Since mid-December of 2019, coronavirus disease 2019 (COVID-19) has been identified in many countries (1). As of February 24^th, 41600 medical staff in China have been fighting in the front line of the anti-epidemic campaign. Of these medical staff, 3387 of them were infected with the novel coronavirus pneumonia, accounting for 4% of all confirmed cases, while 22 died and accounted for 0.8% of the deaths. The front-line medical staff will not only bear the work pressure of overload, but also face the huge risk of infection (2). Stress represents the main environmental risk factor for psychiatric illnesses, and in a long-term stress state, people can be more prone to depression or other mental disease (3), which will also increase the risk of infection (4–6). Therefore, it is necessary to investigate the psychological state of the first-line anti-epidemic medical staff and give them necessary psychological interventions if they have anxiety or depression.

In the current study, we investigated the prevalence and influencing factors of anxiety and depression symptoms in the first-line medical staff fighting against novel coronavirus pneumonia in Gansu, and came to some interesting conclusions: 1) the prevalence rate of anxiety and depression symptoms among doctors was 11.4% and 45.6%, respectively; 2) the prevalence rate of anxiety and depression symptoms among nurses was 27.9% and 43.0%, respectively; 3) a history of depression or anxiety (T=-2.644, p= 0.010, 95%CI: -10.514~-1.481) was a risk factor for anxiety symptoms in doctors, while being male (T=2.970, p=0.004, 95%CI: 2.667~13.521) was a protective factor for depression; 4) a history of depression or anxiety was a common risk factor for anxiety symptoms (T=-3.635, p=0.000, 95%CI: -16.360~-4.789) and depression symptoms (T=-2.835, p=0.005, 95%CI:-18.238~-3.254) in nurses; 5) the results of partial correlation (controlled for gender and history of depression or anxiety) indicated that the total score of positive coping was negatively correlated with the total score of anxiety (r=-0.182, p=0.002) and depression (r=-0.253, p=0.001).

Previous studies had suggested that the mental health status of medical staff was worse than in the general population (15, 16). For example, Kerrien M et al. (17) found that 27% of junior doctors were suffering from depression, while 28.7% were suffering from anxiety. Paiva CE et al. (18) found that 12.3%of doctors had depression (HADS-D ≥ 11), and 19.4% had anxiety (HADS-A ≥ 11). A systematic review of 29 studies showed that the prevalence of anxiety and depression among students in medical schools in Europe, the UK, and elsewhere in the English-speaking world outside of North America was 7.7-65.5% and 6.0-66.5%, respectively (19). Similarly, a cross-sectional survey showed that the prevalence of anxiety symptoms in nurses was 43.4% (20). Another cross-sectional survey indicated that the prevalence rate of anxiety among female nurses was 41.1% (21). Maharaj S et al. (22) found that the prevalence rates of depression and anxiety among Australian nurses were 32.4% and 41.2%, respectively. So, our conclusions were not consistent, and this difference might come from the use of different investigation tools. Interestingly, we found that the anxiety level (X² = 7.019. p=0.011) of nurses was significantly higher than that of doctors, but there was no difference in depression (X² = 0.108. p=0.756) between the two groups. So we need to pay more attention to nurses in order to relieve their anxiety.

In the present study, we found that being male (T=2.970, p=0.004, 95%CI: 2.667~13.521) was a protective factor for depression in doctors. There is considerable discourse surrounding the disproportionate diagnosis of men with depression as compared to women, often times cited at a rate around 1:2 (23). However, the view that depression rates are universally higher in women is challenged, as biological determinants, sex role changes, and social factors might also contribute to this difference (24). What's more, meta-analyses of diagnoses and symptoms show that the gender difference peaks in adolescence but then will decline and remain stable in adulthood, and cross-national analyses also indicate that larger gender differences are found in nations with greater gender equity for major depression, but not depression symptoms (25). But beyond that, a systematic review of nineteen studies indicates that the male gender is significantly associated with suicide in individuals with depression (26). So, the relationship between gender and depressive symptoms needs to be verified by a large-scale longitudinal study.

We also found that a history of anxiety or depression was a risk factor for anxiety symptoms in doctors, and a common risk factor for anxiety and depression symptoms in nurses. Osasona SO et al. (27) found that previous mental illness was significantly associated with anxiety, depression, or general psychiatric morbidity in a sample of inmates in a Nigerian prison. Ahmed A et al. (28) found that a history of depression and stress was associated with depressive and anxiety symptoms in a sample of 615 women in Saskatchewan from pregnancy to 5 years postpartum. Stafford L et al. (29) found that women with a psychiatric history and high neuroticism are at the greatest risk for future morbidity after adjusting for confounders, such as age, education, and living alone. Therefore, our conclusions are consistent.

By using partial correlation analysis (controlled for gender and history of depression or anxiety), we finally found that a positive coping style was a protective factor for anxiety(r=-0.182, p=0.002) and depression (r=-0.253, p=0.001), suggesting that a positive coping style was helpful in resisting negative emotions. Mahmoud JS et al. (30) found that reducing maladaptive coping behaviors might have the most positive impact on reducing anxiety, depression, and stress in young adult college students. Wang Y et al. (31) found that perceived stress had some positive effects on psychological distress, and coping style might be a mediator in this relationship among Chinese physicians. In addition, Holz NE et al. (32) pointed out that stress exposure would increase rates of depression and anxiety in adults, particularly in females, and had been associated with maladaptive changes in the anterior cingulate cortex (ACC), while positive coping styles could help to increase the ACC volume. So our conclusions were consistent.

We have to admit that our research has certain limitations. First, it was just a cross-sectional study that could not establish a causal link. Second, the sample size used was relatively small and therefore reduced the reliability of the study. Third, we used the self-assessment scale to evaluate the depression and anxiety symptoms of the medical staff, which might have a certain result deviation.

The first-line anti-epidemic medical staff have high anxiety and depression symptoms, and adopting a positive coping style will help to improve their negative emotions.

The datasets analyzed in this article are not publicly available because the datasets are part of an unpublished database and the database is still being used for other manuscripts in preparation. Requests to access the datasets should be directed to 156892477@qq.com.

The studies involving human participants were reviewed and approved by the Ethics Committee of the Second Clinical Medical College of Lanzhou University. The patients/participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.

WL and LS contributed to the study concept and design. JZ acquired the data. LZ, HW, and AF collected the data. SX and BY analyzed the data and drafted the manuscript. All authors read and approved the final manuscript.

This work was supported by grants from the China Ministry of Science and Technology (2009BAI77B03), National Natural Science Foundation of China (number 81671402), Clinical research center project of Shanghai Mental Health Center (CRC2017ZD02), the National Key R&D program of China (2017YFC1310501500), the Cultivation of Multidisciplinary interdisciplinary Project in Shanghai Jiaotong University (YG2019QNA10), and curriculum reform of Medical College of Shanghai Jiaotong University.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.