Association of Poor Quality of Sleep with Vision-Threatening Diabetic Retinopathy: A Matched Case–Control Study

INTRODUCTION: Vision-threatening diabetic retinopathy, a long-term microvascular complication of diabetes in the eye, is a major cause of blindness worldwide. Sleep is regulated by a special area of the brain, and poor quality of sleep has been implicated in long-term diabetic complications, including diabetic retinopathy. The study was aimed at exploring whether poor sleep quality is associated with the likelihood of developing vision-threatening diabetic retinopathy. METHODS: A matched case–control study was conducted from 6 May 2022 to 6 September 2022. The study was based on patients with diabetes (both type 1 and type 2), attending a retina clinic of the referral center. Patients with confirmed vision-threatening diabetic retinopathy were defined as cases and matched with control study subjects. Rating of sleep quality was done by Pittsburgh Sleep Quality Index assessment tool. Conditional logistic regression model was applied to assess the effect of overall poor sleep quality on vision-threatening diabetic retinopathy. RESULTS: The study recruited a total of 126 (63 duration-matched pairs) patients with diabetes. The overall quality of sleep was poor among 71.90% of patients in the case groups, significantly higher compared with those of the control groups (28.10%) (p < 0.00). The mean quality of sleep for cases [mean (M) = 7.10, standard deviation (SD) = 4.30] was higher than the control group (M = 3.60, SD = 2.70). The magnitude of the difference [M difference = 3.50, 95% confidence interval (CI): 2.25–4.75] was significant. Poor sleep quality predicted the chance of developing vision-threatening diabetic retinopathy in a diabetic cohort. CONCLUSIONS: This study revealed a significant association between the overall poor quality of sleep and vision-threatening diabetic retinopathy. Co-management of sleep disruption and vision-threatening diabetic retinopathy, and better sleep advisory are warranted.