Abstract
Background
In our previous study of workers, blood donors and medical students, students stood out with a higher 1-year prevalence of migraine (28%) and tension-type headache (TTH) (74%). General factors associated with headache were common for all groups except low physical activity. The hypothesis of this study was therefore that a number of psychosocial factors relating to the personal sphere would better explain the high prevalence of migraine and TTH in students.
Methods
The study population consisted of 1042 students (719 females, 323 males, mean age 20.6, range 17–40). Headache diagnoses and associated factors were identified by direct professional semi-structured interview. We also interviewed about the following psychosocial factors: dissatisfaction with study, dissatisfaction with family life, dissatisfaction for personal reasons, bad financial situation, overwork, stress, not enough sleep, insomnia, depressed mood, anxiety, irritability, tendency towards conflicts and not being married. We report psychosocial factors associated with headache according to diagnosis and sex using univariate and multivariate logistic regression analyses.
Results
Several factors were significantly associated with migraine and TTH in the univariate analysis. In the multivariate analysis, two psychosocial factors were statistically significantly associated with migraine in all students: irritability (OR 2.2, 95% CI 1.4–3.6) and overwork (OR 2.2, 95% CI 1.4–3.5). Insomnia (2.7, 95% CI 1.1–6.9) and depressed mood (OR 2.1, 95% CI 1.1–4.2) were associated with migraine only in females. Two psychosocial factors were associated with TTH: dissatisfaction with study in males (OR 2.0, 95% CI 1.0–3.8) and depressed mood in females (OR 1.8, 95% CI 1.0–3.5).
Conclusion
Psychosocial factors from the personal sphere showed significant association with migraine and TTH in students. Such factors should therefore be major targets for preventive efforts to reduce the prevalence of primary headache disorders in students.
Introduction
It is clear from twin studies that genes and environment are of equal importance in migraine (1). The 50% risk attributed to environment is, however, poorly understood. We recently studied the prevalence of primary headaches and possible risk factors associated with migraine and tension-type headache (TTH) in three different social groups. Students had the highest age-stratified prevalence of migraine (28.6%, compared with workers 5.7% and blood donors 11.7%) and TTH (67.1%, compared with workers 31.9% and blood donors 60.2%) (2). Many authors have confirmed a high prevalence of primary headache in students (3–14). However, the causes of this have been investigated only in few studies (3,9,12). Our previous study of factors associated with migraine and TTH in three social groups did not find significant differences in prevalence of general factors associated with headache except low physical activity in students (15). This could not explain the high prevalence of headache in students. The hypothesis of the present study was therefore that psychosocial factors relating to the personal sphere play a more important role and may explain, at least in part, the very high prevalence of headache in students. We used a validated semi-structured professionally conducted face-to-face interview to diagnose according to the International Classification of Headache Disorders, third edition (ICHD-3 beta). A specially designed semi-structured interview about psychosocial factors was used and we included over 1000 students in this study.
Material and methods
Study design
This was a cross-sectional study that was conducted between April and June 2013.
Study population
Overview of study population and clinical characteristics of medical students.
TTH: tension-type headache.
Data collection
All participants were interviewed using a semi-structured face-to-face interview conducted by a neurologist or by trained senior medical students supervised by a neurologist. The neurologist (NRK) performed telephone interviews with the medical students if some details were missing after the first interview. Student interviewers (n = 11) were given relevant literature to study. Next, they had personal teaching by the headache expert and finally they had to complete at least 10 supervised interviews that were not used in the actual study.
Definitions of variables
Our semi-structured interview included five parts: 1) personal data (age, sex, profession, telephone number); 2) information about general associated factors (current smoking, consumption of alcoholic beverages, arterial hypertension, body mass index >25, low physical activity, oral contraceptive use, history of head trauma, family history of headache); 3) detailed characteristics of headache; 4) previous consultations, diagnosis and treatment of headache; and 5) psychosocial factors. The first four data sets have already been published. The present paper deals with psychosocial factors.
We investigated the following psychosocial factors in students: dissatisfaction with study, dissatisfaction with family life, dissatisfaction with personal situation, bad financial situation, overwork, stress, not enough sleep, insomnia, depressed mood, anxiety, irritability, tendency towards conflicts and not being married. Each student was asked the following questions about the presence of these factors and the students only had the option to answer yes or no. Thus, no grading or scales were used.
Do you feel that your study does not fit your expectations or are you dissatisfied with your study? Do you feel that family life becomes boring or are you dissatisfied with family life? Do you feel that you frequently have unfavourable personal situations and are you dissatisfied with this? Do you have financial difficulties or not enough money? Do you feel overworked? Do you feel stress? Do you feel that you sleep too little? Do you have problems with your sleep: cannot sleep well all night, have frequent or early awakenings, or cannot fall asleep? Do you feel that you are unhappy or have depressed mood? Are you frequently becoming anxious without significant reason? Do you often become irritable? Do you have a tendency towards frequent conflicts? Are you married?
Ethical considerations
The Medical Ethics Committee of the Urals State Medical University approved this study. All respondents were informed of the purpose of the survey. Written informed consent was obtained from all participants.
Statistical analysis
The primary outcome variable was the presence of psychosocial factors in subjects with migraine or TTH compared with headache-free subjects. In the latter group, we included subjects with very rare TTH – less than seven episodes of TTH per year. To be totally headache free is rare in the general population (less than 5%) (16) and by comparing only with this extreme group would have reduced the power of our study. We conducted all analyses on the entire cohort, and on males and females separately, in order to study sex differences in associated factors. Crude prevalence of headache disorders was calculated in percentages. Univariate analysis was performed to calculate crude odds ratios (OR) with 95% confidence intervals (CI). The differences between prevalence of psychosocial factors among students were statistically examined by chi-square test. A two-tailed p-value <0.05 was statistically significant. Subsequently, we performed a multivariate logistic regression analysis to identify independent associated psychosocial factors. Each covariate was evaluated individually; those meeting the significance level of p < 0.05 and OR > 1 were then included in multivariate models to identify their independent contributions after adjusting for the presence of all other variables. These factors were analysed in participants with headache (migraine or TTH) compared with participants without headache (including very rare TTH), in males and females. All analyses were processed by SPSS 16.0 and performed by two statisticians (DVG and NVK).
Results
The study population consisted of 1042 medical students: 719 females and 323 males, mean age 20.6 years, range 17–40 (Table 1). One-year prevalence of migraine and TTH in female and male students is shown in Figure 1. Females prevailed among participants with headache. Univariate analysis of psychosocial factors associated with migraine and TTH in all students, female and male students are presented in Tables 2–4. Most of these factors were statistically significantly associated with both migraine and TTH in all students: dissatisfaction with study (OR 1.8; 95% CI 1.2–2.7 for migraine and OR 2.0; 95% CI 1.1–3.2 for TTH), stress (OR 2.3; 95% CI 1.6–3.3 for migraine and OR 1.5; 95% CI 1.1–2.1 for TTH), overwork (OR 3.3; 95% CI 2.3–4.7 for migraine and OR 1.7; 95% CI 1.2–2.2 for TTH), not enough sleep (OR 2.0; 95% CI 1.4–2.9 for migraine and OR 1.4; 95% CI 1.0–1.9 for TTH), depressed mood (OR 3.2; 95% CI 2.1–5.0 for migraine and OR 2.0; 95% CI 1.3–3.0 for TTH), anxiety (OR 2.4; 95% CI 1.5–3.7 for migraine and OR 1.9; 95% CI 1.2–2.9 for TTH), irritability (OR 3.3; 95% CI 2.3–4.7 for migraine and OR 1.8; 95% CI 1.2–2.5 for TTH) and tendency towards conflicts (OR 2.0; 95% CI 1.2–3.6 for migraine and OR 1.8; 95% CI 1.1–3.0 for TTH) (Table 2). All these psychosocial factors had higher ORs for migraine than for TTH and among them, overwork, irritability and depressed mood had the highest ORs (>3 for migraine). Three factors were associated only with migraine: insomnia (OR 2.2; 95% CI 1.3–3.7), dissatisfaction for personal reasons (OR 1.9; 95% CI 1.2–3.0) and bad financial situation (OR 1.6; 95% CI 1.0–2.5).
One-year prevalence (in percentage) of migraine (including migraine without aura, migraine with aura, chronic migraine) and tension-type headache (TTH) (including episodic and chronic TTH and excluding very rare TTH H ronic TTHiseven episodes of TTH per year) in male/female medical students and in all students. Psychosocial factors associated with migraine and tension-type headache (TTH) in all medical students. OR: odds ratio; CI: confidence interval.
Psychosocial factors associated with migraine and tension-type headache (TTH) in female medical students.
OR: odds ratio; CI: confidence interval.
Psychosocial factors associated with migraine and tension-type headache (TTH) in male medical students.
OR: odds ratio; CI: confidence interval.
In male students, we found only one significant factor that was associated with TTH – bad financial situation (OR 1.9; 95% CI 1.1–3.5). All other factors were common for female and male students. Among them, irritability was associated with migraine and TTH in females and males. Anxiety was associated with migraine in females and with migraine and TTH in males.
Results of the logistic regression analysis of psychosocial factors associated with migraine and tension-type headache (TTH) in students.
OR: odds ratio; CI: confidence interval. **p < 0.05, ***p < 0.01.
Discussion
The main result of our study was that many psychosocial factors from the personal sphere showed significant association with migraine and TTH in medical students. Compared with our previous study of general factors, the odds ratios were higher, indicating the possibility of explaining a considerable portion of the environmental risk. It is interesting to note that some psychosocial factors had different prevalence in migraine and TTH as distinct from the general factors studied before (14). Therefore, we discuss migraine and TTH separately. The prevalence of many psychosocial factors was higher in female than in male students. The majority of medical students in our study were females (69%) and females had increased risk of migraine. We therefore subdivided our analysis of psychosocial factors according to sex. We tried to compare the results of our study with previous studies, but such studies in students are scarce and nobody investigated factors associated with TTH in students. Therefore, we used also population-based studies for some comparisons. We have presented the results of both univariate and multivariate logistic regression analysis because they each have merit. Our main conclusions were based on the multivariate logistic regression analysis.
Psychosocial factors associated with migraine
Overwork was indicated by 70% of the students. It was statistically significantly associated with migraine in all students. However, this factor was not analysed before in other studies. Stress was reported by 56% in our study and 25% in other studies (17–20). Stress has previously been associated with migraine in a population-based survey (16).
Not enough sleep was associated with migraine in all students (69%) and in females (72%). Insomnia was also associated with migraine in all students (18%) and in female students (18%). The role of insufficient sleep (<6 hours) was demonstrated previously also in female students (9). Irregular sleep was associated with migraine in medical students in another study (20). Deprivation of sleep and sleep difficulty were frequently associated with migraine in population-based studies (16,21).
Depressed mood was associated with migraine in all students (27%) and in female students (40%) in our study. We did not diagnose depression using rating scales but used self-report. Depression (10%) was the most frequent psychiatric disorder in migraine patients according to a previous study in students (3). Another study in students confirmed this (12). A previous population-based study observed depression in 10–40% of the migraine patients and mood disorders in 13.6% of the patients (21,22). We also found that all kinds of dissatisfactions (by family life/personal reasons/with study) were typical for female students with migraine. These factors have not been studied before.
Anxiety was associated with migraine in all students (27%), in female (27%) and male (29%) students. In students, anxiety disorder was previously observed in 11.2% of the migraine patients (3). Students also showed association between migraine and generalized anxiety, panic attacks and phobia (12). A population-based study found that migraine patients were considerably more anxious than the healthy controls (23). Another population-based study reported a worse quality of life in migraine patients with anxiety disorder and depression compared with the control group, and found that the psychiatric comorbidities had negative effects on the pain severity and number of episodes of headache (24). We did not analyse association of migraine with psychiatric disorders as distinct from other studies (3).
Irritability (58%) was also a very common psychosocial factor associated with migraine in all students, in males and females. However, this factor as well as a tendency towards conflicts (16%) were not studied before.
Psychosocial factors associated with TTH
It was found in our study that dissatisfaction with study, stress, overwork, not enough sleep, depressed mood, anxiety, irritability and tendency towards conflicts were associated with TTH in all students. Our study showed sex-specific factors for TTH. In females, depressed mood and irritability was associated with TTH. In male students, dissatisfaction with study, overwork, stress, not enough sleep, bad financial situation, anxiety and irritability were associated with TTH. There have been no previous studies of these factors in patients with TTH.
Sex-specific association psychosocial factors with migraine and TTH
In the present study, several factors had sex-specific association. They included: dissatisfaction with study and not enough sleep. These factors were associated with migraine in females and with TTH in males. Stress, overwork, anxiety and irritability were factors significantly associated with both migraine and TTH in males. Depressed mood and irritability were associated with both headaches in females. Dissatisfaction with family life and for personal reasons were typical for female students with migraine. Bad financial situation was associated with TTH only in male students. These factors have not been studied before.
Strengths and weaknesses of the present study
The use of a direct validated semi-structured interview assured optimal diagnoses and this is a large study for a direct interview. In contrast to previously, we focused on questions from the personal sphere and this novel approach seemed successful. The same interviewer completed both the diagnostic interview and the interview about psychosocial factors. Thus, bias cannot be totally ruled out, but the use of structured questioning would diminish possibilities of bias. It may have been important to include more questions from the personal sphere and to have used rating scales for depression and anxiety, but we did not have capacity to do so. The inclusion of subjects with very rare TTH in the control group may have influenced the association of risk factors with TTH but this seems unlikely because such rare TTH is almost a normal phenomenon. It did not adversely affect the migraine data but rather improved it because of the larger number in the control group.
Our diagnostic process followed the ICHD-3beta criteria. Therefore, it is valid worldwide and so are the results of our questioning about psychosocial factors. Our results are much more comprehensive than studies in students elsewhere, but where there is a comparable study there seems to be good correlation. Therefore, it is likely that our results in Russian students are also valid for students elsewhere.
Conclusion
Psychosocial factors from the personal sphere showed significant association with migraine and TTH in students. Such factors should therefore be major targets for preventive efforts to reduce the prevalence of primary headache disorders in students.
Clinical implications
Psychosocial factors in students are more important than general factors associated with headache. Students are a particularly vulnerable group in relation to migraine and TTH. Prophylactic measures should be attempted for medical students and probably for other students. Routine headache history should include some factors from the personal sphere such as overwork, insomnia, irritability, depressed mood and dissatisfaction with occupation.
Footnotes
Acknowledgement
We are gratefully acknowledge the following doctors and students who participated at this study: PA Filimonova, KI Fljagina, NI Tsvetkova, EA Korzovatykh, AN Ruzaeva, VV Shirshova, AD Kozlova, TA Troshina, AD Malygina, AM Alent'ev, JuS Drozd and JuV Sarafanova.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.