Fig. 3
Scatter plots of PSQI scores and overall VFQ scores. (A) Scatter plot showing the relationship between PSQI scores and overall VFQ scores across all participants. A significant negative correlation is observed, indicating that higher PSQI scores are associated with lower overall VFQ scores (R2 = 0.2607, P < 0.001), suggesting that poorer sleep quality is linked to worse visual function. (B) In the control group, a negative correlation between PSQI scores and overall VFQ scores is also observed (R2 = 0.1739, P < 0.001). This suggests that even in non-DM individuals, reduced sleep quality adversely affects visual function. (C) In the DM group, the negative correlation between PSQI scores and overall VFQ scores is more pronounced (R2 = 0.2427, P < 0.001). Compared to the control group, the impact of poor sleep quality on visual function is greater in the DM group, indicating that DM patients are more sensitive to the effects of sleep quality on visual function. PSQI: pittsburgh sleep quality index; VFQ: visual function questionnaire; DM: diabetes mellitus; Con: control.
