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Chronotyping glaucoma patients with the Munich ChronoType Questionnaire: A case-control study.
Ronald A J M Bierings1, Marijke C M Gordijn2,3, Nomdo M Jansonius1
1Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Plos One
|March 29, 2019
Summary
Glaucoma patients showed no significant changes in their main sleep timing (chronotype), but severe cases exhibited increased variability. This suggests the eye disease may subtly alter sleep patterns, particularly in advanced stages.
Area of Science:
- Ophthalmology
- Chronobiology
- Neuroscience
Background:
- The circadian clock, crucial for regulating sleep-wake cycles, is influenced by light via intrinsically photosensitive retinal ganglion cells.
- Glaucoma, characterized by retinal ganglion cell loss, may therefore impact an individual's chronotype.
- Understanding this potential link is important for managing glaucoma patients' overall health.
Purpose of the Study:
- To investigate and compare the chronotype of glaucoma patients with that of healthy control subjects.
- To determine if glaucoma disease severity correlates with changes in chronotype.
Main Methods:
- The Munich ChronoType Questionnaire was administered to 221 glaucoma patients and their spouses (primary controls).
- After excluding shift workers and alarm-dependent sleepers, 159 glaucoma patients and 163 controls were analyzed.
- Chronotype was assessed using mid-sleep on days off, corrected for sleep debt (MSFsc), with comparisons made to a large online citizen-science cohort.
Main Results:
- Glaucoma did not significantly alter the mean MSFsc compared to the primary control group (P = 0.62).
- However, chronotype variability appeared to increase with glaucoma severity (severe glaucoma vs. controls, P = 0.023).
- Glaucoma patients' mean MSFsc was significantly earlier than the secondary online control group (P = 0.024).
Conclusions:
- No clear chronotype changes were observed in early to moderate glaucoma patients.
- Severe glaucoma may be associated with increased chronotype variability and a slight advancement in sleep timing.
- Further research is needed to fully elucidate the relationship between glaucoma and circadian rhythm regulation.
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