Seasonal variation in neurohormones, mood and sleep in patients with primary open angle glaucoma - implications of the ipRGC-system.

Primary open angle glaucoma is associated with an increased risk of mood and sleep disorders. These adversities have been suggested to relate to a disrupted function of the intrinsically photosensitive retinal ganglion cells (ipRGCs). The ipRGCs are key components in the nonvisual photoreceptive system that mediates light effects on mood, sleep and circadian rhythm. We assessed the diurnal hormone levels, pupillary responses and mood and sleep under seasons with different photoperiods in 24 patients with glaucoma and 24 age- and sex-matched healthy controls to investigate responses to naturalistic seasonal changes in daylight. The patients had moderate-to-advanced glaucoma with substantial visual field defects and reductions in the ipRGC-mediated pupillary responses (p < .001). In winter, compared with summer, patients with glaucoma had higher daytime melatonin concentration (p < .001) and lower nighttime cortisol (p = .002). In winter, the daytime melatonin level was inversely correlated with the ipRGC-mediated pupillary responses in the control group (p = .04). In the control group, there were no significant changes in hormone levels between seasons or any correlations between neurohormone levels and the ipRGC-mediated responses. The two groups showed a similar response to season with lower depression scores in summer compared with winter. In between-group comparison, the nocturnal melatonin level (area under curve from 20:00 h to 08:00 h) in summer was lower in glaucoma compared with controls (p = .03). In winter, nocturnal cortisol (at 04:00 h) was lower (p = .004) and daytime cortisol (12:00 h and 16:00 h) was higher (p = .007) in glaucoma compared with controls. In conclusion, we found that patients with glaucoma displayed a seasonal variation in diurnal hormone levels that was not present in healthy controls. Such neurohormonal changes may contribute to the increased risk of mood and sleep disorders seen in patients with glaucoma.

Depressed Patients Hospitalized in Southeast-Facing Rooms Are Discharged Earlier than Patients in Northwest-Facing Rooms.

BACKGROUND AND AIM: Improvement in patients admitted to inpatient wards with severe depression is slow, and such patients are often discharged with residual symptoms which put them at risk for relapse. New treatments that can speed up recovery are highly desired. This naturalistic follow-up study in a specialized affective disorders unit investigated the impact of daylight on the length of hospital stay and improvement of depression. METHODS: For a period of 1 year, we collected data on sociodemographics, length of stay, vitamin D, and depression severity for patients in an inpatient affective disorders unit. The ward is located with one facade that faces southeast (SE); the opposite one faces northwest (NW) and receives far less light and no direct sunlight during winter. RESULTS: SE-facing rooms received far more daylight than NW-facing rooms. The length of stay was significantly lower in the SE rooms, i.e., 29.2 (±26.8) versus 58.8 (±42.0) days in the NW rooms (p = 0.01). There was a statistically nonsignificant greater reduction of 52.2% in depression severity for the patients staying in the SE rooms compared to 42.2% in the NW rooms, which may nevertheless be clinically relevant. CONCLUSION: Due to the study design, no causality for the observed difference in length of stay can be given, but the results support findings in previous studies of the importance of architectural orientation providing natural daylight as a factor for improvement.