Knowledge, Practices, and Attitudes of Washington State Health Care Professionals Regarding Medical Cannabis

Abstract

Introduction: Health care providers in Washington State practice in a unique environment where both medical and recreational cannabis use are legal. Five types of health care providers can authorize medical cannabis. State-certified medical cannabis consultants may advise patients in a cannabis retail store regarding use and consumption. Washington State's health care professionals' perspectives about medical cannabis can inform policy-makers nationwide who are navigating challenges posed by legalization of medical and recreational cannabis.

Materials and Methods: A cross-sectional mixed-mode survey using a 26-item questionnaire was administered to a random sample of actively licensed health care professionals legally permitted to provide medical cannabis authorizations in Washington State. We describe participant demographics and summarize responses to survey questions. We report comparisons across provider types using Fisher's exact tests with a level of significance of p<0.01.

Results: Among the 1440 health care professionals invited to participate in the study, 310 respondents met eligibility criteria (response rate 24%). Only 57 respondents (18.4%) indicated having ever issued a medical cannabis authorization. Among them, 6, all naturopaths, had provided more than 500. Over half (58%) reported that they did not feel they had the knowledge and skills necessary to provide authorizations. Depending on the condition, 29–93% of respondents correctly identified conditions that qualified a patient to receive a medical cannabis authorization. Very few knew that employers are not required to provide accommodations for medical cannabis. Health care professionals (64.8%) served as the most frequent source of information regarding cannabis risks and benefits. Over half (62%) strongly or somewhat agreed that the Drug Enforcement Agency should reschedule cannabis to make it legal at the federal level.

Conclusion: A wide range of knowledge was exhibited within our sample of health care professionals regarding qualifying conditions for medical cannabis. As more states adopt comprehensive medical cannabis laws, health care professionals must be prepared to provide information to patients regarding the effects, risks, and benefits of cannabis. Standardized education could ensure that health care professionals are prepared to responsibly promote the use of cannabis when indicated for medically appropriate symptoms and conditions. A rational approach to medical cannabis is needed to assure that unforeseen consequences are mitigated.

Introduction

Health care providers in Washington State practice in an environment in which medical and recreational cannabis use is legal. Five types of health care professionals can authorize medical cannabis.¹ The state also certifies medical cannabis consultants to advise patients in a cannabis retail store regarding medical cannabis use and consumption.² Understanding health care professionals' perspectives about medical cannabis in the current political and regulatory climate can provide guidance to health care providers and policy-makers nationwide as they navigate challenges posed by legalization of medical and recreational cannabis.

Washington State is 1 of 34 states, the District of Columbia (DC), Guam, Puerto Rico, and the Virgin Islands, with legalized medical cannabis.³ It is also 1 of 14 states and territories with legalized recreational cannabis for adults.³ Despite public controversies regarding cannabis use, few studies of U.S. health care professionals' knowledge, attitudes, and practices regarding medical cannabis have been conducted. Early studies occurred during a political and social environment substantially different from today.^4–6 More recent studies describe a range of attitudes that include support of and concern about the use of medical cannabis, lack of knowledge about the risks of cannabis, and discomfort answering patient questions about cannabis's efficacy, safety, or interactions.^7–14 A recent systematic review of the literature identified 26 studies worldwide that addressed health professionals' feelings, knowledge, and concerns. Thirteen studies were conducted in the United States; all but two included health care professionals who were ineligible to authorize medical cannabis or were conducted before the legalization of medical cannabis.¹⁵

Purpose

The purpose of this study was to investigate the knowledge, practices, and attitudes regarding medical cannabis among health care professionals in Washington State. We also identified sources of information used by health care professionals to advise patients regarding the use of cannabis for medical conditions.

Washington law

Washington State laws have changed multiple times since the original legalization of medical cannabis in 1998 that permitted medical and osteopathic physicians (MD/DO) to authorize its use.¹⁶ A 2010 bill extended the right to provide authorizations to physician assistants (PAs), advanced registered nurse practitioners (ARNPs), and naturopathic doctors (NDs).¹ Retail sale of recreational cannabis became legal in 2012 with stores opening in July 2014.¹⁷ The medical and recreational cannabis systems merged in 2015.² Additional changes to the state's law over the years include more stringent clinical care and documentation requirements.¹⁸

Washington law allows health care professionals to issue a medical cannabis authorization for a patient with a terminal or debilitating medical condition severe enough to significantly interfere with the patient's activities of daily living and ability to function. The conditions must be objectively assessed and evaluated. Qualifying conditions include cancer, human immunodeficiency virus, multiple sclerosis, epilepsy or other seizure disorder, spasticity disorders, chronic renal failure requiring hemodialysis, post-traumatic stress disorder, and traumatic brain disorder. Certain other conditions qualify if unrelieved by standard medical treatment or medication such as intractable pain, Crohn's disease, and hepatitis C with debilitating nausea or intractable pain.¹⁸ Medical cannabis may contain both tetrahydrocannabinol and cannabidiol and must be labeled to reveal the concentration of each as regulated through rules.¹⁸

Patients

There is incomplete information regarding the number and characteristics of medical cannabis patients. In accordance with a law passed in 2015, Washington established a database for medical cannabis patients implemented in 2016, which is mandatory for patients under 18 years of age and voluntary for patients aged 18 and older.¹⁸ As of October 2019, the database contained information on 39022 adults and 483 minors.¹⁹ Data on special populations other than minors, such as pregnant women and older adults, are unavailable. Public release of data is constrained by legal considerations. Aggregate information in the medical cannabis authorization database may be released if personally identifiable information is redacted only for statistical analysis and oversight of agency performance and actions.¹⁸

Health care professionals

The knowledge, practices, and attitudes of Washington State health care professionals regarding medical cannabis in the current regulatory environment remain unexplored. One Washington survey conducted before the opening of recreational cannabis retail stores identified low knowledge and comfort in recommending medical cannabis. Study participants included health care professionals who could not authorize medical cannabis, and the study was intended to inform development of an educational module.²⁰ A 2015 survey of Washington State ARNPs identified 79 of 1247 participants (6.3%) who had ever provided a medical cannabis authorization. Among these, 74 (94%) only seldom or occasionally issued an authorization.²¹ A multistate study of health professional perspectives on medical cannabis use in children with cancer conducted in 2015 included 116 participants working in a Seattle, Washington facility of which 75 were not eligible to provide authorizations. Most study participants were willing to consider medical cannabis use in children with cancer; however, analysis was not stratified by state.²²

Sources of information

Limited high-quality evidence is available to support the use of medical cannabis for most qualifying health conditions,²³ yet information abounds on websites and forums without an evidence base. A 2011 Colorado study assessed the types of information health care professionals utilized when deciding whether medical cannabis is an appropriate therapy for an authorized condition.¹¹ Providers in other states have expressed a lack of confidence in their understanding of information used to support authorization or use of cannabis for qualifying conditions.^24,25 A complicating factor in decision-making is that there may be little evidence to support cannabis use for a qualifying diagnosis, while symptoms associated with that condition, such as nausea, may have a higher degree of evidence yet not be considered a qualifying condition.²⁶

Materials and Methods

A cross-sectional mixed-mode survey was administered to a random sample of actively licensed health care professionals legally permitted to provide medical cannabis authorizations in Washington State. Lists of qualifying MDs, DOs, PAs, ARNPs, and NDs with mailing addresses in Washington, and Oregon and Idaho, to include providers who may practice in Washington, were obtained from the Washington State Department of Health. The sampling frame consisted of a stratified random sample of 360 from each group of health care professionals (Table 1).

Table 1.

Total Population (Sampling Frame) of Providers Authorized to Provide Medical Cannabis Authorizations and Survey Sample

	Total population	Survey sample
Provider type
ARNP	6658	360
MD/DO	25,649	360
ND	1208	360
PA	3419	360

Health care providers in Washington State.

ARNP, advanced registered nurse practitioner; ND, naturopathic doctor; PA, physician assistant.

The 26-item survey questionnaire was developed using prior well-validated survey instruments identified in the extant literature^8,11 and additional items developed specifically for health professionals based on Washington State cannabis laws. To address face and content validity, staff from the Washington State medical cannabis program reviewed the questionnaire. The survey instrument was then revised through iterative reviews by content experts and the research team, two of whom are Washington State ARNPs, until consensus was reached. No further psychometric testing was performed.

The survey instrument contained 25 closed-ended questions regarding knowledge of state law, attitudes about medical cannabis, and practices related to medical cannabis authorizations. For example, we asked respondents to identify from a list of conditions those that qualify an individual for a medical cannabis authorization. This required respondents to distinguish between conditions that qualify for authorization and those that do not. As another example, we asked respondents to indicate sources used to obtain information about the risks and benefits of medical cannabis. We also asked if a respondent had ever provided a medical cannabis authorization for a patient in Washington State. Demographics collected information on age, sex, race, and ethnicity. One open-ended question invited respondents to share anything they wanted about their experience authorizing medical cannabis, the findings of which will be reported elsewhere.

The survey was administered online using Qualtrics^® survey software and by mail between February 16, 2018 and April 13, 2018. Potential participants were mailed an introductory letter followed by an email message describing the study and inviting them to participate if they practiced clinically in Washington State. Both invitations included a web link and code unique to each participant for the online version of the questionnaire. Up to six additional contacts were made to nonrespondents (two postcards, three emails, and one paper questionnaire with prepaid return envelope) over the course of 8 weeks. A crosswalk file developed to send reminders to nonrespondents was destroyed at the conclusion of the survey. Participation in this study was voluntary and confidential. As an incentive, respondents could enter a raffle for one of four $100 gift cards. The university institutional review board deemed this study exempt from human subjects review.

We used Stata/MP version 15.1 to perform statistical analyses that described participant demographics and summarized responses to closed-ended survey questions using frequencies and percentages. We made comparisons across categories using Fisher's exact tests with a level of significance of p<0.01.

Results

We sent an invitation to participate in the study to 1440 health care professionals based on random selection as described, to which 398 responded. Among respondents, 69 indicated that they were not in clinical practice in Washington State, 1 moved out of state, 1 did not practice clinically, and 18 did not complete the survey; 310 respondents met eligibility criteria (response rate 24%). Naturopaths accounted for 30.3% of respondents, PAs 26.5%, ARNPs 26.8%, and MDs/DOs 16.5%. Most respondents were female (63.5% female, 35.2% male, and 0.3% other) and white/non-Hispanic (84.2%) (Table 2). The average age of respondents was 46.8 years (standard deviation, 12.4; range 25–87 years).

Table 2.

Demographics and Background of Survey Respondents: Health Care Providers in Washington State

	ARNP (N=83), %	MD/DO (N=51), %	ND (N=94), %	PA (N=82), %	Total (N=310), %
Sex
Male	19.3	70.6	21.3	45.1	35.2
Female	80.7	27.5	76.6	53.7	63.5
Other	—	—	—	1.2	0.3
Missing	—	2.0	2.1	—	1.0
Age
25–34	14.5	7.8	21.3	22.0	17.4
35–44	21.7	35.3	28.7	34.1	29.4
45–54	18.1	17.6	27.7	23.2	22.3
55–64	33.7	17.6	11.7	12.2	18.7
65+	12.0	17.6	6.4	7.3	10.0
Missing	—	3.9	4.3	1.2	2.3
Race/ethnicity (not mutually exclusive)
White	86.7	86.3	83.0	81.7	84.2
Black or African American	3.6	—	1.1	2.4	1.9
Asian	7.2	11.8	7.4	4.9	7.4
Native American/American Indian	3.6	—	—	2.4	1.6
Pacific Islander	1.2	—	—	1.2	0.6
Hispanic, Spanish, or Latino	3.6	2.0	4.3	7.3	4.5
Other	—	3.9	2.1	3.7	2.3
Missing	—	2.0	4.3	1.2	1.9
Clinical practice type
Primary care	30.1	31.4	34.0	20.7	29.0
Specialty care	68.7	68.6	64.9	79.3	70.3
Missing	1.2	—	1.1	—	0.6

Knowledge

Depending on the condition, 29–93% of respondents correctly identified a health condition that qualified a patient to receive a medical cannabis authorization. For example, 93% correctly identified cancer as a qualifying condition, while only 29% correctly identified traumatic brain injury (Table 3). A narrower range (21–53%) accurately identified conditions that do not qualify for an authorization (e.g., neurofibromatosis); 5–49% of respondents indicated that they “did not know” whether a specific condition qualified (Table 3). Parkinson's disease and rheumatoid arthritis were most frequently misidentified as qualified conditions for receiving a medical cannabis authorization, with 41.3% and 37.7% of respondents incorrectly answering that they were qualifying conditions, respectively.

Table 3.

Knowledge Regarding Qualified Conditions for Medical Cannabis Among Health Care Providers in Washington State, 2018 (N=310)

Condition	Qualified condition	Correctly identified		Incorrectly identified		Don't know/missing
		n	%	n	%	n	%
Cancer	Yes	289	93.2	6	1.9	15	4.8
Intractable paina	Yes	248	80.0	16	5.2	46	14.8
Nauseab	Yes	239	77.1	22	7.1	49	15.8
Crohn's diseasec	Yes	237	76.5	19	6.1	54	17.4
Glaucomad	Yes	215	69.4	28	9.0	67	21.6
Hepatitis Ce	Yes	201	64.8	35	11.3	74	23.9
Epilepsy or other seizure disorder	Yes	195	62.9	40	12.9	75	24.2
Depression	No	165	53.2	54	17.4	91	29.4
HIV	Yes	156	50.3	55	17.7	99	31.9
Spasticity disorders	Yes	154	49.7	45	14.5	111	35.8
Multiple sclerosis	Yes	151	48.7	44	14.2	115	37.1
Anxiety	No	130	41.9	106	34.2	74	23.9
Post-traumatic stress disorder	Yes	118	38.1	78	25.2	114	36.8
Traumatic brain injury	Yes	90	29.0	83	26.8	137	44.2
Lupus	No	81	26.1	83	26.8	146	47.1
Tourette's syndrome	No	78	25.2	79	25.5	153	49.4
Rheumatoid arthritis	No	73	23.5	117	37.7	120	38.7
Neurofibromatosis	No	66	21.3	102	32.9	142	45.8
Parkinson's disease	No	64	20.6	128	41.3	118	38.1

^aIntractable pain unrelieved by standard medical treatments and medications.

^bDiseases, including anorexia, which result in nausea, vomiting, wasting, appetite loss, cramping, seizures, muscle spasms, or spasticity, when these symptoms are unrelieved by standard treatments or medications.

^cCrohn's disease with debilitating symptoms unrelieved by standard treatments or medications.

^dGlaucoma either acute or chronic, with increased intraocular pressure unrelieved by standard treatments and medications.

^eHepatitis C with debilitating nausea or intractable pain unrelieved by standard treatments or medications.

An important aspect of health care professionals' knowledge is related laws and regulations, including the sale and possession of medical cannabis and protections for health care professionals. For most items, the majority of respondents indicated that they did not know whether the statement was correct (Table 4). For example, overall, 60% of respondents did not know whether the statement, “all qualifying patients may possess the same amounts of cannabis products” was incorrect (26.1% answered correctly and 12.3% answered incorrectly) (Table 4). A significantly greater proportion of health care providers who had ever provided a medical cannabis authorization for a patient in Washington State (N=57) correctly identified most authorization and related requirements compared to those who had never provided an authorization (N=251) (Table 4, p<0.01). For example, when asked if all patients with an authorization may possess the same amount of cannabis, 43.9% of providers who had issued an authorization correctly answered “No,” compared to 22.3% of providers who had never provided medical cannabis authorization in Washington (p<0.01).

Table 4.

Health Care Provider Knowledge About Authorizing the Use of Medical Cannabis in Washington State, 2018

Authorization terms for medical cannabis use	Ever provided medical cannabis authorization for patient in Washington State
	Yes (n=57), %	No (n=251), %	Missing (n=2), %	Total N=310, %	p-value*
Employers must provide a workplace accommodation (correct response: no)					<0.01
Answered incorrectly	7.0	6.0	—	6.1
Answered correctly	52.6	31.1	—	34.8
Did not know	40.4	61.4	50.0	57.4
Missing	—	1.6	50.0	1.6
Health plans are liable for reimbursement (correct response: no)					<0.01
Answered incorrectly	5.3	4.8	—	4.8
Answered correctly	66.7	35.5	—	41.0
Did not know	28.1	58.2	50.0	52.6
Missing	—	1.6	50.0	1.6
All qualifying patients may possess the same amounts of cannabis products (correct response: no)					<0.01
Answered incorrectly	17.5	11.2	—	12.3
Answered correctly	43.9	22.3	—	26.1
Did not know	38.6	64.9	50.0	60.0
Missing	—	1.6	50.0	1.6
Health care professional may recommend qualifying patient to grow or possess more cannabis than allowed (correct response: yes)					<0.01
Answered incorrectly	29.8	37.5	—	35.8
Answered correctly	54.4	11.6	—	19.4
Did not know	15.8	49.4	50.0	43.2
Missing	—	1.6	50.0	1.6
All children under age 18 must be in the database (correct response: yes)					0.35
Answered incorrectly	7.0	2.8	—	3.5
Answered correctly	54.4	55.0	—	54.5
Did not know	38.6	39.8	50.0	39.7
Missing	—	2.4	50.0	2.3
All adults must be in the database (correct response: no)					<0.01
Answered incorrectly	29.8	63.7	—	57.1
Answered correctly	38.6	3.2	—	9.7
Did not know	31.6	31.5	50.0	31.6
Missing	—	1.6	50.0	1.6
A person supervised for a criminal conviction may never be a qualifying patient (correct response: no)					0.11
Answered incorrectly	12.3	15.1	—	14.5
Answered correctly	40.4	25.5	—	28.1
Did not know	47.4	57.8	50.0	55.8
Missing	—	1.6	50.0	1.6
All health care professionals are not subject to criminal sanctions or civil consequences for advising a patient about medical cannabis (correct response: no)					0.54
Answered incorrectly	45.6	39.8	—	40.6
Answered correctly	21.1	18.3	—	18.7
Did not know	33.3	40.6	50.0	39.4
Missing	—	1.2	50.0	1.3
Selling or donating topical products with a THC concentration <0.3% to qualifying patients (correct response: yes)					<0.01
Answered incorrectly	31.6	30.7	—	30.6
Answered correctly	29.8	8.8	—	12.6
Did not know	38.6	59.0	50.0	55.2
Missing	—	1.6	50.0	1.6

^*p-Value indicates significance in variation of distribution across categories (excluding missing observations) using Fisher's exact tests.

THC, tetrahydrocannabinol.

Sources of information

Participants were asked to indicate all sources of information used to determine the risks and benefits of medical cannabis. Other licensed health care professionals served as the source of information for 64.8% of respondents. Continuing education (48.1%) and scientific journals (31.0%) were also identified as frequently accessed sources of information. Fewer respondents reported accessing information from medical cannabis consultants (10.3%), family and friends (6.1%), and books (2.3%).

Attitudes

The majority of respondents (83.2%) strongly or somewhat agreed that health care professionals should have content about medical cannabis as part of their education. Nearly two-thirds (62.5%) strongly or somewhat agreed that the Drug Enforcement Agency should reschedule cannabis to make it legal at the federal level. The use of medical cannabis to reduce opioids for chronic noncancer pain was endorsed by 71.5% of respondents, although 69.7% strongly or somewhat agreed that cannabis can be addictive. While 28.0% believed that medical cannabis can provide significant benefit to people with mental health problems, 52.0% also believed that it posed a significant mental health risk (Fig. 1).

FIG. 1.

Washington State health care provider attitudes toward cannabis and medical cannabis, 2018. * indicates percentages under 6.0%.

Practices

Registration in the state's database is voluntary for adult medical cannabis patients and mandated for patients under age 18. Very few (<0.1%) respondents reported having ever checked the medical cannabis database to determine if a patient was registered. Seventeen percent had completed a continuing education course on medical cannabis, and half stated that they were not at all familiar with the Washington State Medical Marijuana Guidelines. Some respondents (32%) noted a decrease in the number of requests for medical cannabis authorizations since retail cannabis became available in 2014 while others did not know if there was a change (37%).

Only 57 respondents (18.5%) had ever issued a medical cannabis authorization. Among them, three were unsure how many authorizations they had provided; 29 had provided fewer than 10; and 12 had provided 10–50. Five had provided 51–100, 2 had provided 101–500, and 6 had provided more than 500, all naturopaths. When asked about the frequency with which they performed clinical practices required by law to issue an authorization, most respondents (84.2–89.5%) stated that they always or very often performed required practices. The two exceptions were that only 44.1% completed an in-person examination every 6 months to renew a minor's authorization and 49.1% discussed with a qualifying patient how to use cannabis. A smaller percentage reported always or very often performing practices recommended in the literature, such as screening for substance misuse (50.0%), requiring a medical cannabis agreement (20.0%), performing a pregnancy test on a female (22.2%), or advising about the effects of cannabis on the developing brain (45.2%) (Table 5).

Table 5.

Reported Use of Required and Recommended Practices Among Washington State Health Care Professionals with a History of Providing a Medical Cannabis Authorization

	Percentage of respondents			Total respondents (N)
	Always or very often (%)	Often or sometimes (%)	Rarely or never (%)
Required practices
Advised a patient about the risks and benefits of medical use of cannabis	89.5	7.0	3.5	57
Complete an in-person physical examination	89.5	7.0	3.5	57
Document measures other than cannabis used to treat the terminal or debilitating medical condition	89.5	7.0	3.5	57
Complete an in-person physical examination at least annually to renew an adult's authorization	87.7	7.0	5.3	57
Document the terminal or debilitating medical condition in patient's medical record	87.7	5.3	7.0	57
Documented relationship as principal care provider for the patient's terminal or debilitating medical condition	86.0	8.8	5.3	57
Inform patient of other options for treatment	86.0	10.5	3.5	57
Complete an authorization on form	84.2	1.8	14.0	57
Discussed how to use cannabis	49.1	21.1	29.8	57
Complete an in-person physical examination at least every 6 months to renew a minor's authorization	44.4	4.4	51.1	45
Recommended practices
Performed mental health screen for problems such as depression and anxiety screening	53.6	32.1	14.3	56
Performed screening for substance misuse	50.0	16.7	33.3	54
Advised patient to seek advice on specific cannabis products from the retail store	49.1	40.0	10.9	55
Discussed types of products the qualifying patient should seek from a retail outlet.	45.5	27.3	27.3	55
Provided counseling to breastfeeding women about potential effects to a child	45.2	9.5	45.2	42
Provided counseling about long term effects of cannabis on the developing brain	45.2	14.3	40.5	42
Obtained urine or blood screening for substance misuse	22.9	18.8	58.3	48
Performed a pregnancy test for a female	22.2	14.8	63.0	54
Required a medical cannabis agreement similar to a controlled substance agreement	20.0	5.5	74.5	55

Those who did not provide medical cannabis authorizations were asked to report all reasons why. More than half (58%) reported that they did not feel they had the knowledge and skills necessary to provide authorizations. More than one-third (38%) reported that their practice had a policy prohibiting medical cannabis authorizations, and 21% indicated that their practice received federal money. Thirty-two percent had concerns about medical cannabis use, 31% had never had a request, 22% indicated concerns about legal problems, and 16% had concerns about a lack of evidence base for medical cannabis use. An additional 20% (N=51) indicated “other reason.”

Discussion

Among licensed health care professionals, only 18.5% reported having ever provided authorizations for medical cannabis of which the majority (68%) were NDs. The higher proportion of NDs was anticipated based on the number of NDs identified in the Washington State database as authorizing medical cannabis. In 2017, for example, 219 of 1387 (15.8%) licensed NDs were in the database as having provided a medical cannabis authorization. In comparison, 648 of 28,160 (2.3%) licensed MDs were in the database. It is not known based on our results if patients are going to NDs specifically for medical cannabis authorization outside of their allopathic care provider or if more NDs overall recommend medical cannabis to their established patients.

Barriers to receiving an authorization

The reported reasons why respondents do not provide authorizations included knowledge deficits and legal concerns, coupled with concerns about the potential negative health effects of cannabis. These findings explain why some allopathic health care providers in Washington State are reluctant to authorize cannabis for medical use and it is clear some clinics prohibit the practice. Consequently, patients may face barriers to initiating discussions with their health care provider regarding cannabis use. This can be a particular concern for elderly patients, who strongly support the use of medical cannabis for pain relief, appetite loss, and anxiety, but are reluctant to use it without an explicit recommendation from their clinician.²⁷ Patients may instead obtain recreational cannabis from retail stores or unsanctioned sources for symptom management. By limiting conversations about medical cannabis, providers forfeit an opportunity to advise caution regarding potential risks, interactions with current medications, or to suggest alternative treatment options.

More than a third of respondents stated that they had never had a request for medical cannabis, yet a recent survey of 150 Washington State adult patients with chronic pain found that nearly 70% reported cannabis use.²⁸ In that sample, pain was the most frequently cited reason for cannabis use (67.2%) followed by sleep (58.2%) and recreation/social use (49.3%).²⁸ Only 10% of those respondents indicated having a current medical cannabis authorization, suggesting that patients may be reluctant to discuss their cannabis use with providers even when they are using it for symptom control.

Knowledge of qualifying conditions

In assessing knowledge, respondents most accurately identified qualifying conditions unrelieved by standard treatment, such as cancer and intractable pain. This result may be influenced by Washington State's regulatory requirement for continuing education regarding the use of opioids for the management of chronic noncancer pain.²⁹ Some continuing education courses on pain management incorporate information on nonprescription options for pain relief, including medical cannabis.^30,31 We noted that knowledge of other qualifying conditions varied widely. There is no required education on this topic for health care professionals. Consequently individuals may choose whether to increase their knowledge on the subject. There was a particular lack of knowledge of post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI) as qualifying conditions, the two most recently added to the law, as well as common misidentification that anxiety and depression are qualifying conditions for medical cannabis which they are not.²³ The evidence is inconclusive at present regarding cannabis's effect on depression and anxiety according to a compilation of evidence from the National Academies of Sciences, Engineering and Medicines in 2017.²³ While some immediate benefits to mood have been reported, long-term or heavy cannabis use, considered use on more than 20 of the last 30 days, has been linked to increased social anxiety and increased risk of suicide attempt and completion.²³ Although patients report using cannabis for relief of depressive symptoms, no well-controlled studies demonstrate efficacy, and some evidence finds that childhood anxiety and depression are risk factors for problematic cannabis use.²³

Employment and medical cannabis

Employment-based drug testing, particularly in the context of legal medical and recreational cannabis, has become a complex issue with multiple court challenges. There is no legal requirement in Washington for employers to accommodate the authorized use of medical cannabis. Very few (34.8%) survey respondents were aware of this. This knowledge deficit could impact patient care regardless of whether the practitioner authorizes medical cannabis. Patients should be informed that there are potential consequences in the employment setting even when using medical cannabis with authorization. In states with both recreational and medical cannabis, laws on drug testing can be particularly complex and important to health care conversations.

Sources of information

According to our survey, health care professionals typically do not use medical cannabis consultants as an information resource. Health care professionals rely most on other health care professionals and continuing education for their information on cannabis. Nonetheless, fewer than half received continuing education on medical cannabis. Research demonstrates, however, that deficiencies in both continuing education and health care professionals' knowledge can create barriers to offering cannabis as an option for medical use.²⁸ An example of a deficiency is that about one-quarter were uninformed about the possibility of cannabis use disorder, suggesting that health care professionals require more evidence-based medical cannabis education, which incorporates information about the potential for and assessment of cannabis use disorder.

Limitations

The study had several limitations. First, the survey relied upon self-report and could be subject to social desirability bias if respondents felt compelled to provide responses that they believed others would prefer. Second, this study was cross-sectional and therefore did not allow for comparison of knowledge, attitudes, or beliefs over time. Third, because data on nonrespondents' demographics or practices were not available, it was not possible to assess whether respondents differed characteristically from nonrespondents (e.g., by age). Random selection of study participants from a large sampling frame was used to reduce risk of selection bias. The response rate of 24% is lower than preferred, yet a strength of this study was the use of random sampling versus convenience sampling more frequently used in other studies.^10,11,14,24 The generalizability of this study is limited as the instrument was designed specifically for Washington State licensed health care professionals in active practice. Comparison between and among states with medical cannabis laws is challenging because not all states allow the same five types of health care professionals to provide authorizations, especially naturopaths who are regulated in fewer than half of the U.S. jurisdictions. This study is an important first step toward evaluating how multiple types of health care professionals adjust to significant changes in law and practice norms regarding cannabis.

Implications

Medical cannabis laws in Washington State have become more comprehensive over time. These efforts set clearer and more rigorous standards for provider–patient interactions and to increase patient safety. For example, legislation in 2015 mandated an expiration period for an authorization, required that children be entered into the state's database, and required a patient's evaluation to occur in person. In contrast, some changes to the law are not supported by strong evidence, such as the addition in 2015 of PTSD and TBI as qualifying conditions. Areas for improvement in clinical practice include the need to assure that health care professionals are knowledgeable about the law, use evidence-based information for decision-making, and use best practices for patients across the life span with regards to cannabis use.

Self-management with cannabis

Legalization of recreational cannabis has allowed people to self-manage symptoms with cannabis using little evidence to guide choices about cannabis products while removing health care professionals from their decision-making. As states have liberalized cannabis laws, they have also significantly restricted access to opioids. Studies indicate that individuals prescribed opioids who may be having difficulty gaining access to them are using cannabis for symptoms such as pain, anxiety, disturbed sleep, and withdrawal.^32,33 Among those who use cannabis for medical purposes, pain is among the most frequently cited reasons for use.³⁴ Whether these practices help or hinder opioid use remains in dispute, although one recent report suggests that legal access to cannabis is associated with increased opioid overdose mortality.³⁵

Cannabis has physical and psychological effects that may impact known or unknown preexisting conditions (e.g., psychosis). After recreational legalization in Colorado, an increase was observed in cannabis-related emergency department visits for vomiting, racing heart, and psychotic symptoms.³² This parallels adverse effects reported by individuals with chronic pain who choose to self-medicate with cannabis and experience physiological, mental health, and socioeconomic concerns.³³ Social stigma and lack of approval from health care providers have also been reported, which may prevent patients from disclosing symptoms and cannabis use to alleviate them.³³

Recommendations

It is critical to incorporate evidence-based guidance regarding medical cannabis into health professional education. The Washington State Department of Health has adopted and accredited an optional continuing education module on medical cannabis for currently practicing clinicians.³⁶ Regulations could require, rather than recommend, that health care professionals who issue authorizations complete a continuing education course and periodic reeducation. The state's law could also be revised to stipulate practice requirements for special populations such as pregnant women and children with a qualifying condition for cannabis use. Perspectives of health professionals may be contradictory, as noted in Figure 1, where 71.5% endorsed cannabis use for pain, but just as many thought that cannabis has the potential to be addictive. Opposing views such as these likely complicate decisions about offering medical cannabis as an option for patients with poorly controlled symptoms.

To assure that information used by providers for decision-making is the highest level of evidence and quality, work groups could critique and regularly update sources of information for health care professionals. In addition, a medical cannabis shared decision-making model could be developed to help guide providers in their conversations with patients on topics, including laws, health benefits and risks, pregnancy and driving precautions, and sources for safe purchase of products. A model medical cannabis use agreement, comparable to opioid use agreements, could be an adjunct to a shared decision-making process.³⁷

Conclusion

The escalation in the number of states with comprehensive medical cannabis laws has created new demands on health care professionals. Patients expect their clinician to provide information on the effects, risks, and benefits of cannabis. Health care professionals must be prepared to meet their expectations and to do so within the letter of the law. Now more than ever, a rational approach to medical cannabis is needed to assure that unforeseen consequences are mitigated while responsibly promoting the use of cannabis for medically appropriate symptoms and conditions.

Abbreviations Used

ARNP

advanced registered nurse practitioner

ND

naturopathic doctor

PA

physician assistant

PTSD

post-traumatic stress disorder

TBI

traumatic brain injury

THC

tetrahydrocannabinol

Author Disclosure Statement

No competing financial interests exist.

Funding Information

This investigation was supported, in part, by funds provided by the State of Washington Initiative Measure No. 502.

Cite this article as: Kaplan L, Klein T, Wilson M, Graves J (2020) Knowledge, practices, and attitudes of Washington State health care professionals regarding medical cannabis, Cannabis and Cannabinoid Research 5:2, 172–182, DOI: 10.1089/can.2019.0051.