Prospective study of pain and psychological symptoms of first-year university students

A slightly increasing trend of frequent pain and psychological symptoms has been shown both in Finnish adolescents and in university students during the past decades [1-4]. In university students, the prevalence of weekly neck pain increased from 25% to 29%, low back pain from 10% to 14% and overall psychological distress from 22% to 28% during the period from 2000 to 2012 [3,4]. In cross-sectional studies comparing the prevalence of both pain and psychological symptoms in adolescents and young adults, these symptoms have mostly been reported to increase with age [2-7]. The university entry is potentially a vulnerable and demanding period with long-lasting health consequences. In this transitional phase from adolescence to adulthood, students may be more prone to experience increased psychological distress and general health problems [8,9]. These health problems have been regarded important to be taken into account in the irst study year for the purpose of preventing health problems in the later phase of the studies and mainting ones’s studying capacity and future working ability.


Introduction
A slightly increasing trend of frequent pain and psychological symptoms has been shown both in Finnish adolescents and in university students during the past decades [1][2][3][4]. In university students, the prevalence of weekly neck pain increased from 25% to 29%, low back pain from 10% to 14% and overall psychological distress from 22% to 28% during the period from 2000 to 2012 [3,4]. In cross-sectional studies comparing the prevalence of both pain and psychological symptoms in adolescents and young adults, these symptoms have mostly been reported to increase with age [2][3][4][5][6][7]. The university entry is potentially a vulnerable and demanding period with long-lasting health consequences. In this transitional phase from adolescence to adulthood, students may be more prone to experience increased psychological distress and general health problems [8,9]. These health problems have been regarded important to be taken into account in the irst study year for the purpose of preventing health problems in the later phase of the studies and mainting ones's studying capacity and future working ability.
To our knowledge, however, the prognosis of different pain and psychological symptoms especially in university students has not previously been studied using a prospective study design. The aim of our study was to examine the incidence and outcome of pain and psychological symptoms in a fouryear follow-up study of irst-year university students. Our hypothesis was that both frequent pain and psychological symtoms including overall psychological distress in Finnish university students increase signi icantly from the irst study year to the fourth study year. the respodents' current life. Responses for all 12 symptoms were scored as 0: "no problem" (not at all; same as usual), and 1: "problem" ("somewhat more than usual"; "much more than usual"). The score 4-12 is considered as an indication of psychological distress [13,14].

Statistical analysis
Descriptive values are expressed as frequencies and percentages. Changes in pain and psychological symptoms were analyzed using the proportional-odds cumulative logit model for repeated measures, since the same students participated twice. In the model, overall differences between genders were tested, and changes over time and the gender x time interaction were also included to ind possible gender differences in changes over time. p -values (two-tailed) less than 0.05 were considered as statistically signi icant. Statistical analyses were conducted using SAS for Windows, version 9.3 (SAS Institute, Cary, NC, USA). The study design and the informed consent procedures were approved by the Joint Ethics Review Committee of the Turku University Medical Faculty and the Turku University Central Hospital.

Results
In 2008, a total of 820 of the 2750 respondents (female N=1750, male N=1000) were irst-year students, and of them, 416 (female N=283, male N=133) answered the irst questionnaire. Of these 416 students, 242 still continued their studies four years later, and were invited to follow-up study in 2012. Fifty one percent (123/242; female N=93, male N=30) agreed to participate and re-illed the questionnaire second time in their fourth study year. Table 1 shows the 4-year persistence and the incidence of symptoms from the irst to the fourth study year. Of the irst-year students with frequent symptoms in 2008, one half (47% -65%) still reported that they had the same frequent symptoms in their fourth study year. The most permanent symptoms were neck pain, psychological tension and overall psychological distress. Of the headache-free irst-year students 20% (p < 0.05) reported frequent headache in the follow-up. The majority (78% -95%) of the symptom-free irst-year students remained symptom-free in the follow-up as well.

Discussion
To our knowledge, this is the irst prospective outcome study of university students with and without frequent pain or frequent psychological symptoms. The prognosis of symptoms was better than we suspected. It was surprising that the incidence of new symptoms was low. On the other hand, perceived symptoms of the students including overall psychological distress was remained quite persistent from the irst study year to the four-year follow-up.
Even if previous cross-sectional studies have raised a health survey conducted at four-year intervals among Finnish university students (Student Health Survey, N=128 600-152 196 per year in 2000-2012). The study population has been described earlier [3]. In Finland, all full-time university students are entitled to receive health care services provided by the Finnish Student Health Service (FSHS). The FSHS registers were used for a systematic sampling of the study population. This study was designed as a prospective cohort study of irst-year students. The students have received prior written information on the follow-up study. Those irst-year students who answered the irst questionnaire in 2008 were specially invited and asked to re-ill the questionnaire second time in 2012.
In 2008, a random sample (N=4983) of all 19-34-yearold undergraduate students (N=152 196) received a selfadministered questionnaire. The participation rates of this follow-up study are shown in a low chart (Figure 1).
The methodology of this nationwide student health survey has been described previously [3,10,11]. The present study focused on a prospective cohort of irst-year university students.
The questionnaire both at baseline year 2008 and in the follow-up year 2012 consisted of items of physical, mental and social health. The frequency of pain (neck, low back, limb or joint pain, headache) and of psychological symptoms (depressiveness, anxiety, concentration problems, psychological tension) during the past month were categorized to "no symptoms" (never; occasionally), and "frequent symptoms" (weekly; daily) [3,10,11].
The General Health Questionnaire (GHQ-12) was used to rate the students' overall psychological distress within the past weeks [12]. The measure includes questions regarding question of possible poor prognosis of symptoms in student populations [1][2][3][4], this suspicion was not con irmed by our prospective study of irst-year students. Only half of frequent symptoms were reported to persist after four years, while another half had alleviated. On the other hand, the incidence of new frequent symptoms was evident only in less than a quarter, while most of symptom-free students remained symptom-free four years later for all symptoms. The study with university population has also demonstrated mild musculoskeletal complains at baseline and overall stable course during one year follow-up [15]. On the other hand, Liu, et al. reported in their recent longitudinal four-year study in a Chinese context that there were differences in the psychological health states of different years. Especially the depression, anxiety, and stress all appeared in the irst or second year, but some improvements were achieved in the third and last years [16]. It seems possible that pain and psychological symptoms during the irst four years are transient without a clear sign of chroni ication. Our study design does not, however, allow for the estimation of previous adolescent years. Even if our study population was nationally representative, our results remain suggestive due to the low number of irst-year students. The most likely reason for low response rate was the extensive and demanding questionnaire including altogether 168 questions of f.ex. physical, mental, social health and health behavior. It is also possible that the timing of data collection in the spring when students are busy with their studies and exams was not favorable for this student group. In a small study population, the risk of bias is always possible, despite of all efforts to keep study phases and questionnaires identical. Due to the selection effect the true course might not be so favorable than the results suggest.
Because of the surprising results in our study population, other prospective studies are needed in order to con irm the results and to describe the impact of these symptoms on students' life. Moreover, identi ication of possible risk groups of students could help in designing effective prevention interventions.

Conclusion
Our indings indicate that pain and psychological symptoms in university students are rather persistent. On the other hand, half of those with frequent symptoms become symptomless and prognosis of symptom-free students is favorable. This inding emphasizes need for further cohort studies on the subject.