In 2011, a plethora of research was convincingly showing that bright light should help alleviate depression in adults. A few studies also gathered promising results about the elderly. However, the real proof – a double-blind, placebo-controlled, random trial – was missing.
And it was this study that changed the situation and proved bright light therapy effective in depressed people above 60 years of age. Its results are positive and less trivial than it might seem given the body of research devoted to adults.
Elderly people differ from middle-aged adults, but light therapy works for them as well.
What is different in the elderly? Photoreception declines in aging. Together with the decreased input from the retina, changes in the melatonin daily cycle, and reduced activity of the suprachiasmatic nucleus, our “inner clock” weakens. Unsurprisingly, sleep and depression problems are common in elderly people. It was not known whether the differences related to higher age may make the benefits of light therapy stronger or weaker.
Measures of depression and biological values were taken before and after the three weeks of bright light therapy and again after another three weeks to check whether the effects are stable:
- Immediately after the treatment, those receiving bright light for three weeks improved 43% of their symptoms, compared to 37% in the placebo group.
- After three additional weeks, those receiving bright light improved 54% of their initial complaints, while those receiving placebo only improved 33%.
- 58% patients were no longer considered depressed three weeks after the light treatment compared to 34% in the placebo group.
- Sleep efficiency was improved by 2% by bright light and the steepness of rise of melatonin production in the evening increased by 87%
- The level of stress hormone cortisol was 37% lower in the treatment group compared to the placebo group when measured in urine and 33% when measured in saliva.
Conclusion: light therapy is effective in the elderly
These results support inclusion of chronotherapeutic strategies in the treatment options for nonseasonal MDD in elderly patients. Bright light treatment may provide a viable alternative for patients who refuse, resist, or do not tolerate antidepressant treatment.Lieverse et al. (2011). Bright Light Treatment in Elderly Patients With Nonseasonal Major Depressive Disorder: A Randomized Placebo-Controlled Trial. Arch Gen Psychiatry. 2011;68(1):61-70.
More recent data is consistent with these findings. In 2018, two independent meta-analytical studies confirmed that bright light therapy is an effective tool to fight geriatric depression.
For those who would like to try it out, I would recommend the guidelines for treatment of depression. And since it was Philips devices used in this study, I would stuck to the same brand and buy a Phillips lamp (on a side note: they sell light alarms and dawn simulators together with therapy lamps, so make sure you opt for a white or blue therapy device rather than those reddish lamps made to wake you up).
Technical details: Bright pale blue or dim red light treatment therapy at home using 2 light boxes (Phillips Bright Light Energy HF 3304; Koninklijke Philips Electronics NV, Eindhoven, the Netherlands). Concealed within the light boxes, a single-layer filter was wrapped around the fluorescent tubes: a mist-blue filter (Model 061; Lee Filters, Andover, England) with high-throughput pale blue (7500 lux) for the active condition and a blood-red filter (Model 789; Lee Filters) with low-throughput red (50 lux) for the placebo condition.