The Effects of Confinement on Sleep Quality and Level of Interest in University Students [Letter]

Dear editor

We would like to comment on the recent cross-sectional study by Martínez-Lezaun et al¹ regarding the impact of confinement due to COVID-19 on the quality of sleep and interests of students across different Spanish universities. The authors concluded that confinement is associated with worsened quality of sleep and reduced activity. As medical undergraduates ourselves, we have personally observed the high prevalence of this matter being discussed in community-based settings (GP practices) in the UK. We recognize the importance of good sleep hygiene and we strongly resonate with the study participants with regards to how the lockdown can negatively affect health and sleep. The authors have enlightened us with useful insights into this topic of interest; however, we would like to address several issues, in hopes of informing future research in this area of study.

Firstly, potential confounders including the effects of unfavorable living conditions and lower socioeconomic status,² both of which could have been precipitated by confinement, were not adequately addressed in this study. Other lifestyle factors might have also played a role in the deterioration of sleep quality. Examples of such factors include smoking, alcohol and caffeine consumption, as suggested by Fischer et al.³ Additionally, as the participants were recruited across different years of study, there would have been an inherent variation in academic commitments, which in and of itself might have pre-determined their quality of sleep. This echoes with the findings of a study by Rezaei et al⁴ which reported poorer sleep quality in students of later year groups. Thus, future studies may benefit from recruiting a more homogeneous study population (ie limiting participants to one year group).

Furthermore, this study employed two seemingly arbitrary time intervals (ie 20 and 40 days) during which the sleep quality and interests in activity were assessed. We are curious as to why these specific intervals were utilized, and their significance in determining how much the students’ sleep quality and interests have changed pre- and mid-confinement. The authors aptly noted the lack of statistically significant differences when comparing the sleep quality between these two timepoints (M2 and M3). We suggest lengthening the window of time from 20 days to one month, considering the latter has been used as the reference period for the Pittsburgh Sleep Quality Index.⁵

In summary, the authors have prudently elucidated the undesirable repercussions on the quality of sleep and interests in activities among university students due to confinement during COVID-19. This study necessitates further exploration into solutions that can promote sleep hygiene amidst this pandemic, in hopes of improving the wellbeing of university students.