The association between clinically diagnosed insomnia and age‐related macular degeneration: a population‐based cohort study

Abstract

Purpose The decreased level of melatonin, the substance involved in the control of the sleep–wake cycle, has been reported among the patients with age‐related macular degeneration (AMD). However, knowledge about the relationship between sleep disturbance and AMD is still limited. This longitudinal case–control study aims to investigate the risk of incident AMD among the patients with clinically diagnosed insomnia using the Taiwan National Health Insurance Research Database. Methods The insomnia cohort (n = 15 465) consisted of newly diagnosed insomnia cases aged ≥55 years between 2000 and 2009. Subjects without insomnia, matched for age, gender and enrolment time, were randomly sampled as the control cohort (n = 92 790). Cox proportional hazard regressions were performed to calculate the hazard ratios (HR) of incident AMD for the two cohorts after adjusting for potential confounders. Results Of the 108 255 sampled subjects, 2094 (1.9%) were diagnosed with AMD, including 214 (0.2%) with neovascular AMD, during a mean follow‐up period of 5.1 ± 2.8 years. Insomnia patients were more likely to have subsequent AMD than those without insomnia (2.5% versus 1.8%, p < 0.001). Further, the incidence of exudative AMD was also higher in the insomnia cohort than the control cohort (0.3% versus 0.2%, p = 0.002). The adjusted HR was 1.33 (95% confidence interval [CI], 1.18–1.48, p < 0.001) for AMD and 1.67 (95% CI, 1.20–2.33, p = 0.002) for exudative AMD. Conclusions Clinically diagnosed insomnia is an independent indicator for the increased risk of subsequent AMD development.

Associations between age‐related macular degeneration and sleep dysfunction: A systematic review

“…Two studies explored only sleep dysfunction as an exposure. 36,37 One study explored only AMD as an exposure. 24 Three studies explored either sleep dysfunction or AMD as an exposure.…”

“…Two were case-control studies, 24,39 three were longitudinal cohort studies, 28,36,37 and one was a clinic-based cross-sectional study. 38 The two case-control studies 24,39 and the cross-sectional study, 38 measured sleep quantity and quality using self-reported questionnaires.…”

Sleep, pain, and neurodegeneration: A Mendelian randomization study

“…To date, evidence from observational studies has shown a remarkable heterogeneity in the association of different circadian traits with various NDDs. A recent study investigating the incidence of AMD in 108,225 participants observed that INS patients were 33% more likely to have subsequent AMD (HR 1.33, 95% CI 1.18, 1.48) 5 . Previously, an observational study of 57 patients with neovascular AMD and 108 controls found a significantly increased risk of neovascular AMD in patients sleeping less than 6 hours compared to those sleeping 7-8 hours (OR 3.29, 95% CI 1.32, 8.27) 64 .…”

Sleep, Pain, and Neurodegeneration: A Mendelian Randomization Study

“…To date, evidence from observational studies has shown a remarkable heterogeneity in the association of different circadian traits with various NDDs. A recent study investigating the incidence of AMD in 108,225 participants observed that patients with INS were 33% more likely to have subsequent AMD (HR 1.33; 95% CI 1.18, 1.48) ( 34 ). Previously, an observational study on 57 patients with neovascular AMD and 108 controls found a significantly increased risk of neovascular AMD in patients sleeping <6 h compared to those sleeping 7-8 h (OR 3.29; 95% CI 1.32, 8.27) ( 35 ).…”