Abstract
Introduction
While marijuana has been legal for medical purposes in California since 1996, little is known about the health histories of young adult medical marijuana patients who are a significant proportion of medical marijuana patients. We examine whether young adult medical marijuana patients report health conditions and motivations for use that were consistent with medical use of marijuana in California.
Methods
Young adults (N=366) aged 18 to 26 years old were sampled in Los Angeles in 2014–15 and segmented into medical marijuana “patients” (n=210), marijuana users with a current recommendation and non-patient users or “non-patients” (n=156), marijuana users who never had a medical marijuana recommendation. Differences between patients and non-patients regarding self-reported health histories and past/current motivations for marijuana use were expressed as unadjusted risk ratios.
Results
Compared to non-patients, patients were significantly more likely to report a range of lifetime health problems, such as psychological, physical pain and gastrointestinal. In the past 90 days, patients were significantly more likely to report motivations for marijuana use than non-patients concerning sleep, anxiety, physical pain and focusing. Psychological and pain problems were the most common health conditions reported to receive a medical marijuana recommendation. Patients were significantly less likely than non-patients to report any privacy concerns about obtaining a medical marijuana recommendation.
Conclusions
Patients were significantly more likely to report a range of health conditions and motivations associated with medical use than non-patients. A great majority of patients reported obtaining a medical marijuana recommendation for health problems in accordance with California law.
Keywords: medical marijuana, young adults, physical health, psychological health
Introduction
The use of marijuana for medical purposes is now legal in 28 out of 50 states (plus the District of Columbia) in the US, [1] a trend including 16 states that have legalised marijuana for medical purposes since 2010. California, the most populous state in the US with 38.3 million citizens, was the first to legalise marijuana for medical purposes in 1996 and has one of the broadest definitions of health conditions for which a physician can recommend medical marijuana: “cancer, anorexia, AIDS, chronic pain, spasticity, glaucoma, arthritis, migraine, or any other illness for which marijuana provides relief” [2]. Since 1996, results from more than 40 clinical trials indicate that marijuana (cannabis) and cannabinoids can be effective in the treatment of several physical conditions, including chronic pain, neuropathic pain, spasticity associated with multiple sclerosis, and nausea [3]. Similarly strong clinical evidence is lacking in support of marijuana’s effectiveness in treating some psychiatric conditions, such as post-traumatic stress disorder, agitation in Alzheimer’s disorder and Tourette’s disorder [4]. However, a survey of California physicians who recommended medical marijuana to patients reported effectiveness for a range of conditions, including post-traumatic stress disorder, depression, anxiety and insomnia [5].
A high proportion of early medical marijuana patients (henceforth referred to as “patients”) in California were HIV positive or diagnosed with AIDS and used marijuana to treat nausea and wasting syndrome [6–8]. A shift towards treating pain and psychological conditions, which is allowed under California law, began in the 2000s among patients [9,10], and were the primary indications among more recent studies reporting health conditions of patients [11–14]. Across all periods of research in the US, patients were predominantly white, male and over 35 years old [8,10–14], which leaves large gaps in understanding the health of non-whites, women and young adult patients, who represent a significant proportion of the broader population of medical marijuana patients [15].
Adolescents and young or emerging adults, commonly defined as persons aged 18 to 25 years old [16], report a variety of psychological and physical problems according to U.S. and international studies. These problems include: anxiety, mood, impulse-control, and substance use [17]; physical pain [18], such as back pain and musculoskeletal complaints [19]; abdominal pain and irritable bowel syndrome symptoms [20]; and asthma [21]. Overall, approximately 15% of young adults reported at least one chronic medical condition in 2004–2006 [22]. The prevalence of psychological and physical problems among young adults is likely greater than reported estimates as suggested by high rates of misuse of prescription medications for the purposes of self-medication [23–27].
Among young adults, 19.6% (6.8 million persons) reported using marijuana in the past month in 2014, which is the highest rate among any age group in the US [28]. Nearly all research to date on health among young adult marijuana users has focused on illicit, recreational or non-medical use. Overall, studies indicate that these young adult non-patient marijuana users or “non-patients”, as a consequence of non-medical marijuana use, are at an increased risk for: physical ailments (e.g. respiratory problems, pulmonary effects), psychological problems (e.g., depression, anxiety, insomnia; drug dependence), criminal justice involvement, as well as lower academic achievement and functioning [29–40]. Other studies of young non-patients indicate that some psychological problems precede [41–42] rather than precipitate marijuana use, suggesting that marijuana may be used as a coping tool for some psychological problems. Similarly, results from a subsample of young adult patients indicate that psychological problems were the primary reasons for current marijuana use [13]. While data on young adult patients is very limited, these studies suggest some similarities in motives for marijuana use between young patients and non-patients. No studies have compared motives for marijuana use or health histories between young adult patients and non-patients.
Stigma may be associated with becoming a patient or using marijuana as a patient [43], as evidenced by the fact that while 5.9% of Californians report ever having “used marijuana medically” [15] only approximately 2.0% have received a medical marijuana recommendation [44]. For instance, there is a perception that rather than having bonafide health problems and using marijuana for its medical properties, patients are primarily taking advantage of the law to use marijuana recreationally [45]. This perception may extend even more so to young patients given that young adults report the highest rates of illicit marijuana use among any age group [28]. No studies have examined the health conditions reported by young adult patients to physicians, how these health conditions compare to permissible health conditions for medical marijuana under California law, or factors that might discourage young adults from seeking a medical marijuana recommendation.
Since much is known about young adult non-patients and little is known about young adult patients, we undertook a descriptive analysis of young adult patients and non-patients in Los Angeles, California with several objectives focusing on health: (i) compare demographic characteristics and health histories; (ii) compare past and current motivations for marijuana use; (iii) compare concerns relating to seeking a medical marijuana recommendation; and (iv) among patients, report health conditions indicated to physicians when obtaining their recommendation and assess the veracity of these health conditions. Overall, these objectives will inform the broader aim of determining whether young adult patients report health conditions and motivations for use that are consistent with medical use of marijuana in California, which is relevant for understanding if policies allowing for access to medical marijuana are reaching their intended target.
Methods
Sample
Participants (N=366) were recruited and interviewed in Los Angeles between February 2014 and April 2015. Enrolment criteria included the following: aged between 18 and 26 years old; used marijuana at least four times in the last 30 days; lived in the Los Angeles metro area; and spoke/read English. Additionally, the sample was stratified based upon whether young adults had a current medical marijuana recommendation issued by a California-based physician, i.e. medical marijuana patients (n=210), or not, i.e. non-patient users (n=156). Additionally, non-patients enrolled in the study were restricted to only those who had never received a medical marijuana recommendation.
Interviewers used targeted [46] and chain referral [47] sampling to recruit participants in natural settings, such as parks, streets, college campuses and medical marijuana dispensaries. Additionally, recruitment flyers were posted in public locations across the Los Angeles area and on Craigslist. Young persons who were screened for eligibility received a $3 gift card while persons who qualified and were interviewed received a $25 cash incentive.
Of the 710 individuals who were screened, 436 (61.4%) met the study eligibility requirements. Among the 180 non-patients who met eligibility requirement, 156 (86.7%) were enrolled in the study. Among the 256 patients who met eligibility requirements, 210 (82.0%) were enrolled in the study. No statistically significant differences (i.e. age, gender, race/ethnicity) were found between individuals enrolled and not enrolled in the study.
Data Collection
The study instrument was developed using Research Electronic Data Capture (REDCap). Interviews were conducted in semi-private locations in the neighbourhoods where participants were recruited or lived. Most questions were administered face-to-face with the exception of psychometric scales and sensitive questions involving sexual behaviour, which were self-administered. Informed consent of all participants was obtained prior to the start of each interview. All study procedures were approved by the Institutional Review Boards at Children’s Hospital Los Angeles and Drexel University.
Measures
Sociodemographic data were captured using structured questions about age, gender, sexual identity, race/ethnicity, education, employment and insurance coverage [24]. History of arrest for marijuana possession and history of submitting to a drug test for marijuana use were also measured.
Questions assessing lifetime health problems were adapted from prior studies of medical marijuana patients [7,9] and based upon conditions found in the International Classifications of Diseases (ICD-9). To determine lifetime physical and psychological health, all participants were asked, Have you ever experienced any physical or psychological problems in the following areas? Affirmative responses resulted in follow-up questions such as, What kind of mood or other psychological conditions have you experienced?
Questions assessing motivations for marijuana use were adapted from marijuana motivation scales primarily focused on non-medical use [44,45] and research focused on medical use [5,9]. To assess motivations for marijuana use during adolescence (defined here as before the age of 19), all participants were asked, During this period, what were the reasons you used marijuana? Response options included both medical motivations that improve both physical and mental health, and non-medical motivations. For recent marijuana use, all participants were asked, What are some of the reasons you used marijuana in the past 90 days?
To assess concerns relating to seeking a medical marijuana recommendation, participants we asked, Do you have any of the following privacy concerns about obtaining a doctor’s recommendation for medical marijuana? Response options included items related to participant’s name being stored in a state database and employer, family and government finding out about the medical marijuana recommendation.
To document the condition patients received the medical marijuana recommendation for, patients only were asked, What was the main or primary health condition – the problem that was giving you the most difficulties – that the doctor made the medical marijuana recommendation for? To assess whether patients had ever received prior medical attention for a health condition, patients were asked, Did you ever receive a diagnosis for this primary health condition? To assess whether the health condition reported to a doctor for the medical marijuana recommendation was legitimate or not, patients were asked, Was this a genuine health condition that you reported to the doctor? To assess reasons for current marijuana use, patients were asked, What are the conditions or reasons you are currently using marijuana for?
Data Analysis
Means and frequencies of variables of interest were calculated to describe the study sample. Differences between patients and non-patients were assessed using Pearson’s χ2-tests and independent sample t-tests. Unadjusted risk ratios and their 95% confidence intervals were calculated from contingency table analyses to compare patients and non-patients on binary variables. A preliminary investigation of the relationships between demographic variables (e.g. age, gender, race/ethnicity) and outcomes of interest (e.g. physical/psychological problems) did not reveal significant findings. Therefore, risk ratios were not adjusted for demographic variables. To correct for the large number of statistical tests performed, we followed the Benjamini-Hochberg procedure [50] which involved ranking observed P values in ascending order, computing an adjusted p-value based on the ranking position of the observed p-value in the test, and comparing the observed p-value to the False Discovery Rate (FDR) of 0.05. Using this procedure, three statistically significant results fell below α≤0.05 and were omitted. All analyses were performed using SPSS, version 23.0 (SPSS Inc., Chicago, IL, USA) in 2015–16.
Results
Overall, the average age of the sample was 21.2 years old, two-thirds were men, 82% identified as heterosexual, and Hispanics comprised the largest ethnic group (see Table 1). No significant differences were found between patients and non-patients across these key demographic variables. However, patients were significantly more likely to both have not applied for a job out of fear of failing a drug test and to have failed a drug test for marijuana compared to non-patients.
Table 1.
Sociodemographics and medical marijuana patient status (N=366)
| Variable | Patients n=210 % (n) |
Non-Patients n=156 % (n) |
Total N=366 % (n) |
Unadjusted risk ratios (95%CI) |
|---|---|---|---|---|
| Age, mean (sd) | 21.4 (2.47) | 20.9 (2.46) | 21.2 (2.47) | t(364)=1.84a |
|
Gender/sex at birth Male |
68.1 (143) | 63.5 (99) | 66.1 (242) | 1.1 (0.9–1.3) |
|
Sexual identity Heterosexual |
80.5 (165) | 82.7 (124) | 81.9 (289) | 0.9 (0.8–1.2) |
| Ethnicity | ||||
| Hispanic/Latinob | 43.7 (90) | 48.1 (74) | 45.6 (164) | 0.9 (0.8–1.1) |
| Non-Hispanic race | ||||
| White | 28.6 (59) | 21.4 (33) | 25.6 (92) | 1.2 (1.0–1.4) |
| Black/African American | 17.5 (36) | 20.8 (32) | 18.9 (68) | 0.9 (0.7–1.2) |
| Multiracial | 5.8 (12) | 6.5 (10) | 6.1 (22) | 1.0 (0.6–1.4) |
| Asian/Pacific Islander | 4.4 (9) | 3.2 (5) | 3.9 (14) | 1.1 (0.8–1.7) |
| Education/employment history | ||||
| Some college or above | 73.3 (154) | 68.4 (106) | 71.2 (260) | 1.1 (0.9–1.4) |
| Currently in school/educational program | 66.2 (137) | 71.8 (112) | 68.6 (249) | 0.9 (0.7–1.1) |
| Employed | 56.2 (118) | 48.1 (75) | 52.7 (193) | 1.2 (1.0–1.4) |
| Ever not applied for a job due to fear of failing a drug test from marijuana use | 51.0 (107) | 33.3 (52) | 43.4 (159) | 1.4 (1.1–1.6)** |
| Ever tested positive for marijuana during drug testc | 20.0 (42) | 8.3 (13) | 15.0 (55) | 1.4 (1.2–1.7)* |
| Current health insurance | 77.1 (155) | 78.1 (118) | 77.6 (273) | 1.0 (0.8–1.2) |
| Ever arrested | 40.5 (85) | 34.2 (53) | 37.8 (138) | 1.1 (0.9–1.3) |
| Ever arrested for marijuana possessiond | 10.5 (22) | 4.5 (7) | 7.9 (29) | 1.4 (1.1–1.7) |
Boldface indicates statistical significance:
P<0.05,
P<0.01
Indicates t-test statistic (degrees of freedom)
Among Hispanic/Latinos, participants also identified as: Multiracial (N=26), White (N=9), Native American (N=2), and Black (N=1).
The percentage is based on entire sample but only 59 people who ever failed a drug test for a job application or any other reason received this question.
The percentage is based on entire sample but only 37 people who had ever had a marijuana-related arrest received this question.
The most common lifetime health problems across all participants were psychological and pain followed by gastrointestinal, neurological and drug/alcohol problems (see Table 2). Compared to non-patients, patients were significantly more likely to report all of these lifetime problems: psychological, pain, gastrointestinal, neurological, and drug/alcohol problems. Within these categories, the top health problems reported by patients included insomnia, anxiety, depression, non-specific pain, nausea, lower back pain, migraines, and attention deficit hyperactivity disorder (ADHD). One patient reported being HIV positive. Top health problems reported by non-patients were insomnia, non-specific pain, anxiety, and depression.
Table 2.
Lifetime physical or psychological problems (N=366)
| Variable | Patients n=210 % (n) |
Non-patients n=156 % (n) |
Total N=366 % (n) |
Unadjusted risk ratios (95% CI) |
|---|---|---|---|---|
| Psychological problems | 88.6 (186) | 65.4 (102) | 78.7 (288) | 2.1 (1.5–3.0)*** |
| Insomnia | 73.3 (154) | 48.7 (76) | 62.8 (230) | |
| Anxiety | 60.5 (127) | 37.2 (58) | 50.5 (185) | |
| Depression | 52.9 (111) | 33.3 (52) | 44.5 (163) | |
| ADHD | 22.9 (48) | 13.5 (21) | 18.9 (69) | |
| Post-traumatic stress | 11.9 (25) | 1.9 (3) | 7.7 (28) | |
| Pain | 84.8 (178) | 67.9 (106) | 77.6 (284) | 1.6 (1.2–2.1)** |
| Non-specific pain | 51.9 (109) | 46.2 (72) | 49.5 (181) | |
| Lower back pain | 27.6 (58) | 15.4 (24) | 22.4 (82) | |
| Injury | 13.8 (29) | 7.7 (12) | 11.2 (41) | |
| Pre-menstrual stress | 9.5 (20) | 3.8 (6) | 7.1 (26) | |
| Skeletal | 8.1 (17) | 4.5 (7) | 6.6 (24) | |
| Spinal | 7.6 (16) | 4.5 (7) | 6.3 (23) | |
| Chronic regional pain syndrome | 6.2 (13) | 3.8 (6) | 5.2 (19) | |
| Sprain | 4.8 (10) | 2.6 (4) | 3.8 (14) | |
| Scoliosis | 2.9 (6) | 3.2 (5) | 3.0 (11) | |
| Arthritis | 2.4 (5) | 0 | 1.4 (5) | |
| Gastrointestinal problems | 41.9 (88) | 23.7 (37) | 34.2 (125) | 1.4 (1.2–1.6)** |
| Nausea | 31.9 (67) | 16.7 (26) | 25.4 (93) | |
| Other intestinal | 12.9 (27) | 8.3 (13) | 10.9 (40) | |
| Peptic ulcer | 1.9 (4) | 0.6 (1) | 1.4 (5) | |
| Gastritis | 1.4 (3) | 0 | 0.8 (3) | |
| Neurological problems | 24.3 (51) | 12.2 (19) | 19.1 (70) | 1.4 (1.1–1.6)* |
| Migraine or headaches | 22.9 (48) | 12.2 (19) | 18.3 (67) | |
| Head or brain injury | 1.9 (4) | 1.3 (2) | 1.6 (6) | |
| Drug/alcohol dependence | 16.7 (35) | 5.8 (9) | 12.0 (44) | 1.5 (1.2–1.8)* |
| Other illicit drug | 8.6 (18) | 3.2 (5) | 6.3 (23) | |
| Alcohol | 6.7 (14) | 1.9 (3) | 4.6 (17) | |
| Prescription opioids | 2.9 (6) | 0.6 (1) | 1.9 (7) | |
| Other prescription drug | 2.9 (6) | 0.6 (1) | 1.9 (7) | |
| Heroin | 0.5 (1) | 0.6 (1) | 0.5 (2) | |
| Other chronic medical conditions | 5.2 (11) | 1.3 (2) | 3.6 (13) | 1.5 (1.2–1.9) |
| Asthma | 3.8 (8) | 1.3 (2) | 2.7 (10) | |
| Hypertension | 0.5 (1) | 0 | 0.3 (1) | |
| HIV | 0.5 (1) | 0 | 0.3 (1) |
Boldface indicates statistical significance:
P<0.05,
P<0.01,
P<0.001
ADHD, attention deficit hyperactivity disorder.
Motivations to use marijuana were separated into non-medical (e.g. fun, experiment) and medical purposes (e.g. sleep, pain), during adolescence and past 90 days (Table 3). During adolescents, top non-medical motivations, i.e. fun, experiment, were more frequently reported than top medical motivations, i.e. relax, sleep. No significant differences were found between patients and non-patients in any non-medical motivation domains (Table 3). Regarding medical motivations, patients were significantly more likely to report motivations pertaining to sleep, anxiety, depression and focusing (i.e. attention problems) than non-patients. During the past 90 days, top non-medical motivations were less frequently reported than top medical motivations. patients were significantly more likely to report one non-medical motivation – using marijuana to think differently – than non-patients. Patients were significantly more likely to report medical motivations concerning relaxation, sleep, anxiety, physical pain and focusing. Overall, significant differences between patients and non-patients’ motivations for marijuana use were consistently found in the medical domain during both adolescence and in the past 90 days.
Table 3.
Motivations for marijuana use during adolescence and past 90 days (N=366)
| Adolescence | Patients n=201 % (n) |
Non-Patients n=142 % (n) |
Total N=343a % (n) |
Unadjusted risk ratios (95%CI) |
|---|---|---|---|---|
| Non-medical motivations | ||||
| To have fun | 81.1 (163) | 76.1 (108) | 79.0 (271) | 1.1 (0.9–1.4) |
| To experiment | 75.1(151) | 72.5 (103) | 74.1(254) | 1.1 (0.9–1.3) |
| To celebrate | 63.7 (128) | 62.7 (89) | 63.3 (217) | 1.0 (0.8–1.2) |
| To help think differently or creatively | 63.2 (127) | 54.2 (77) | 59.5 (204) | 1.2 (1.0–1.4) |
| To relieve boredom | 49.8 (100) | 52.8 (75) | 51.0 (175) | 1.0 (0.8–1.1) |
| Medical motivations | ||||
| To help relax or feel more confident | 72.6 (146) | 65.5 (93) | 69.7 (239) | 1.2 (0.9–1.4) |
| To help sleep | 64.2 (129) | 51.4 (73) | 58.9 (202) | 1.3 (1.0–1.5)* |
| To relieve feeling anxious | 58.2 (117) | 44.4 (63) | 52.5 (180) | 1.3 (1.1–1.5)* |
| To relieve physical pain | 51.7 (104) | 42.3 (60) | 47.8 (164) | 1.2 (1.0–1.4) |
| To help me focus | 51.7 (104) | 35.9 (51) | 45.2 (155) | 1.3 (1.1–1.6)* |
| To cope with feeling depressed | 45.3 (91) | 31.0 (44) | 39.4 (135) | 1.3 (1.1–1.5)* |
| As a substitute for alcohol | 37.3 (75) | 32.4 (46) | 35.3 (121) | 1.1 (0.9–1.3) |
| Past 90 days | Patients n=210 % (n) | Non-patients n=156 % (n) | Total N=366 % (n) | Unadjusted risk ratios (95%CI) |
| Non-medical motivations | ||||
| To have fun | 68.6(144) | 71.8(112) | 69.9(256) | 0.9 (0.8–1.1) |
| To experiment | 20.0(42) | 17.9(28) | 19.1(70) | 1.1 (0.9–1.3) |
| To celebrate | 68.6(144) | 66.7(104) | 67.8(248) | 1.0 (0.9–1.3) |
| To help think differently or creatively | 75.2(158) | 62.2(97) | 69.7(255) | 1.3 (1.1–1.6)* |
| To relieve boredom | 47.6(100) | 46.2(72) | 47.0(172) | 1.0 (0.9–1.2) |
| Medical motivations | ||||
| To help relax or feel more confident | 87.6(184) | 78.2(122) | 83.6(306) | 1.4 (1.0–1.9)* |
| To help sleep | 82.9(174) | 72.4(113) | 78.4(287) | 1.3 (1.0–1.7)* |
| To relieve feeling anxious | 69.5(146) | 53.8(84) | 62.8(230) | 1.3 (1.1–1.7)* |
| To relieve physical pain | 71.4(150) | 53.8(84) | 63.9(234) | 1.4 (1.1–1.7)** |
| To help me focus | 64.3(135) | 48.7(76) | 57.7(211) | 1.3 (1.1–1.6)* |
| To cope with feeling depressed | 45.2(95) | 35.9(56) | 41.3(151) | 1.2 (1.0–1.4) |
| As a substitute for alcohol | 41.0(86) | 34.0(53) | 38.0(139) | 1.1 (1.0–1.4) |
Boldface indicates statistical significance:
P<0.05,
P<0.01,
P<0.001
Only participants who reported initiating marijuana use before the age of 19 (n=343) received the question about motivations for marijuana use during adolescence.
A majority of both patients and non-patients expressed some privacy concerns relating to the process of obtaining a medical marijuana recommendation (see Table 4). The possibility of a current or future employer finding out was the most common concern followed by their name being saved in a state database. Patients, who all possessed a doctor’s recommendation at the time of interview, were significantly less likely to report any privacy concerns and reported significantly fewer concerns than non-patients.
Table 4.
Privacy concerns relating to obtaining a doctor’s recommendation for medical marijuana (N=366)
| Variable | Patients n=210 % (n) |
Non-patients n=156 % (n) |
Total N=366 % (n) |
Unadjusted Risk Ratios (95%CI) |
|---|---|---|---|---|
| Any privacy concernsa | 63.3 (133) | 76.3 (119) | 68.9 (252) | 0.8 (0.7–0.9)* |
| Name saved in a state database associated with medical marijuana | 30.5 (64) | 48.1 (75) | 38.0 (139) | |
| Current/future employer finding out | 44.3 (93) | 65.4 (102) | 53.3 (195) | |
| Federal government finding out | 29.5 (62) | 41.0 (64) | 34.4 (126) | |
| Family finding out | 12.9 (27) | 24.4 (38) | 17.8 (65) | |
| Someone or something else finding out | 12.9 (27) | 19.9 (31) | 15.8 (58) | |
| Number of privacy concerns, mean (SD) | 1.3 (1.4) | 2.0 (1.6) | 1.6 (1.5) | t(364)= −0.7*** |
Boldface indicates statistical significance:
P<0.05,
P<0.01,
P<0.001
Includes five specified privacy concerns plus ‘other’ privacy concerns reported by 5 participants (4 patient and 1 non-patient).
Among patients only, the mean age of receiving a doctor’s recommendation for medical marijuana was 19.8 years old, which occurred approximately four to five years after the mean age of first episode of a primary health condition (14.9), non-medical marijuana initiation (15.1), or receiving a diagnosis for a primary health condition (15.6) (see Table 5). Furthermore, patients reported self-treating with marijuana at a mean age of 17.6 – approximately two years prior to receiving a medical marijuana recommendation. Psychological and pain problems were the most common primary health conditions reported to physician to receive a medical marijuana recommendation (Table 5). Approximately 85% or more of all recommendations that patients reported to a physician was reportedly a “genuine” health condition, with the most common being neurological and pain problems. Conversely, approximately 15% (n=26) of recommendations were based on a fabricated health problem. Among these, a majority (57.7%) indicated that access to marijuana for recreational purposes was the primary reason; one-third reported obtaining their recommendation as protection from arrest (data not shown in Table 5). Among patients reporting a genuine health condition to a physician, most had received a diagnosis for this condition by a physician (except for gastrointestinal conditions). Among patients ever indicating a psychological problem, 89.2% reported current marijuana use for this condition; among patients ever indicating a pain condition, 62.4% reported current use for this condition.
Table 5.
Primary health conditions, reason for marijuana use, and ages of initiation of key health events among young adult medical marijuana patients (n=210)
| Health Condition | Primary health condition for recommendation % (n) |
Primary health condition was genuine % (n) |
Ever diagnosed for primary health condition % (n) |
Reasons for current marijuana usea % (n) |
|---|---|---|---|---|
| Psychological | 53.8 (113/210) | 84.1 (95/113) | 63.2 (60/95) | 89.2 (166/186) |
| Pain | 35.2 (74/210) | 89.2 (66/74) | 68.2 (45/66) | 62.4 (111/178) |
| Gastrointestinal | 4.3 (9/210) | 88.9 (8/9) | 25.0 (2/8) | 40.9 (36/88) |
| Neurological | 2.4 (5/210) | 100 (5/5) | 80.0 (4/5) | 37.3 (19/51) |
| Drug/alcohol | 0 | 0 | 0 | 17.1 (6/35) |
| Other chronic medical conditions | 1.0 (2/210) | 100 (2/2) | 100 (2/2) | 9.1 (1/11) |
| Age | Mean (SD) | |||
| First episode of primary health condition (n=184)b | 14.9 (3.9) | |||
| First marijuana use (n=210) | 15.1 (2.3) | |||
| Diagnosis for primary health condition (n=119)c | 15.6 (3.9) | |||
| First self-treatment with marijuana (n=196)d | 17.6 (2.4) | |||
| Obtained doctor’s recommendation for medical marijuana (n=210) | 19.8 (2.2) | |||
Refer to Table 2 (lifetime prevalence of health conditions for patients) for denominator.
Only participants who reported a primary health condition received this question.
Only participants who reported receiving a diagnosis for a primary health condition received this question.
Only participants who reported self-treating with marijuana received this question.
Discussion
To our knowledge, this is the first detailed report on the physical and psychological health of young adult patients in the scientific literature. Overall, these results support the conclusion that young adult patients enrolled in this study reported health conditions and motivations for use that were consistent with medical use of marijuana under California law.
The primary types of problems ever experienced by young patients included psychological conditions (e.g. insomnia, anxiety, depression, ADHD), pain, nausea, and migraines. While these health problems are commonly found in the general population of adolescents and young adults [17,21], patients were more likely than non-patients to report them, suggesting higher prevalence among patients in the sample. Our results are in contrast to an US study comparing adult patients and non-patients, which found few differences in physical or psychological health between patients and non-patients [51]. Among young patients ever reporting one of these health problem, top reasons for current marijuana use were problems relating to psychological conditions and pain as well as gastrointestinal and neurological problems, which is consistent with the trend toward reporting using marijuana for psychological and pain conditions among older [5,9,12] and younger patients [13]. A small but notable subgroup reported using marijuana to treat reported drug or alcohol misuse, possibly using marijuana as substitute for these other substances [52–56].
Patients were more likely to report motivations for marijuana use as adolescents consistent with medical use (i.e. focusing, anxiety, depression) compared to non-patients. These results suggest that patients may have discovered some medical benefits for marijuana as non-patients [55] years before getting a medical marijuana recommendation, which was corroborated by patients reporting self-treatment with marijuana for health conditions approximately two years before obtaining a recommendation. In the past 90 days, patients were also more likely to report motivations aligned with medical use, e.g. anxiety, focusing, physical pain. Among patients, these results suggest a consistent trajectory of motivations for medical use linking periods before and after receiving a medical marijuana recommendation.
Consistent with their lifetime health histories, patients in this sample reported the types of health problems to a physician that would qualify them for a medical marijuana recommendation under California law [5]. Conditions relating to psychological problems and pain comprised nearly 90% of conditions reported to a physician. Over 85% reported that the health condition they indicated to a physician when obtaining a medical marijuana recommendation was genuine.
Notably, a group of patients reporting a fabricated health problem to a physician did so to obtain a recommendation as protection against arrest for marijuana possession, a legitimate concern given that approximately 10% of patients reported being arrested for marijuana. Drug-related convictions can substantially impact young adults’ future economic and educational opportunities [57,58]. While not part of the original intention of California’s medical marijuana law, reducing drug arrests among some young adult marijuana users may be an unintended effect of the law.
Findings indicate that a majority of patients also used marijuana for non-medical or recreational purposes [59,60]. Given that all patients initiated marijuana use prior to receiving a recommendation, use for recreational purposes is not surprising since marijuana use has historically been learned in the context of “pleasure” [61] with its medical applications discounted [62]. Patients who use for both medical and non-medical purposes, however, may present challenges to broader definitions and conceptions of what constitutes legitimate or appropriate use of marijuana.
Non-patients were found to be significantly less likely to have had psychological and physical health problems or report marijuana motivations aligned with medical use compared to patients. Non-patients, however, reported relatively high levels of physical and psychological problems overall [22, 38–42] as well as current motivations associated with medical use, e.g., pain, anxiety, or sleep. One-third reported using marijuana to cope with depression, some other problem, or as a substitute for alcohol. Hence, it is clear that non-patients in the sample had also experienced a range of health problems but to a lesser extent than patients. Their health conditions suggest that a proportion of non-patients might qualify for a medical marijuana recommendation in California. Related, non-patients expressed greater privacy concerns (e.g. name stored in a state database, family finding out) about obtaining a medical marijuana recommendation than patients [43]. These privacy concerns could partially explain why some non-patients – who might have had a qualifying physical and psychological condition – decided against obtaining a medical marijuana recommendation.
Demographically, there were no significant differences between patients and non-patients regarding age, gender, sexual identity, race/ethnicity, education or employment status, which suggests that young adult patients reflect the broader population of young adult non-patients along several key background characteristics. However, significant differences between patients and non-patients around concerns of drug testing and failing a drug test for marijuana use suggest that apprehensions linked to employment eligibility may be discourage some non-patients from seeking a medical marijuana recommendation. With 43.7% of young adult patients reporting Hispanic or Latino ethnicity, this is the first study of patients to capture more Hispanics than non-Hispanic whites, which also reflects the broader demographic features of Los Angeles with Hispanics approaching 50% of the city’s population.
Results from this analysis suggest that medical marijuana laws are reaching its intended target among young adults in Los Angeles since persons with histories of physical and psychological problems comprised the great majority of young adult patients. High proportions of non-patients reporting histories of physical and psychological problems suggest that some of these young adults may be eligible for a medical marijuana recommendation. Future studies should examine additional factors beyond privacy concerns, e.g. knowledge of program, cost of recommendations, cost of medical marijuana, that prevent young adults with medical conditions from obtaining a medical marijuana recommendation.
There are several limitations to this study. First, causal relationships cannot be determined due to the cross-sectional study design. Second, the sample was not randomly selected so the results may not be representative of all young patients and non-patients in Los Angeles. Related, a high proportion reported some college or above, which means that the sample is likely to over represent college-educated young adults. However, the sampling approach captured a largely diverse sample of young adult patients and non-patients that were closely matched along key demographic variables. Third, responses to interview questions are subject to recall bias and social desirability bias, particularly questions pertaining to whether the health condition reported to physician to obtain the recommendation was genuine or not.
Conclusions
A high proportion of young adult patients reported histories of physical and psychological problems and motivations for marijuana consistent with medical use. Patients were significantly more likely to report a range of health conditions and motivations associated with medical use than non-patients. While a great majority of patients appears to have obtained a medical marijuana recommendation for legitimate health problems, a notable proportion of non-patients also reported health problems that might qualify them for a medical marijuana recommendation under California law.
Acknowledgments
The authors would like to acknowledge the following individuals who supported the development of this manuscript: Miles McNeely, Meghan Treese, Ali Johnson, Chaka Dodson, Maral Shahinian, Avat Kioumarsi, Ekaterina Fedorova, and Megan Reed. Additionally, the authors would like to acknowledge the input and advice provided the study’s Community Advisory Board.
Role of Funding Source
Development of this manuscript was supported by grants from the National Institute on Drug Abuse (NIDA): DA034067 and DA034067-S1. NIDA had no role in the study design; collection, analysis, and interpretation of data; writing the manuscript; or decision to submit the manuscript for publication.
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