Reading increases ocular illuminance during light treatment.

BACKGROUND: Bright-light treatment is a safe and effective treatment for the management of winter seasonal affective disorder (SAD). In a recent study, we found that the relative duration of reading was positively associated with likelihood of remission after six weeks of light treatment. METHODS: Two technicians measured the illuminance of a light box with a light meter directed towards the center of reading material that was placed on a table in front of the light box. The measurement was also performed after reading material was removed. The two measurements were performed in a randomized order. Friedman analysis of variance with Wilcoxon post-hoc tests were used to compare illuminance with vs. without reading. RESULTS: The presence of the reading material increased illuminance by 470.93 lux (95% CI 300.10-641.75), p<0.0001. LIMITATIONS: This is a technical report done under conditions intended to mimic those of typical ambulatory light treatment as much as possible. CONCLUSIONS: As reading materials reflect light from the light box, reading during light therapy increases ocular illuminance. If confirmed by future studies using continuous recordings in randomized design, instructing SAD patients to read during light therapy may contribute to a more complete response to light treatment. The downside of specific relevance for students, is that reading, in particular, with bright light in the late evening/early night may induce or worsen circadian phase delay, adversely affecting health and functioning.

Light treatment for seasonal Winter depression in African-American vs Caucasian outpatients.

AIM: To compare adherence, response, and remission with light treatment in African-American and Caucasian patients with Seasonal Affective Disorder. METHODS: Seventy-eight study participants, age range 18-64 (51 African-Americans and 27 Caucasians) recruited from the Greater Baltimore Metropolitan area, with diagnoses of recurrent mood disorder with seasonal pattern, and confirmed by a Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders-IV, were enrolled in an open label study of daily bright light treatment. The trial lasted 6 wk with flexible dosing of light starting with 10000 lux bright light for 60 min daily in the morning. At the end of six weeks there were 65 completers. Three patients had Bipolar II disorder and the remainder had Major depressive disorder. Outcome measures were remission (score ≤ 8) and response (50% reduction) in symptoms on the Structured Interview Guide for the Hamilton Rating Scale for Depression (SIGH-SAD) as well as symptomatic improvement on SIGH-SAD and Beck Depression Inventory-II. Adherence was measured using participant daily log. Participant groups were compared using t-tests, chi square, linear and logistic regressions. RESULTS: The study did not find any significant group difference between African-Americans and their Caucasian counterparts in adherence with light treatment as well as in symptomatic improvement. While symptomatic improvement and rate of treatment response were not different between the two groups, African-Americans, after adjustment for age, gender and adherence, achieved a significantly lower remission rate (African-Americans 46.3%; Caucasians 75%; P = 0.02). CONCLUSION: This is the first study of light treatment in African-Americans, continuing our previous work reporting a similar frequency but a lower awareness of SAD and its treatment in African-Americans. Similar rates of adherence, symptomatic improvement and treatment response suggest that light treatment is a feasible, acceptable, and beneficial treatment for SAD in African-American patients. These results should lead to intensifying education initiatives to increase awareness of SAD and its treatment in African-American communities to increased SAD treatment engagement. In African-American vs Caucasian SAD patients a remission gap was identified, as reported before with antidepressant medications for non-seasonal depression, demanding sustained efforts to investigate and then address its causes.