The treatment response (≥50% MADRS improvement) rate was highest in the combination treatment group (75.9%) with response rates to light monotherapy, placebo, and fluoxetine monotherapy of 50%, 33.3%, and 29%, respectively. There was a significant response effect for the combination vs placebo treatment group (P=.005). Similarly, there was a higher remission rate in the combination treatment group (58.6%) than in the placebo, light monotherapy, or fluoxetine treatment groups (30%, 43.8%, and 19.4%, respectively) with a significant effect for the combination vs placebo treatment group (P=.02).
Combination therapy was superior to placebo in treatment response (≥50% reduction in the MADRS score) and remission (MADRS ≤10) with numbers needed to treat of 2.4 (95% CI, 1.6-5.8) and 3.5 (95% CI, 2.0-29.9), respectively.
By the end of the 8-week study period, 16 of 122 patients had dropped out; 2 reported lack of efficacy, 5 reported adverse effects, and the remainder cited administrative reasons, were lost to follow-up, or withdrew consent.
What’s New?
New evidence on a not-so-new treatment
We now have evidence that bright light therapy, either alone or in combination with fluoxetine, is efficacious in increasing the remission rate of nonseasonal MDD.
Caveats
Choice of SSRI, geography, and trial duration may have affected results
A single SSRI (fluoxetine) was used in this study; other more potent SSRIs might work better. This study was conducted in southern Canada, and light therapy may not demonstrate as large a benefit in regions located farther south. The study excluded pregnant and breastfeeding women.
The trial duration was relatively short, and the investigators did not attain their pre-planned sample size for the study, which limited the power to detect clinically significant seasonal treatment effects and differences between the fluoxetine and placebo groups, regardless of whether they received active phototherapy.
Also, it’s worth noting that there were trends for some adverse events (nausea, heartburn, weight gain, agitation, sexual dysfunction, and skin rash) to occur less frequently in the combination group than in the fluoxetine monotherapy group. Possible explanations are that the study had inadequate power, that the sham treatment did not adequately blind patients, or that light therapy can ameliorate some of the adverse effects of fluoxetine.
Challenges to Implementation
Commercial insurance doesn’t usually cover light therapy
Bright light therapy is fairly safe, and some evidence exists supporting its use in the treatment of nonseasonal MDD; however, the data for its use in this area are limited.11 Since only a few studies have tested light therapy for nonseasonal MDD, significant uncertainty remains about patient selection, as well as optimal dose, timing, and duration of light therapy in the management of nonseasonal MDD.12 Although the risks associated with bright light therapy are minimal, the therapy can lead to mania or hypomania,3 so clinicians need to monitor for such effects when initiating therapy.
Lastly, commercial insurance does not usually cover light therapy. The average price of the bright light devices, which can be found in medical supply stores and online outlets, ranges between $118 and $237.4,12 However, such devices are reusable, making the amortized cost almost negligible.13
ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.
