Bright Light Therapy Can Help Treat Symptoms of Major Depression
Depression is common among the elderly. Late-life depression is thought to affect about 6 million Americans aged 65 and older. Antidepressants are just as effective in older adults as they are in younger people, but the drugs carry potentially serious side effects. A small clinical trial from The Netherlands suggests that bright light therapy can reduce symptoms of major depression with much fewer risks.
Light Therapy Affects Same Brain Structures as Antidepressants
Dr. Ritsaert Lieverse of the VU University Medical Center in Amsterdam studied 89 adults aged 60 or older who had been diagnosed with clinical or major depression. About half were randomly assigned to bright light therapy for an hour each morning for three weeks while the control group used similar light box that emitted a dim red light rather than a pale blue light. Dim red light has no known benefits or detrimental effects on humans.
A light therapy system consists of a set of bright (7500 lux) fluorescent bulbs installed in a box with a diffusing screen. It is set up on a table or desk top at which one can sit comfortably for the treatment session. Patients are instructed not to look directly at the light, but to engage in activities such as reading or writing while sitting near the box.
Previous research indicates that bright light affects the levels of some brain chemicals such as serotonin which is implicated in some forms of depression. The therapy is frequently used for patients suffering from seasonal affective disorder, a type of depression related to seasons such as winter when the days are shorter and people are exposed to less natural light.
The researchers administered the standard Hamilton Scale for depression to all study participants. This is a questionnaire used to evaluate the severity of depression.
The patients given bright light therapy made improvements over the controls comparable to the use of antidepressant drugs. Those using bright light therapy also showed an increased evening level of the sleep-promoting hormone melatonin and a decrease in the stress hormone cortisol.
Side effects during light therapy may include nausea, headaches, irritability and eye strain. Patients with certain eye disorders such as glaucoma or diabetic retinopathy are advised against using bright light therapy as a treatment.
Although home therapy is not recommended by many psychologists, light boxes can be purchased without a prescription for approximately $360-$500. Insurance reimbursement for the cost of the apparatus is not consistent. But if the policy covers psychiatric care or psychotherapy, it may also reimburse for clinical sessions involving light therapy.
Dr. Lieverse also warns that while light therapy is a low-cost, low-risk treatment for depressed patients who cannot tolerate antidepressants, clinical depression is a serious disorder and people with symptoms should not self-treat.
Lieveerse R, et al "Bright light treatment in elderly patients with nonseasonal major depressive disorder. A randomized placebo-controlled trial" Arch Gen Psych 2011; 68: 61-70.