Abstract
BACKGROUND: Grit, defined as the perseverance and passion for long-term goals, plays an essential role in academic success and resilience in the medical profession. Previous cross-sectional studies have indicated an association between higher grit and fewer depressive symptoms among medical residents. However, no longitudinal studies have examined the association between grit and later depressive symptoms during residency training. Therefore, this study explored the association between grit at the start and depressive symptoms at the end of the first-year postgraduate (PGY1) residency among Japanese medical residents. METHODS: This longitudinal study analyzed data from all first-year postgraduate residents at the Tokyo Medical and Dental University in Tokyo, Japan, from 2021 to 2023. We administered the surveys at the start and end of PGY1. We assessed grit using the Japanese version of the Short Grit Scale (Grit-S) and depressive symptoms using the Center for Epidemiologic Studies Depression Scale. We examined the association between grit at the baseline and depressive symptoms at the end of PGY1 using logistic regression analysis. RESULTS: Of the 146 residents, 28 (19.2%) exhibited depressive symptoms by the end of PGY1. After adjusting for baseline depressive state, age, sex, university attended, sleeping hours, and training program, a 1-unit increase in the Grit-S score was associated with a significantly reduced likelihood of depressive symptoms (adjusted odds ratio [AOR]: 0.43; 95% confidence interval [CI]: 0.18-0.98). The crude analysis indicated that the perseverance of effort score was associated with a smaller reduction in the risk of having depressive symptoms at the end of PGY1 (AOR: 0.51; 95% CI: 0.29-0.93); however, the consistency of interest score was not (AOR: 0.56; 95% CI: 0.30-1.05). CONCLUSION: This study demonstrated that, among Japanese medical residents, higher grit at the start of residency is significantly associated with a lower risk of depressive symptoms by the end of PGY1. CLINICAL TRIAL NUMBER: Not applicable.