Master’s student Rob van der Linden is conducting research regarding the effect of seasonal variation and the amount of sunlight on the experienced depressive symptoms in adults with visual impairment.
Depression is a common mental health problem in people with visual impairment. Depression is twice as common in visually impaired people compared to the general population. People who suffer from depression mainly experience a lack of interest in usual life activities, insomnia, inability to enjoy life and even suicidal thoughts. A multitude of factors influence the development of depression in people with visual impairment. Factors that may contribute to the development of depressive symptoms are seasonal variation and the amount of sunlight. One possible explanation for this association could be that blindness and loss of vision may cause a reduction in light transmission from the eyes to the brain and the neural circuitry that maintains normal mood. However, there is currently insufficient evidence for the hypothesis that seasonal variation and the amount of sunlight are associated with sepressive symptoms in this population..
What is the aim of the study?
The aim of this project is to provide additional evidence on the hypothesis that season and sunlight are related to depression in adults with visual impairment, and that the effects differ between: 1) adults who are blind versus adults who have low vision; 2) adults with various eye diseases and; 3) adults who are sensitive to bright light versus those who are not.
How do we conduct the study?
This project uses data from seven previous studies conducted in the period 2009-2016. The population includes visually impaired people aged 18 and over. These people were recruited from rehabilitation organizations for people with a visual impairment in the Netherlands (‘Bartiméus’ and ‘Royal Dutch Visio’). Depressive symptoms were measured by means of two different self-reported questionnaires. The season is determined on the basis of the date of completion of the self-reported questionnaires and the hours of sunshine are retrieved from the Royal Netherlands Meteorological Institute (KNMI). The hours of sunshine are collected at the weather station closest to each participant’s zip code. Statistical analyses are used to investigate the possible effect of season and hours of sunshine on experienced depressive symptoms in this population.