatment (e.g., loss of take‐away doses, increased monitoring) or the stigma of being identified as an active substance user [50]. These explanations are not mutually exclusive.
More than 60% of OTP clinicians endorsed being more proactive in addressing cannabis use in OTP clients, with more than 70% suggesting integrating interventions for addressing cannabis dependency in OTP settings. The interventions favoured by clinicians were harm reduction, counselling, medicinal cannabis and outpatient withdrawal. Counselling and outpatient withdrawal are common and effective strategies implemented in NSW Drug and Alcohol settings for addressing cannabis use disorder [62]. It remains unclear as to what harm reduction interventions regarding cannabis use in this population may look like, and while there has been some expert commentary on this issue [39], we could not identify any evaluations of harm reduction interventions in regular cannabis users, and as such—further work is required by clinicians and consumers to codesign and evaluate harm reductions in this context. Similarly, the role of medicinal cannabis treatment in OTP setting remains unclear. Despite promising findings regarding the potential for medicinal cannabis to treat cannabis withdrawal [63], cannabis use disorder [41, 64], opioid withdrawal [65] and/or comorbid health conditions, no trials have been undertaken in OTP populations, and further research is required. Despite many clinicians advocating for medicinal cannabis in OTP settings, most staff lacked confidence in delivering cannabis‐targeted interventions, highlighting the need for tailored professional development for OTP clinicians [42, 43].
In summary, this study makes several unique contributions to the existing literature on clinicians' perspectives about cannabis use. Previous research has largely focused on exploring clinicians' perspectives on the therapeutic potential of cannabis, its adverse effects, clinicians' level of knowledge [42, 43, 66] and their opinions on cannabis legalisation [42, 43]. This study explores not only addiction clinicians' attitudes towards cannabis use in OTP clients but also investigates their perspectives on patterns of cannabis use amongst their clients, perceived harms and benefits, clients' treatment‐seeking behaviours, service delivery preferences and clinicians' confidence in delivering cannabis‐related interventions.
This study will also specifically expand further on the work by Wildberger et al. [44], which explored addiction clinicians' views on cannabis. While both studies highlight mixed attitudes amongst addiction clinicians, this Australian study provides a novel insight by examining addiction clinicians' perspectives about cannabis use in their clients within the specific context of opioid treatment settings. Furthermore, while the Wildberger et al. study explored American addiction clinicians' general perspectives, this study captures and compares the perspectives of a range of Australian addiction clinicians (nurses, doctors, allied health and others) within the Australian healthcare context, providing important insights into OTP clinicians perceptions around cannabis use and its management in Australian opioid treatment settings.
The practical implications of clinicians' perspectives in this study should be considered cautiously in planning, designing and implementing novel model of cares for addressing cannabis use in OTP clients. It is crucial to understand our findings in this study represents the perspectives of addiction clinicians working in public OTP clinics. A successful holistic approach addressing cannabis use in OTP clients requires investigating all stakeholders' perspectives and needs, including clinician and OTP client perspectives. Our study group aims to understand OTP clients' perspectives on cannabis use in our future research, to co‐design a clinician‐led client service for addressing cannabis use in OTP clinics.
4.1. Limitations
Despite the high response rate to the survey and the heterogeneity of the sample in OTP clinics, participant sampling for this survey was performed through convenience sampling, and the survey was done only in a public setting on OTP clinicians, which limits the study's generalisability. This study investigated clinicians' perspectives about OTP clients' cannabis use, which may have been subject to bias on clinicians' part. It is important to calibrate clinicians' estimates of clients' cannabis use with clients' self‐reports, which will be investigated by our study group in the near future.
5. Conclusion
In summary, despite clinicians' general awareness about high levels of cannabis use amongst their OTP clients, there is uncertainty regarding the potential benefits or harms of cannabis use in OTP patients. There are low levels of clinician‐reported treatment‐seeking by clients, and low levels of confidence by many staff in implementing treatment interventions. These findings highlight the need for professional development and further research.
Author Contributions
Each author certifies that their contribution to this work meets the standards of the International Committee of Medical Journal Editors.
Conflicts of Interest
Prof Nicholas Lintzeris reports grants from the Australian National Health and Medical Research Council during the conduct of the study; and research grants from Camurus and Indivior for unrelated work. The other authors declare no conflicts of interest.
Supporting information
Data S1. Supporting Information.
Acknowledgements
We particularly wish to acknowledge the participants who generously gave their time in completing the survey. This survey was funded through the RES‐ON research funding programme (approved February 2023, application submitted November 2022). N.L. has received research funding from Camurus AB and Indivior for unrelated research and honouraria from Camurus AB for presenting educational sessions at conferences. Open access publishing facilitated by The University of Sydney, as part of the Wiley ‐ The University of Sydney agreement via the Council of Australian University Librarians.
Funding: This work was supported by the RES‐ON research funding program (approved February 2023, application submitted November 2022). N.L. has received research funding from Camurus AB and Indivior for unrelated research and honoraria from Camurus AB for presenting educational sessions at conferences.
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Associated Data
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Supplementary Materials
Data S1. Supporting Information.