Light therapy for better mood and insulin sensitivity in patients with major depression and type 2 diabetes: a randomised, double-blind, parallel-arm trial.
Study Goal
The researchers aimed to evaluate whether light therapy improves mood and insulin sensitivity in patients with type 2 diabetes and a major depressive episode.
Results Summary
The study protocol describes a randomized, double-blind trial to assess the effects of light therapy on depressive symptoms and insulin sensitivity, but results are not yet provided in the abstract.
Population
98 participants with type 2 diabetes and a major depressive episode (DSM-IV criteria).
Effective Dosage
Bright white-yellowish light or dim green light for half an hour every morning.
Duration
4 weeks of light therapy, with follow-up at 4 weeks post-intervention.
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
light therapy | decrease | depression | - | - | has been shown to be an effective antidepressant | #1 |
light therapy | neutral | the biological clock | - | - | 'resets' | #2 |
light therapy | increase | mood | patients with a major depressive episode and type 2 diabetes | - | improves | #3 |
light therapy | increase | insulin sensitivity | patients with a major depressive episode and type 2 diabetes | - | improves | #4 |
light therapy | decrease | depressive symptoms | participants with type 2 diabetes and a major depressive episode | - | improves | #5 |
light therapy | increase | insulin sensitivity | participants with type 2 diabetes and a major depressive episode | - | improves | #6 |
light therapy | neutral | treatment strategies | type 2 diabetes patients with a major depressive episode | - | may be a valuable patient friendly addition | #7 |
BACKGROUND: Major depression and type 2 diabetes often co-occur. Novel treatment strategies for depression in type 2 diabetes patients are warranted, as depression in type 2 diabetes patients is associated with poor prognosis and treatment results. Major depression and concurrent sleep disorders have been related to disturbances of the biological clock. The biological clock is also involved in regulation of glucose metabolism by modulating peripheral insulin sensitivity. Light therapy has been shown to be an effective antidepressant that 'resets' the biological clock. We here describe the protocol of a study that evaluates the hypothesis that light therapy improves mood as well as insulin sensitivity in patients with a major depressive episode and type 2 diabetes. METHODS/DESIGN: This study is a randomised, double-blind, parallel-arm trial in 98 participants with type 2 diabetes and a major depressive episode, according to DSM-IV criteria. We will assess whether light therapy improves depressive symptoms and insulin sensitivity, our primary outcome measures, and additionally investigate whether these effects are mediated by restoration of the circadian rhythmicity, as measured by sleep and hypothalamic-pituitary-adrenal axis activity. Participants will be randomly allocated to a bright white-yellowish light condition or dim green light condition. Participants will undergo light therapy for half an hour every morning for 4 weeks at home. At several time points, namely before the start of light therapy, during light therapy, after completion of 4 weeks of light therapy and after 4 weeks follow-up, several psychometrical, psychophysiological and glucometabolic measures will be performed. DISCUSSION: If light therapy effectively improves mood and insulin sensitivity in type 2 diabetes patients with a major depressive episode, light therapy may be a valuable patient friendly addition to the currently available treatment strategies. Additionally, if our data support the role of restoration of circadian rhythmicity, such an observation may guide further development of chronobiological treatment strategies in this patient population. TRIAL REGISTRATION: The Netherlands Trial Register (NTR) NTR4942 . Registered 13 January 2015.