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 AACP.com 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 AACP.com 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). Annals of Clinical Psychiatry | Vol. 25 No. 1 | February 2013 29 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 February 2013 | Vol. 25 No. 1 | Annals of Clinical Psychiatry 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 AACP.com 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 31 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 REFERENCES 1. Wilens TE, Adler LA, Adams J, et al. Misuse and diversion of stimulants prescribed for ADHD: a systematic review of the literature. J Am Acad Child Adolesc Psychiatry. 2008;47:21-31. 2. Carroll BC, McLaughlin TJ, Blake DR. Patterns and knowledge of nonmedical use of stimulants among college students. Arch Pediatr Adolesc Med. 2006;160:481-485. 3. DeSantis A, Noar SM, Webb EM. Speeding through the frat house: a qualitative exploration of nonmedical ADHD stimulant use in fraternities. J Drug Educ. 2010;40:157-171. 4. Lord S, Downs G, Furtaw P, et al. 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