Objective: Recently, it has been shown that daylight has an antidepressant effect and bright light therapy is a treatment method on depression of which efficacy has been proven. We will present a cross-sectional study in terms of daylight effect on our hospital population.
Methods: A total of 248 patients, who were hospitalized in The Hospital of Ataturk University Medical Faculty between December 2014-February 2014 were included in the study. Patients (106 female, 142 male) were divided into two groups; 146 were in rooms getting daylight at least 3 hours and 102 were in rooms getting less than 3 hours per day, with no differences age and gender. Anxiety and depression symptoms of patients were screened by using the Hospital Anxiety Depression Scale. Individuals having a central nervous system or psychiatric disorder and using psychotropic medications were excluded.
Results: Of the patients, 48 were hospitalized in a surgery department and 200 were hospitalized in an internal medicine department. The mean age of the patients was 52.5±17.7 years. The average length of hospitalization was 11.2±17.2 days, and mean d of hospitalization was 3.5±3.7 days, respectively. Anxiety subscale score was 19.3±3.5 in the group of daylight and 19.4±4 in the group of less daylight, respectively. Depression subscale score was 16.6±2.8 in the group of daylight and 17.6±3.4 in the group of less daylight, respectively. Between groups, anxiety subscale scores were not statistically different (p=0.76), however depression subscale scores were statistically different (p=0.01). No difference was found among depression and anxiety scores between individuals those staying in a single room and multi-person room (p=0.62, p=0.69, respectively), number of hospitalizations (p=0.58, p=0.12, respectively) and duration of hospital stay (p=0.47, p=0.57, respectively). According to gender, anxiety score of males with daylight was 19.8±3.5 and without daylight was 21±3.9. Anxiety score of males with less daylight were lower than those of daylight group but did not differ significantly (p=0.79). Depression score of males with daylight was 16.6±2.8, without daylight was 17±3.3. Depression score of males with daylight were lower when compared to those without daylight but did not differ statistically (p=0.50). Among females, anxiety score with daylight was 18.2±3.8, without daylight was 18.7±3.5 and did not differ between the groups (p=0.47). Mean depression score of females with daylight was 16.6±2.8, without daylight was 18.9±3.1 and a significant difference between groups was found (p<0.001).
Conclusion: In the light of these results, the effects of sunlight on decreasing depression symptoms may be more pronounced in females than males, however anxiety symptoms may not be affected by having daylight or not. We did not make a psychiatric diagnostic interview; this is a limitation of this study. Antidepressant effect of daylight needs to be studied with further studies.