Optimized light therapy for non-seasonal major depressive disorder: Effects of timing and season

Background:The cause of depression is largely unknown, but several studies point to disturbances of biological rhythmicity. The functioning of the suprachiasmatic nucleus (SCN) is impaired, as evidenced by an increased prevalence of day-night rhythm perturbations, such as sleeping disorders. Moreover, the inhibitory SCN neurons on the hypothalamus-pituitary adrenocortical axis (HPA-axis) have decreased activity and HPA-activity is enhanced, when compared to non-depressed elderly. Using bright light therapy (BLT) the SCN can be stimulated. In addition, the beneficial effects of BLT on seasonal depression are well accepted. BLT is a potentially safe, nonexpensive and well accepted treatment option. But the current literature on BLT for depression is inconclusive.Methods/design:RCT (ClinicalTrials.gov identifier: NCT00332670) in 89 subjects, of 60 years and older with a diagnosis of major depressive disorder. After inclusion subjects were randomly allocated to the active (BLT) vs. placebo (dim red light) condition. just before the start of light therapy, after completion of three weeks therapy period, and three weeks thereafter several endocrinological, psychophysiological, psychometrically, neuropsychological measures are performed:Results:Main effect analyses on HADRS-17 scores revealed significant antidepressant effects from BLT. Primary results will be presented.Discussion:BLT reduces nonseasonal depression in elderly patients. Additional lightning may easily be implemented in the homes of patients to serve as add-on treatment to antidepressants or as a stand-alone treatment in elderly depressed patients. Our data support the role of a dysfunctional biological clock in depressed elderly subjects, such a finding may guide further development of novel chronobiological oriented treatment strategies.

Download Full-text

A systematic review of light therapy on mood scores in major depressive disorder: light specification, dose, timing and delivery

International Journal of Basic and Applied Sciences ◽

10.14419/ijbas.v5i1.5456 ◽

2015 ◽

Vol 5 (1) ◽

pp. 30 ◽

Cited By ~ 1

Author(s):

Mohammad Alotaibi ◽

Mark Halaki ◽

Chin-Moi Chow

Keyword(s):

Major Depressive Disorder ◽

Depressive Disorder ◽

Sleep Problems ◽

Light Exposure ◽

Light Emitting Diode ◽

Mode Of Delivery ◽

Light Therapy ◽

Exposure Dose ◽

Major Depressive ◽

Mortality And Morbidity

Background: Depression is associated with prolonged disability, mortality, and morbidity. Ninety percent of patients with Major depressive disorder (MDD) have sleep problems. Light therapy has been shown to be effective in treating sleep disorders and MDD. This review aims to assess the characteristics (colour, intensity), exposure dose (duration and timing) and the mode of delivery (light boxes, visor etc) of light in reducing depression, measured by mood scores, in MDD.Method: a systematic literature search was performed on 6 major databases. The Physiotherapy Evidence Database (PEDro) Scale was applied to assess study quality.Result: Twenty-four articles satisfied the inclusion criteria. Effective light intensities varied from 176 -10,000 lux. Effective modes of delivery included light box, table lamp, visor and light emitting diode (LED) glasses. Effective light colours included white, green, and blue with the white colour being the most commonly used. The duration of light treatment ranged from 30 min to 2 h, and evening light generally improved mood.Conclusion: Light therapy, with exposure durations in the range of 30 min to 2 h per day, intensity range of 176 to 10,000 lux, in any of blue, green, or white light colour and exposure during morning mostly demonstrated a positive change in mood effects. Factors other than the light properties, such as anti-depressant medication use, depression episodes and severity, natural light exposure and sleep deprivation may confound the effects of light therapy.

Download Full-text