Seasonal Affective Disorder and Visual Impairment

Psychiatric Centre Rigshospitalet

Status: Completed

Conditions: Seasonal Affective Disorder; Visual Impairment

Treatments: Device: light therapy

Study type: Interventional

Funder types: Other

Identifiers

NCT03403959

BlindSAD

Details and patient eligibility

About

As a subtype of major depressive disorder, seasonal affective disorder (SAD) or winter depression causes severe reductions in both quality of life and productivity and results in high morbidity and frequent sick leave (1). SAD is a prevalent disorder with rates as high as 3-5% in central European countries and 8-10% in Scandinavian countries. In our recent screening survey among persons with severe visual impairment or blindness (visual acuity < 6/60), we found a strikingly high prevalence of SAD of 17 % compared to 8% in the fully sighted control group. Persons with maintained light perception had a highly increased SAD prevalence of 18 % whereas no light perception (NLP) respondents had an SAD prevalence of 13 %. Light is unquestionably of great importance in the development and treatment of SAD. It is suggested that a reduced retinal sensitivity to light leads to sub-threshold light input to the brain and consequently to the development of SAD. The novel retinal non-visual photoreceptors, the intrinsically photosensitive retinal ganglion cells (ipRGCs), are involved in the regulation of circadian rhythm and mood and their function are in part independent of the function of the classical rod and cone photoreceptors which form the basis of conscious visual perception. Function of the ipRGCs can be assessed by chromatic pupillometry where the sustained pupillary contractions following blue light stimulation (PIPR) is the main outcome. In persons with SAD without eye disorder the function of the ipRGCs is reduced. We here wish to investigate associations between ipRGC function and SAD symptoms, circadian profile and treatment response to light therapy in persons with visual impairment.

Persons with visual impairment (SAD and non-SAD) are assessed for ipRGC function with chromatic pupillometry, for seasonal mood variation by interview and questionnaire and for diurnal melatonin secretion by saliva analysis summer and winter. In winter SAD participants are treated with daily morning bright light for 6 weeks. Reduction in depression scores and tolerability is recorded.

Enrollment: 18 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Seasonal affective disorder. Visual impairment (Snellen visual acuity < 6/18) or visual field reduction (MD<10).

Exclusion criteria

Alcohol or drug abuse. Current or planned pregnancy. Other neuropsychiatric disorder. Antidepressant medication. Regular use of melatonin.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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18 participants in 2 patient groups

SAD

Experimental group

Description:

Persons with visual impairment and SAD are assessed by clinical interview, depression rating, diurnal saliva melatonin and cortisol and chromatic pupillometry during symptomatic winter phase and asymptomatic summer phase. Winter assessment is followed by a 6 week light therapy protocol ending with assessment of depression severity and repeated pupillometry.

Treatment:

Device: light therapy

non-SAD

No Intervention group

Description:

Control participants with similar visual impairment but without SAD/sSAD are assessed by clinical interview, depression rating, diurnal saliva melatonin and cortisol and chromatic pupillometry in winter and summer.