The association between depressive symptoms and self-rated health among university students: a cross-sectional study in France and Japan

Background Depressive disorders in University students have risen dramatically in the past few decades to the extent that students’ mental health has become a current global public health priority. Obtaining information from University students about their mental health is challenging because of potential embarrassment of disclosing one’s concerns and fear of stigmatization. Self-rated health might be a good solution to evaluate mental health state by a simple and neutral indicator. The aim of the study is to investigate the association between depressive symptoms and self-rated health by sex among University students in France and Japan. Methods A cross-sectional study was conducted by using two large cohorts of students aged ≥18 years ( n = 5655 in Bordeaux, France and n = 17,148 in Kyoto, Japan). Depressive symptoms (PHQ-2 scale), Likert scale of self-rated health, socio-demographic characteristics and health habits were collected through self-administered questionnaires. Multivariate logistic regression models were performed to describe the association between depressive symptoms and other variables including self-rated health, stratified by sex. Results A high score of PHQ-2 (high depressive symptoms) was associated with poor self-rated health in both cohorts independently of all other variables (OR 2.82, 95%CI 1.99–4.01 in France, OR 7.10, 95%CI 5.76–8.74 in Japan). Although the prevalence of depressive symptoms between sexes was different in French students (males 15.4%, females 25.0%, p < 0.001), it was similar in Japanese students (males 3.5%, females 3.3%, p = 0.466), who reported less depressive symptoms than French students. The association between depressive symptoms and poor self-rated health was greater in Japanese females (OR 12.40, 95%CI 7.74–20.00) than in males (OR 6.30, 95%CI 4.99–7.95), whereas the strength of the association was almost similar in French students (OR 2.17, 95%CI 0.86–5.47 in males, OR 2.98, 95%CI 2.03–4.38 in females). Conclusions Depressive symptoms were associated with self-rated health among University students in both countries with slightly differences in sex. Self-rated health would be a simple, reliable and universal indicator for healthcare professionals and University staff to identify students at risk of depression.