None listed
Conditions
Brief summary
By the year 2030, depression is projected to the leading cause of disease burden worldwide. Although 1 in 10 Australians are currently taking an antidepressant medication, as many as 45% of patients will not respond to the beneficial effects of antidepressants. Depression is commonly associated with disrupted sleep and circadian ('body clock') rhythms, which rely on light from the environment. Previous research has found that there are individual differences in the sensitivity towards light, especially in patients taking Selective Serotonin Reuptake Inhibitors (SSRIs; the most common antidepressant medication). The increase in the effect of light from antidepressant medication on patients with depression may depend on the individual’s light exposure patterns. Individuals who tend to expose themselves to irregular light patterns especially at night, report poorer responses to SSRI treatment and increased depression during SSRI treatment compared to those that tend to seek bright light during the morning. Therefore, reducing evening home lighting and encouraging increased daylight exposure may enhance antidepressant efficacy. We aimed to investigate the ability of a circadian-informed light intervention to increase the beneficial effects of light and reduce the adverse effects of light on depressive symptoms and insomnia symptoms for individuals taking an SSRI.
Interventions
Participants allocated to the intervention group replaced their usual home lighting with pre-configured low-intensity warm smart LED bulbs (6.00 lux, 2452 K), used in place of their regular lighting in main living areas after sunset and before bedtime, for a period of four weeks. They were also asked to seek bright outdoor light during the day and reduce evening screen use before bed. This design aimed to reduce the disruptive effects of modern lighting environments (e.g., dim light during the d
Participants allocated to the intervention group replaced their usual home lighting with pre-configured low-intensity warm smart LED bulbs (6.00 lux, 2452 K), used in place of their regular lighting in main living areas after sunset and before bedtime, for a period of four weeks. They were also asked to seek bright outdoor light during the day and reduce evening screen use before bed. This design aimed to reduce the disruptive effects of modern lighting environments (e.g., dim light during the day and bright light in the evening) on the circadian system (known as the 'body clock') and subsequent mood. Participants received the pre-configured smart lighting equipment and a printed psychoeducation handout outlining the intervention instructions during an in-person visit at the laboratory, The intervention was then self-administered by participants in their own homes each evening over the four week period. Adherence to the intervention was assessed objectively using a wearable light monitoring device.
Sponsors
Monash University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
- A Beck Depression Inventory-II (BDI-II) score of 20 or more, indicating at least moderate depressive symptom severity. - Regular use of a SSRI for a minimum of 8 weeks prior to enrolment.
Exclusion criteria
- Major medical conditions - Current use of medications other than their antidepressant which may affect sleep or circadian rhythms - Recent shit-work or travel across time-zones - A history of psychosis or a family history of bipolar disorder - Current substance use disorder. - High risk of suicide
Outcome results
None listed