Neuro-enhancement among German junior physicians: Prevalence,reasons and associations to mental health outcomes and quality of life

Abstract

BACKGROUND:

Previous research studies have demonstrated that neuro-enhancement, the use of legal or illegal drugs by healthy individuals to improve their job performance, is practiced among employees. Researchers discussed possible reasons for employees to consider the use of substances for neuro-enhancement.

OBJECTIVE:

The aim of this study was to identify the prevalence of usage and motives for practicing neuro-enhancement among a sample of German junior physicians. The secondary objective was to determine associations between neuro-enhancement, mental health outcomes and quality of life.

METHODS:

This cross-sectional study included an online survey to analyze junior physicians’ neuro-enhancement stimulant use and their motives for usage (n = 873). Second, mental health outcomes and quality of life were assessed. Descriptive and analytic (Kruskal Wallis test, logistic regression) statistics were obtained.

RESULTS:

Of the 873 junior physicians, 18% reported having used stimulants for neuro- enhancement. 8% of the physicians have taken prescription stimulants (e.g. modafinil) or illicit drugs (e.g. cannabis) at least once in their lifetime. The most common reasons for taking stimulants were to enhance concentration, to relax and to increase alertness. Neuro-enhancement was associated with emotional exhaustion (p < 0.01), lower quality of life (p < 0.05) and work-related stress (p < 0.01).

CONCLUSIONS:

Our study results give an overview on the actual situation regarding frequency and motives for taking performance-enhancing substances. The prevalence rate was low in comparison to current public debates. Decreasing the prevalence of neuro-enhancement among physicians requires the implementation of strategies targeting stress reduction and workload management.

Keywords

Drugs performance enhancement motives stress management quality of life

1 Background

Neuro-enhancement is defined as the amplification or extension of core capacities of the mind through improvement or augmentation of internal or external information-processing systems [1]. According to this definition, a cognitively enhanced person is somebody who has benefited from an intervention that improves his/her cognitive performance without correcting a specific pathology or dysfunction of that sub-system [1].

Neuro-enhancing substances can be grouped in prescription stimulants, illicit drugs and phyto-chemicals. Prescription stimulants include, e.g. amp-hetamines such as methylphenidate (brand names: Ritalin, Concerta, Metadate, or Methylin) or Adderall [2, 3].

Studies demonstrated effects of methylphenidate: it improves accuracy in complex working memory tasks in normal individuals [2]. Modafinil (brand names: Provigil, Alertec, Modavigil, Modalert) is another stimulant. Modafinil increases executive functions and performance. It is usually used to treat narcolepsy and other sleep disorders [2]. Modafinil has been demonstrated to reduce deficits in cognitive performance during night-shift work and under sleep deprivation [4 –6].

Phytochemicals (e.g. valerian, ginkgo biloba, St. John’s Wort) are derived from plants and can modify the functioning of the central nervous system. Many of these phytochemicals can be grouped by the chemical nature of their potentially active sec-ondary metabolite constituents into alkaloids (caffeine, nicotine), terpenes (ginkgo, ginseng, valerian), and phenolic compounds (curcumin). The most frequently used substances to enhance performance are caffeine and energy drinks [7, 8]. In addition, studies illustrated that cannabis and marijuana have been used to relax.

Illicit drugs are illegal to process, sell, and consume. These include e.g. cocaine, methamphetamine, and heroin. Illicit drugs playing a role in enhancing performance, i.e. β-blockers, cocaine [9].

1.1 Prevalence of non-medical use of prescription stimulants among employees

The non-medical use of prescription stimulants (such as methylphenidate) by employees has recently drawn attention. Previous study findings of representative survey studies demonstrated that 6.7% –8.3% of German employees take stimulants to enhance job performance. A study performed by the Federal Institute for Occupational Safety and Health (BAuA) demonstrated a lifetime prevalence rate of 8.30% among German employees [10]. Studies on prevalence rates focusing physicians are rare. A study by Franke et al. demonstrated a lifetime prevalence rate of 8.9% [5].

1.2 Reasons for taking non-medical use of prescription stimulants among employees

Researcher discussed possible reasons for employees to consider the use of substances for neuro-enhancement. Related issues were to maximize per-formance, pressure by the employer, and improving well-being [2, 5].

Previous studies demonstrated that improving concentration was the main reason for employees to take neuro–enhancing substances (e.g. stimulants or drugs) [11]. A second reason was for increasing the focus for a specific task and memory capacity; and another study showed that creativity was reason mentioned by employees [12].

Previous research indicated that working as a junior physician in a hospital is characterized by high levels of working hours, high patient loads and demanding job tasks [13 –17]. Hospital physicians are often exposed to an excessive workload leading to mental and physical exhaustion, e.g. sleep deprivation [18 –20]. In order to maintain high cognitive performance, physicians may come under pressure to counteract fatigue, distress, concentration deficits, or symptoms of depression by the use of cognitive enhancing substances.

To date, scientific evidence is missing, especially among physicians that prove these motives lead to the consumption or prescription of illicit drugs during work. Some researcher discuss neuro enhancement as a form of coping strategy that is time-saving, effective and an easy alternative than more time-consuming coping strategies (sleep, relaxation techniques, etc.) [5].

There has been speculation as to which other medical specialties are at “high risk” for neuro-enhancement. Prior research in addiction discuss that anesthesiologists, physicians in Emergency Medicine, and psychiatrists are supposed to be particularly troubled [21 –23].

Several studies have investigated the prevalence and reasons for taking neuro–enhancing substances in different work settings and/or countries. In this respect, the prevalence of neuro-enhancement among junior physicians with high workload, shift work, and further demanding working conditions, has not yet been assessed in detail.

To our knowledge, only few studies have analyzed the usage, motives and gender effects for taking neuro-enhancing stimulants by doctors in general. There is no study on frequency and motives among German physicians working different medical disciplines for taking neuro-enhancing substances.

Therefore the aim of this study was to give an overview on (1) how many German hospital junior physicians have taken neuro-enhancing substances, (2) what kind of substances have been used, (3) what motives and reasons for using exist and (4) which factors can be found that may influence neuro-enhancing behavior.

2 Methods

2.1 Ethics

Ethical approval was granted by the Medical Association, Hamburg. Ethical approval was obtained from the Institutional Review Board of the Charité Universitätsmedizin Berlin. The study is in accordance with the Helsinki Declaration of 1964. In-formed consent was obtained from all participating physicians included in this study.

2.2 Study design and study sample

This cross-sectional survey study was conducted between December 2017 and October 2018. A total of 2425 hospital physicians working in different medical fields were recruited via email to take part in this study. In total 873 physicians participated (response rate 36%). A consent form was placed at the beginning of the online survey (including information on what the study is about voluntary participation, risks, confidentiality/anonymity, right to withdraw). Whilst participants are not signing a separate consent form, consent is obtained by virtue of completion with participants selecting an “I agree” button to continue. Participation in the study was voluntary and anonymous, and the participants faced no temporal restrictions in completing the survey.

Inclusion criteria were: full-time work contract and working experience of max. 5 years (study aim was to focus on junior physicians). Participants with self-reported psychiatric disorders (e.g. attention deficit/hyperactivity disorder) were excluded as these employees are likely to use prescribed stimulants. Due to the use of this methodological approach, an exact response rate could not be determined.

2.3 Study measures

The survey included information on demographics (age, gender, and relationship status), hours worked per week and nights on call. In addition, the questionnaire contained items about the nonmedical use of stimulants with the particular intention of neuro-enhancement.

The following items pertained to the participants’ use of several neuro-enhancers during work. Prescription drugs included amphetamines, antidepressants (SSRIs), antidementia drugs, and selective beta blockers, and/or the use of illegal drugs, to improve cognitive performance or mood.

Other substances with psychotropic properties were not covered. The survey involved generic and brand names in order to increase clarity for participating physicians. An overview of all substances included in this study is shown in Table 1.

Table 1
Neuro-enhancement prevalence rates among German physicians (n = 873)

Use of substance Never used Within the last 12 months Within the last month Within the last week Once per day Several times a day

n (%) n (%) n (%) n (%) n (%) n (%)

Non-prescription stimulants

Caffeinated beverages 192 (22) 64 (7.3) 32 (3.7) 93 (10.7) 201 (23) 291 (33.3)

Caffeine tablets 789 (90.4) 58 (6.6) 12 (1.4) 9 (1.0) 4 (0.5) 1 (0.1)

Cigarettes 639 (73.2) 62 (7.1) 13 (1.5) 40 (4.6) 20 (2.3) 99 (11.3)

Hashish/marijuana 754 (86.4) 81 (9.3) 19 (2.2) 14 (1.6) 4 (0.5) 1 (0.1)

Phytochemicals 689 (78.9) 128 (14.7) 27 (3.1) 15 (1.7) 11 (1.3) 3 (0.3)

Prescription stimulants

Modafinil (i.e. Vigil) 867 (99.3) 4 (0.5) 2 (0.2) – – –

Amphetamine (i.e. Adderall) 863 (98.9) 8 (0.9) 2 (0.2) – – –

Methylphenidat (i.e. Ritalin) 865 (99.1) 6 (0.7) 1 (0.1) 1 (0.1) – –

Beta Blocker 855 (97.9) 11 (1.3) 1 (0.1) 6 (0.7) – –

Illicit drugs

Ecstasy 848 (97.2) 14 (1.6) 1 (0.2) – – –

Cocaine 854 (97.8) 16 (1.8) 3 (0.3) – – –

Use of substance	Never used	Within the last 12 months	Within the last month	Within the last week	Once per day	Several times a day
Non-prescription stimulants
Caffeinated beverages	192 (22)	64 (7.3)	32 (3.7)	93 (10.7)	201 (23)	291 (33.3)
Caffeine tablets	789 (90.4)	58 (6.6)	12 (1.4)	9 (1.0)	4 (0.5)	1 (0.1)
Cigarettes	639 (73.2)	62 (7.1)	13 (1.5)	40 (4.6)	20 (2.3)	99 (11.3)
Hashish/marijuana	754 (86.4)	81 (9.3)	19 (2.2)	14 (1.6)	4 (0.5)	1 (0.1)
Phytochemicals	689 (78.9)	128 (14.7)	27 (3.1)	15 (1.7)	11 (1.3)	3 (0.3)
Prescription stimulants
Modafinil (i.e. Vigil)	867 (99.3)	4 (0.5)	2 (0.2)	–	–	–
Amphetamine (i.e. Adderall)	863 (98.9)	8 (0.9)	2 (0.2)	–	–	–
Methylphenidat (i.e. Ritalin)	865 (99.1)	6 (0.7)	1 (0.1)	1 (0.1)	–	–
Beta Blocker	855 (97.9)	11 (1.3)	1 (0.1)	6 (0.7)	–	–
Illicit drugs
Ecstasy	848 (97.2)	14 (1.6)	1 (0.2)	–	–	–
Cocaine	854 (97.8)	16 (1.8)	3 (0.3)	–	–	–

To calculate frequency of use of prescription drugs and use of illicit substances, physicians were asked to indicate the frequency with which they used the substances (e.g. never, within the last 12 months, within the last month, within the last week, once per day, several times a day). Further items contained questions regarding the use of other non-prescription substances influencing performance or mood. We included items regarding the usage of caffeine tablets, cannabis, and various phytochemicals (e.g. valerian, ginkgo biloba, St. John’s Wort). Response options included: never, within the last 12 months, within the last month, within the last week, once per day, several times a day.

Moreover, reasons and motives for taking cognitive enhancing stimulants were analyzed. Reasons were: to improve performance, improve concentration, increase alertness and vigilance, relaxation, fear of disadvantages compared with drug users, manage the pressure to succeed, fun etc.. Respondents could select more than one reason (multiple-response questions).In addition, symptoms of burnout, depression, work family conflict and quality of life were measured.

2.4 Work-related stress

We included the work-related stress scale developed by Enzmann and Kleiber in 1989. The scale consists of six items, such as “I often feel overburdened.” Responses ranged from 1 = “not applicable at all” to 5 = “completely applicable”[24]. Results showed good internal consistency of this measure (Cronbach’s α: 0.83).

2.5 Burnout

The Maslach Burnout Inventory (MBI), a validated 22-item questionnaire, was used for measuring burnout [25]. The MBI offers a sum score for each domain of burnout: emotional exhaustion, depersonalization, and personal accomplishment.

2.6 Work-family conflict (WFC)

WFC was measured by using the German version of the original instrument by Netemeyer [26]. This instrument consists of five items including questions on the influence of work on personal or family life, to be answered with a five-point Likert scale (from ‘strongly agree’ to ‘strongly disagree’). The internal consistency of the scale with our sample was good (α= 0.82).

2.7 Satisfaction with life/quality of life

Satisfaction with life was measured with the German version of the Satisfaction with Life Scale (SWLS) [27]. Items are answered on a 5-point rating scale. Internal consistency of the scale was satisfactory (α= 0.79). Finally, the survey included questions regarding socio-demographics (e.g. age, gender, medical discipline, and years of working experience).

Reliability, validity and applicability of the ques-tionnaire were confirmed. Cronbach’s alpha coefficients for the items were higher than Cronbach’s Alpha≥0.70 and all inter-correlations were measured between r = 0.60 and r = 0.80.

2.8 Statistical analysis

Descriptive statistics were analyzed to characterize the physician samples. Associations between variables were evaluated using the Kruskal-Wallis test (continuous variables) or chi-square test (categorical variables) as appropriate. All tests were 2-sided with type I error rates of 0.05. Multivariate analysis of differences across physicians’ specialties were performed using logistic regression. Similarly, a multivariate logistic regression analysis of physicians was performed to identify demographic and professional characteristics associated with the dependent outcomes.

Frequency distributions of participants’ demographic characteristics and their motives for using neuro-enhancers were determined and rates of use were calculated. The correlations between the participants’ use of neuro-enhancers were determined by performing a series of correlation analyses. All analyses were performed using SPSS for Windows Version 23.

3 Results

3.1 Study participants

A total of 56% female participants (n = 489) were included in the study. The average age±standard deviation (SD) of the total sample was 30 years (SD = 2.5).

Working experience was M = 2.5 years (±SD = 1.4 years). Distribution of medical disciplines is illustrated in Fig. 1.

Fig. 1

Lifetime prevalence of prescription and illicit stimulants among medical specialties.

The mean weekly workload was estimated to be 45.6 hours (SD = 9.0 h). We analyzed early res-ponders versus late responders. No statistically significant differences with respect to age, gender, or specialty were identified.

3.2 Frequency of stimulant-use

Table 1 shows data for the overall study sample, stratified by stimulant-use status: non-medical use of prescription stimulants or illicit drug use other than non-medical use of prescription stimulants (including marijuana, cocaine, methylphenidate, amphetamines etc.).

3.2.1 Use of prescription stimulants or illicit drugs

A total amount of 8.7% of the physicians (n = 76) reported having used a prescription stimulants or illicit drugs for performance enhancement at least once during their lifetime.

Taking methylphenidate products have been reported by 0.9% of cognitive stimulant users, whereas 0.7% have used modafinil at least once in their lifetime. An amount 1.1% of physicians did admit the use of amphetamines. The longer physicians practiced the less likely they reported use of prescription stimulants (p < 0.001). A similar association occurred with working hours (p < 0.001), while more hours resulted in the higher the prevalence of usage. No significant differences in frequency of consumption could be found for the variable working experience (p > 0.05).

Gender, age and family status showed no significant associations with the presence of prescription stimulant use.

Figure 1 represents the stratification of prescription stimulants by medical specialty. The difference in prevalence of prescription stimulants or illicit drugs among the various specialties was statistically significant (p < 0.05) with the highest lifetime prevalence among surgeons (9.2%) and the lowest prevalence among pediatricians (7.5%).

3.2.2 Use of phytochemicals

Regarding the use of caffeine, 78% (n = 681) of all participants reported consuming caffeine by ingestion of caffeinated beverages (e.g., coffee, energy drinks) while 9.6% (n = 84) reported consuming caffeine by intake of caffeine tablets. No significant gender differences could be found consuming caffeine by ingestion of caffeinated beverages (P > 0.05).

13.6% of the participants (n = 119) reported using hashish/marijuana. The subgroup analysis showed a greater proportion was male (χ² = 19.07, p < 0.05).

21% of the physicians (n = 183) reported using other phytochemicals (e.g., valerian, ginkgo biloba, or St. John's Wort); a much greater proportion was female (χ² = 18.19, P < 0.001). Use was more likely in those who were younger (p < 0.0001) and partnered (p < 0.0001).

3.2.3 Motives for neuro-enhancement

The participants reported that their leading motives for using cognitive stimulants were to improve performance (41%), concentration (38%), increase vigilance (41%), enhance cognitive potential (29%), and cope with stress (39%). No significant differences between gender were observed regarding any motives.

3.2.4 Assessment of positive and negative effects of neuro-enhancement

Focusing on positive effects of neuro-enhancement, 36% (n = 314) of all physicians reported that they believe that neuro-enhancers such as prescription stimulants have a performance-improving effect. 39.8% (n = 348) believe that the use is associated with psychological addiction.

With regard to differences between physicians who were taking cognitive enhancers at the time of the study and those who were not, the former subgroup was less likely to believe that practicing neuro-enhancement would have health consequences (P < 0.05). In addition, the user group stated that it would improve cognitive (P < 0.001) and relaxation effects (P < 0.001) compared to the non-user group.

3.2.5 Multivariate analysis of factors associated with the use of prescription and illicit drugs for neuro-enhancement

We also analyzed the relationship between use of prescription stimulants (i.e. Modafinil, see Table 1) and illicit drugs (Cocaine and Ecstasy) for neuro-enhancement and work-related stress, burnout and quality of life. Burnout was more frequent in physicians using prescription stimulants or illicit drugs (p < 0.001). Physicians who screened high for work-related stress were more likely to use neuro-enhancers (p < 0.001).

Use of prescription stimulants and illicit drugs was associated with lower overall quality of life (p < 0.001). Mental (p < 0.035), physical (p < 0.01), and emotional (p < 0.01) quality of life were lower in physicians who screened positive for use of prescription stimulants. Work-related stress was also correlated significantly with usage of stimulants (p < 0.01).

Table 2 illustrates multivariable logistic modeling to identify factors independently associated with the presence of prescription stimulant use.

Table 2
Frequency of stimulant use by medical discipline

Response Predictor OR p-Value

Use of prescription stimulants Age 0.92 0.01

Hours worked per week 0.91 0.04

Male (vs. female) 0.59 0.04

Partnered (vs. single) 1.4 0.01

Children (vs. not) 0.85 0.02

Work family conflict (vs. none) 1.2 0.02

Work related stress (vs. none) 1.4 0.04

Burnout (vs. none) 1.4 0.03

Emergency vs. Internal Medicine 1.8 0.007

Surgery vs. Internal Medicine 1.9 0.005

Anesthesiology vs. Internal Medicine 1.6 0.003

Response	Predictor	OR	p-Value
Use of prescription stimulants	Age	0.92	0.01
	Hours worked per week	0.91	0.04
	Male (vs. female)	0.59	0.04
	Partnered (vs. single)	1.4	0.01
	Children (vs. not)	0.85	0.02
	Work family conflict (vs. none)	1.2	0.02
	Work related stress (vs. none)	1.4	0.04
	Burnout (vs. none)	1.4	0.03
	Emergency vs. Internal Medicine	1.8	0.007
	Surgery vs. Internal Medicine	1.9	0.005
	Anesthesiology vs. Internal Medicine	1.6	0.003

Use of prescription stimulants was strongly associated with age (for each year of age) (OR = 0.92; p = 0.01), hours worked (for each additional hour) (OR = 0.91; p = 0.04), male versus female gender (OR = 0.597; p = 0.04), partnered versus single (OR = 1.4; p = 0.01), having children (OR = 0.85; p = 0.02), screening positive for work-related stress (OR = 1.407; p = 0.04) and burnout (OR = 1.4; p = 0.03), and work family conflict (OR = 1.21; p = 0.02) after controlling for other personal or professional characteristics.

Prescription stimulant use was associated with medical specialty: Emergency Medicine versus Internal Medicine (OR = 1.8; p = 0.007), Surgery versus Internal Medicine (OR = 1.97; p < .005), and Anesthesiology versus Internal Medicine (OR = 1.6; p < 0.003).

4 Discussion

This study is one of few studies that investigates the prevalence of neuro-enhancement among physicians. Moreover, this study analyzed motives and reasons for taking neuro-enhancers and associations between the use of prescription or illegal stimulants and person-centered outcomes (i.e. quality of life).

4.1 Prevalence

The findings of this current study indicate that 8% of all surveyed physicians have used prescription or illicit drugs at least once in their lifetime. As demonstrated there are only few studies focusing on physicians’ behavior. These study results can be compared with the results of the study performed by Franke et al. showing a prevalence of approximately 9% [5].

Prevalence of neuro-enhancement has frequently been analyzed in student populations. Two studies have investigated prevalence outside the academic context [28, 29]. In the study by Dietz et al. the lifetime prevalence for the use of any drug for neuro-enhancement was 88% and for the use of illicit and prescription drugs for neuroenhancement 19.0%. In contrast, Sattler and Schunck found a lower lifetime prevalence of 2.96% for prescription drugs [29].

Regarding prevalence rates and associated factors, it is useful to consider several factors as follows: With the exception of the present study, there is an enormous lack of data about neuro-enhancement drug use among employees. A German health insurance company (DAK) performed an online survey study and included 20,000 employed members (referring to the workforce in general). Without accurately distinguishing prescription and over-the-counter drugs, the non-representative DAK study showed a lifetime prevalence rate of 5%. Motives for usage were as followed: ‘depressed mood’, ‘anxiety’, ‘nervousness’, ‘memory deficits’, ‘fatigue’, and ‘problems of concentration’ [5, 30].

Excluding these studies, we only found research studies on students’ substance use for academic performance enhancement. A meta-analysis examining prevalence rate of stimulant usage found a past-year prevalence rate of 5–9% in high schools and universities [31].

We found a slightly higher prevalence rate for physicians’ use of prescription drugs. It can be discussed that performance enhancement is a current phenomenon, that is more prevalent among (younger) physicians, who might be more vulnerable to testing. In addition, younger doctors might have stronger intentions than older physicians to advance their performance [32].

Prescription stimulant use was strongly associated with medical specialty. Emergency physicians, surgeons and anesthesiologists were at higher risk for prescription stimulant use and reported the highest prevalence rates. Pediatricians and neurologists showed the lowest prevalence rates compared to the other disciplines.

No previous studies could be found to compare these results with former study findings. However, studies on general substance abuse among American physicians of different medical specialties found comparable results [33]. In a second study self-reported substance abuse were at highest levels among psychiatrists and emergency physicians, and lowest among surgeons [34].

4.2 Motives and reasons

Study participants reported that to advance concentration was the main motive for using neuro-enhancers. This finding is in line with a motive identified in a previous research study [35]. Improved vigilance and cognitive performance as the second and third leading motives, respectively, indicate that the predominant motives were related with addressing the challenges of everyday work life. These results indicate that “academic” motives (to manage stress and workload) explain the majority of prescription and illegal drug use, in accordance with earlier research on this topic [35].

Dietz et al. demonstrated that motives and reasons that predicted neuro-enhancement with illicit and prescription drugs were “curiosity,” “to enhance mood,” ”for a confident appearance,” “stress/pressure to perform,” and “deadline pressure [28].”

An interesting research finding belongs to the reported cognitive improvement as a main motive for using neuro-enhancers. In contrast, several experimental study trials analyzing the pharmacological effects of neuro-enhancers in healthy persons could not identify any long-lasting improvements in cognitive performance [2 , 36].

4.3 Limitations

This study is subject to several limitations. As a possible response bias, this study sample includes only those physicians who were interested in the topic neuro-enhancement. In particular, non-responder especially those who take prescription stimulants may have introduced an underestimation of use in this analysis [37]. In addition, due to the cross-sectional design of the study, we are unable to draw causal conclusions. We are unable to define whether the relations between stimulant usage and burnout, work-related stress etc. are causally related or the potential direction of the effects.

A qualitative study may prove instrumental in further understanding prescription drug-use behaviors among physicians in Germany. Although our study sample has an adequate response rate, our results cannot be generalized to all German physicians. Further quantitative research studies, particularly investigating a nationwide population are strongly encouraged. In addition, further studies should focus on side effects of cognitive enhancement in physicians (e.g. addiction).

4.4 Implications

These results show first indications for health educational interventions. In addition, comparisons focusing on the development of drug-taking behavior at different medical disciplines should be performed in future studies. The results of this study illustrate that neuro-enhancement use is less common than discussed in public.

Prevention and intervention efforts should inform health employees. Some of the physicians may consider neuro-enhancement stimulant use as a strategy for coping with stress. As an implication, it may be suitable to improve other psychological coping and non-pharmacological strategies such as sport activities, sleep, meditation, or relaxation techniques [38 –40] to improve job performance and work–life balances. Furthermore, we recommend providing information for physicians about the risks of the side effects and the development of relevant coping strategies for physicians to handle daily work [41, 42].

Hospitals could offer increased support to reduce physicians’ work-related stress.

5 Conclusions

In conclusion, our study contributes to the field by providing frequencies of various types of stimulant use within a sample of physicians. Despite the current rather low prevalence for neuro enhancing (stimulant-taking) behavior our results may have influence on health-policy decisions and implications.

The presence of neuro-enhancement by drug-taking showed associations with various individual (i.e. age, gender, relationship status) and professional factors (i.e. hours worked).

Our study results may act as a baseline for further data sets. Health promotion for the early identification of problematic consumption in physicians is recommended. Prevention efforts may be improved by developing interventions that specifically target physicians.

Conflict of interest

The authors declare that they have no conflict of interest.

Funding

No funding support was received for this study.

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