Prevalence of stimulant use in a sample of US medical students

Transcription

Prevalence of stimulant use in a sample of US medical students
ANNALS OF CLINICAL PSYCHIATRY
RESEARCH ARTICLE
ANNALS OF CLINICAL PSYCHIATRY 2013;25(1):27-32
Prevalence of stimulant use in a sample
of US medical students
Jadon R. Webb, MD, PhD
Yale Child Study Center
Yale School of Medicine
New Haven, CT, USA
Mark A. Valasek, MD, PhD
Department of Pathology
University of Texas Southwestern Medical
Center
Dallas, TX, USA
Carol S. North, MD
VA North Texas Health Care System
University of Texas Southwestern Medical
Center
Departments of Psychiatry and Surgery
Division of Emergency Medicine
Dallas, TX, USA
Stimulant use for academic performance is widespread
among college students, but less is known about use among students
obtaining advanced degrees.
BACKGROUND:
In this cross-sectional survey, we measured the prevalence
and demographic correlates of prescription stimulant use among a sample of US medical students.
METHODS:
The lifetime prevalence of stimulant use in this sample of 144
medical students was 20%, and prevalence of use during medical school
was 15%. More white students (32%) than Asian students (7%) had used
stimulants. Nine percent of respondents reported an attention-deficit/
hyperactivity disorder (ADHD) diagnosis, and those diagnosed were
more than 30 times more likely to have used stimulants compared with
those without a diagnosis. Of those who had taken stimulants, 83%
reported using them specifically for cognitive performance enhancement
such as studying better and staying awake longer while on clinical duties.
RESULTS:
This study suggests a high prevalence of stimulant use
among medical students compared with the general population. Personal
experience with these medications as medical students could impact physician attitudes and prescribing patterns toward patients seeking help for
ADHD-related symptoms.
CONCLUSIONS:
CORRESPONDENCE
Jadon R. Webb, MD, PhD
Yale Child Study Center
230 South Frontage Road
New Haven, CT 06519 USA
KEYWORDS: attention-deficit/hyperactivity disorder, stimulants, students
INTRODUCTION
E-MAIL
jadon.webb@yale.edu
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Many high school and college students report using prescription stimu-
Annals of Clinical Psychiatry | Vol. 25 No. 1 | February 2013
27
MEDICAL STUDENT STIMULANT USE
lant medications in an attempt to boost their cognitive
performance.1 These students state that stimulants help
them stay awake longer, study with better focus, and perform better on exams.1-6 Experimental studies of these
drugs show that, although we have much still to learn,
there may be some truth to these beliefs (as previously
described by Webb et al7). The cognitive benefits of stimulants might be thought to lead to their illicit use in more
demanding academic environments, and indeed, use by
students is more prevalent at highly competitive schools
and during times of increased academic stress.3,6,8
Medical school is a challenging environment characterized by large volumes of study material, late nights
studying, and competitive classmates. As such, it is a
prime setting to examine the prevalence of stimulant
use, especially use intended for performance enhancement. Relatively high prevalence of stimulant use was
noted in other professional school environments, for
example among dental9 and pharmacy4 students. Few
studies have examined medical student stimulant use,10
compared with the many studies among high school
and college populations.1 Medical students eventually
will become the prescribing doctors who dispense these
medications, and their personal experience with stimulant use may affect future prescribing trends for children
diagnosed with attention-deficit/hyperactivity disorder
(ADHD) and students experiencing academic difficulties
for other reasons.
In this report, we examine the prevalence and demographic characteristics of stimulant use among third-year
medical students at 1 school in the United States. We
additionally asked how these medications were obtained,
the intended use for the medication, and what students
believe about the effectiveness of using stimulants as performance enhancers.
METHODS
Survey
After obtaining university institutional review board
approval, an anonymous, confidential, paper-and-pencil survey consisting of 16 multiple-choice and free-form
questions was administered to third-year medical students prior to orientation lectures at a southern US medical school (complete survey is available as an APPENDIX).
The response rate was 98%, with 145 total responses
among 148 students in the third year of medical school.
28
Stimulant use
Students were asked the following survey items to
assess stimulant use: “Over your entire lifetime, have
you ever used a stimulant medication?” and “While in
medical school, have you ever used stimulant medication for any reason?” Stimulants were defined in the
survey as those typically prescribed for ADHD, such as
methylphenidate, dexmethylphenidate, amphetamine
salts, dextroamphetamine, benzphetamine, lisdexamfetamine, and other medications used to treat ADHD or
sleep disorders including atomoxetine and modafinil.
Caffeine was excluded from the definition of stimulants in the survey. Students were asked to identify
which stimulant(s) they had used, and specify whether
these stimulants were prescribed to them. They also
were queried on whether they were offered stimulants
other than by prescription while in medical school,
and whether they used these medications specifically
to improve academic performance. Participants could
choose reasons that they used stimulants, including to
stay awake longer, focus while studying, perform better
on exams, perform better on clinical ward duties, and
lose weight.
Student perceptions
Several questions on the survey addressed medical students’ beliefs regarding stimulant use. For example,
students were asked: “Do you believe that stimulants or
related medications can help improve academic performance (eg, grades or clinical performance)?” and “What
percentage of your class do you believe uses stimulants to
improve their academic performance?”
Data analysis
Prevalence of stimulant use was calculated by dividing the number of students reporting a behavior by
the total number of responses to that question.
Bivariate associations between student characteristics and stimulant use questions were tested with the
Fisher exact test for dichotomous and categorical
outcomes. Unadjusted odds ratio (OR) and 95% confidence intervals are reported. Two-tailed statistical
significance is defined as P ≤ .05. Numerical averages
are reported as mean ± standard error. All statistical analyses were performed with Microsoft Excel or
Web-based calculation from http://faculty.vassar.edu/
lowry/odds2x2.html and http://www.graphpad.com/
quickcalcs/ttest2.cfm.
February 2013 | Vol. 25 No. 1 | Annals of Clinical Psychiatry
ANNALS OF CLINICAL PSYCHIATRY
TABLE 1
Prevalence of stimulant use by student demographics
Total sample (n)
Lifetime use (%)
OR (95% CI)
Medical school use (%)
OR (95% CI)
144
20%
–
15%
–
Male
73
26%
2.2 (0.9 to 5.0)
21%
2.8 (1.0 to 7.7)
Female
71
14%
–
8%
–
<26
98
19%
–
13%
–
≥26
45
22%
1.2 (0.5 to 2.8)
18%
1.4 (0.5 to 3.7)
Asian
54
7%
a
4%
a
White
60
32%
5.8 (1.8 to 18.4)b
25%
8.7 (1.9 to 40.0)b
Hispanic
17
24%
3.9 (0.9 to 17.5)
18%
5.6 (0.9 to 36.7)
Black
7
14%
2.1 (0.2 to 21.8)
0
–
Married
27
11%
–
7%
–
Not married
115
23%
2.3 (0.7 to 8.4)
17%
2.5 (0.5 to 11.3)
<240
84
19%
–
14%
–
≥240
49
22%
1.2 (0.5 to 2.9)
16%
1.2 (0.4 to 3.1)
Yes
13
85%
34.5 (7.1 to 168.7)b
77%
37.3 (8.9 to 155.8)b
No
131
14%
–
8%
–
Total
Sex
Age
Race
Marital status
Gradesc
ADHD diagnosis
comparison of races was a series of bivariate analyses comparing all others to Asians, who had the lowest use prevalence.
a
corrected statistical significance, P < .003.
b
United States Medical Licensing Examination Step 1 scores.
c
ADHD: attention-deficit/hyperactivity disorder; OR: odds ratio.
R E S U LT S
Student respondent demographics
The final respondent sample was 50% women, with a
mean age of 25 ± 0.2 years. Whites comprised the largest proportion of respondents at 41%, followed by Asian
(37%), Hispanic (12%), black (5%), and other (1%).
Nineteen percent of respondents were married, and 9%
of respondents reported a lifetime diagnosis of ADHD.
The most commonly reported United States Medical
Licensing Examination (USMLE) Step 1 scores (standardized measures of academic success) were in the 220
to 240 range, which is slightly above the national average.
Stimulant use
As shown in TABLE 1, 20% of students reported lifetime use
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of stimulants, with 15% using stimulants while in medical
school. Prevalence of stimulant use differed as a function
of student characteristics, with white students having a
more than 9-fold odds for use compared with Asians during medical school (P = .001). Thirteen students (9% of the
sample) reported a diagnosis of ADHD, and they showed
an OR of 37 for stimulant use in medical school relative to
those without an ADHD diagnosis (P < .001). Some earlier
studies have suggested that males are more likely to use
stimulants.8 A higher proportion of males reported use
on our sample; however, this result was not significant (P
= .10). There were no significant differences in prevalence
as a function of age, marital status, or scholastic status
(USMLE scores). Indeed, those with high standardized test
scores had an almost identical use prevalence compared
with those with lower test scores (TABLE 1).
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MEDICAL STUDENT STIMULANT USE
TABLE 2
Motivations for stimulant use by medical
students reporting any stimulant use
Motive (n = 60)
No. (%) of users
Focus while studying
24 (83%)
Stay awake
13 (45%)
Perform better on exams
11 (38%)
Perform better on clinical duties
9 (31%)
Lose weight
3 (10%)
Numbers do not add to 100% because respondents were able to choose
>1 category.
Of those with lifetime stimulant use histories during medical school, most (52%) obtained at least some
stimulants without a prescription (not shown in TABLE 1).
Additionally, 25% of students surveyed reported that they
had been offered these medications without prescription
while in medical school.
Most of those who reported using stimulants (24
of 29 people, 83%) reported using them specifically to
improve cognitive performance, and the prevalence of
specific reasons is shown in TABLE 2. Those who used
stimulants often reported using either methylphenidate (52%, TABLE 3) or amphetamine salts (52%). Fewer
reported using lisdexamfetamine, atomoxetine, dexmethylphenidate, or modafinil.
Perceptions of stimulant use
A majority of medical students (73%) reported that they
believe stimulants can help improve cognitive performance, and this perception was shared between those
who had ever used stimulants (86% agreeing with this
statement), and those who had not (69% agreeing, P =
.10). Students also were asked to estimate the prevalence
of stimulant use among their peers, and gave an average
estimate of 0.27 ± 0.02, which was not significantly different than the actual observed lifetime average of 0.20 ±
0.03 (P = .053). Students who reported having used stimulants also reported a significantly higher estimation of
use among their peers (0.36 ± .04) compared with those
who had not used (0.24 ± .02, P = .008).
DISCUSSION
The primary objective in conducting this research was to
assess the prevalence of stimulant use among students
30
at a medical school in the southern United States. The
approximately 20% lifetime use prevalence observed in
this study is higher than in a prior study of medical students (lifetime use 10.1%).10 It also is distinctly higher
than the average prevalence among college students
(6.9%), although a few outlying schools reported prevalence closer to the higher range in our study.8 As hypothesized, the prevalence of stimulant use appears to be
relatively high among medical students.
Stimulant use has been previously noted to vary considerably by respondent demographics.11 In our sample,
white medical students were more likely to have used
stimulants compared with Asians, who were the largest
minority student population and had the lowest reported
prevalence of any racial group. The sample size was not
large enough to reliably compare prevalence among
black and Hispanic medical students, although prior
studies of college students suggests that whites have the
highest prevalence of use of any group.12 In college populations, males appear to be at increased odds of using
stimulants,8,12 although some studies have not observed
this difference.13 In our survey, we were not able to detect
a significant difference in use between sexes, although
the finding of a nonsignificant trend favoring use by
males may deserve further scrutiny in a larger study to
clarify whether a sex difference exists in stimulant use
among medical students.
In contrast to earlier work14,15 that has characterized
stimulant users as being academically troubled, we did
not find an association between standardized grades and
prevalence of use. Indeed, we noted that students who
achieved very high standardized test scores reported
nearly identical rates of stimulant use as those with
lower scores. It is known that stimulant users in college
are more likely to abuse other illegal drugs,15,16 and may
represent an at-risk population that generally is more
prone to deviance and academic failure. Further study is
needed to examine whether a similar trend in drug use
and deviance occurs among medical students. Based
on the lack of association with grades in our sample, we
speculate that perhaps a significant portion of medical
students are more utilitarian in their drug use, and specifically seek out stimulants as a study tool while avoiding
other drugs and deviant behaviors that may impair their
academic performance.
A potential confounding issue regarding stimulants
and academic performance is the diagnosis of ADHD.
A higher proportion of medical students (9%) reported
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ANNALS OF CLINICAL PSYCHIATRY
having been diagnosed with ADHD, compared with
4.4% in a recent survey of the general adult population,17
and a prior report of 5.5% prevalence among medical
students at a different institution.10 As expected, students reporting an ADHD diagnosis were far more likely
to have used stimulants than their peers. The majority
of these users reported specifically using stimulants as a
means of performance enhancement; however, it is possible that students with ADHD may interpret the question of performance enhancement as a way of coping
with cognitive deficiencies arising from their medical
condition. Because the reported prevalence of ADHD in
these medical students is higher than that of the general population, there also is the question of whether
some of these students sought out a diagnosis as a legal
means of obtaining stimulants. It would be of interest
in future work to closely examine how the diagnosis of
ADHD was obtained, and to what degree students feel
that they are medicating for a deficiency vs use for academic enhancement.
Diversion is common among college students prescribed stimulants, with approximately 1 in 3 students
selling or giving the medication to someone else.18
Although we did not directly address the issue of selling
or sharing stimulants obtained by prescription by the
students in this study, it is notable that 25% of students
reported being offered stimulants other than by prescription while in medical school, and the majority of users
reported obtaining at least some of these medications
other than by prescription. This suggests that diversion
is widespread even at this academic level, just as it is in
college. Students seemed aware of how widespread such
use is, and accurately guessed that about 1 in 4 of their
classmates were using stimulants.
This study had a very high response rate (98%). As
such, this sample represented the entire third-year medical student body currently attending this particular medical school. Limitations of this study include a sample size
that did not provide sufficient power to permit subgroup
analyses, and that it was conducted at a single institution;
therefore, it could not address several secondary hypotheses of interest, and the findings may not generalize to
other medical schools in other parts of the country. It also
did not include resident and attending physicians in the
sample, which would be of interest when considering use
trends as training progresses. Although honest reporting
in any survey is a concern, the surveys were anonymous,
and the prevalence reported from this survey is in line
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TABLE 3
Specific prescription stimulants used by
medical students reporting use of any stimulant
Medication
No. (%) of users
Methylphenidate
15 (52%)
Dextroamphetamine
15 (52%)
Lisdexamfetamine
2 (7%)
Atomoxetine
2 (7%)
Dexmethylphenidate
2 (7%)
Modafinil
1 (3%)
with or higher than prior studies, suggesting that the data
are likely at least comparable to prior work surveying
stimulant use.
CONCLUSIONS
Medical training is a demanding endeavor; students
often are pushed to the limits to succeed, and must find
ways of coping and adapting. Three-fourths of medical
students reported that they believed stimulants could
enhance cognitive performance, and 1 in 5 had used
them, typically for performance enhancement. This has
implications for medical training facilities, because they
must grapple with teaching high volumes of material to
students while attempting to minimize adverse effects
on student health and wellbeing. It also has implications for patient care, because medical students who use
stimulant medications or who work with colleagues who
use them may be influenced by these experiences when
treating patients reporting ADHD symptoms. ■
Drs. Webb and Valasek report no financial relationship with any company whose products are
mentioned in this article or with manufacturers of competing products. Dr. North receives grant or research
support from the American Psychiatric Association, the
National Institute of Diabetes and Digestive and Kidney
Diseases, the National Institute on Alcohol Abuse and
Alcoholism, the Orthopaedic Trauma Association, and
the US Department of Veterans Affairs; is a consultant to
the Tarrant County (TX) Department of Health and the
University of Oklahoma Health Sciences Center; and is a
speaker for the Pueblo City/County (CO) Department of
Health.
DISCLOSURES:
Annals of Clinical Psychiatry | Vol. 25 No. 1 | February 2013
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MEDICAL STUDENT STIMULANT USE
APPENDIX
Complete survey of stimulant use among medical students
1. Sex
__ Male
__ Female
2. Age ___
3. Race
__ White
__ African-American
__ Hispanic
__ Asian
__ Other (please specify):
____________________________
4. Marital status
__ Married__ Divorced/separated
__ Never married
6. Approximate USMLE Step 1 score:
<200 _______220-240: _______
200-220: _______
>240: _______
7.Have you ever been diagnosed with attention deficit disorder
(ADD) or attention-deficit/hyperactivity disorder (ADHD)?
__ Yes
__ No
8. Over your entire lifetime, have you ever used a stimulant
medication? Stimulant medications are those typically
prescribed for ADD/ADHD, such as Ritalin, Adderall, Concerta,
Vyvanse, and Dexedrine (excluding caffeine).
__ Yes
__ No
9. While in medical school, have you ever used stimulant
medication for any reason? (excluding caffeine)
__ Yes
__ No
10.If yes, have you used stimulants or related medications
specifically to improve academic performance (eg, to study
better or perform better on ward duties)?
__ Yes
__ No
11. Which of these specific reasons have you used stimulants or related
medications for? (please check all that apply, excluding caffeine)
__ To stay awake longer
__ To focus while studying
__ To perform better during exams
__ To perform better (stay awake, be more alert) on clinical
ward duties
__ To lose weight
12. Which stimulants or related medications did you use while in
medical school? (please check all that apply)
__ methylphenidate (eg, Ritalin, Concerta, Metadate, Daytrana, etc.)
__ atomoxetine (eg, Strattera)
__ dexmethylphenidate (eg, Focalin)
__ amphetamine/dextroamphetamine (eg, Adderall)
__ dextroamphetamine (eg, Dexedrine, etc.)
__ benzphetamine (eg, Didrex)
__ lisdexamfetamine (Vyvanse)
__ modafinil (eg, Provigil, Alertec)
__ other (please specify): _________________________________
13. Was this stimulant medication specifically prescribed to you?
__ Yes
__ No
14. Do you believe that stimulants or related medications can
help improve academic performance (eg, grades or clinical
performance)?
__ Yes
__ No
15. Have you ever been offered stimulants or related medications
(other than by prescription) while in medical school?
__ Yes
__ No
16. What percentage of your class do you believe uses stimulants to
improve their academic performance?
_____%
17. How healthy do you consider yourself to be?
__ 5-excellent health
__ 2-fair health
__ 4-very good health
__ 1-poor health
__ 3-good health
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